From fd0a38f9c37d539f5603f887cdb637a4e6e6944d Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Tue, 23 Aug 2022 16:53:26 +0100 Subject: scripts/bpf: Set version attribute for bpf-helpers(7) man page The bpf-helpers(7) manual page shipped in the man-pages project is generated from the documentation contained in the BPF UAPI header, in the Linux repository, parsed by script/bpf_doc.py and then fed to rst2man. After a recent update of that page [0], Alejandro reported that the linter used to validate the man pages complains about the generated document [1]. The header for the page is supposed to contain some attributes that we do not set correctly with the script. This commit updates the "project and version" field. We discussed the format of those fields in [1] and [2]. Before: $ ./scripts/bpf_doc.py helpers | rst2man | grep '\.TH' .TH BPF-HELPERS 7 "" "" "" After: $ ./scripts/bpf_doc.py helpers | rst2man | grep '\.TH' .TH BPF-HELPERS 7 "" "Linux v5.19-14022-g30d2a4d74e11" "" We get the version from "git describe", but if unavailable, we fall back on "make kernelversion". If none works, for example because neither git nore make are installed, we just set the field to "Linux" and keep generating the page. [0] https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/commit/man7/bpf-helpers.7?id=19c7f78393f2b038e76099f87335ddf43a87f039 [1] https://lore.kernel.org/all/20220823084719.13613-1-quentin@isovalent.com/t/#m58a418a318642c6428e14ce9bb84eba5183b06e8 [2] https://lore.kernel.org/all/20220721110821.8240-1-alx.manpages@gmail.com/t/#m8e689a822e03f6e2530a0d6de9d128401916c5de Reported-by: Alejandro Colomar Signed-off-by: Quentin Monnet Signed-off-by: Daniel Borkmann Reviewed-by: Alejandro Colomar Link: https://lore.kernel.org/bpf/20220823155327.98888-1-quentin@isovalent.com --- scripts/bpf_doc.py | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/bpf_doc.py b/scripts/bpf_doc.py index dfb260de17a8..061ad1dc3212 100755 --- a/scripts/bpf_doc.py +++ b/scripts/bpf_doc.py @@ -10,6 +10,8 @@ from __future__ import print_function import argparse import re import sys, os +import subprocess + class NoHelperFound(BaseException): pass @@ -357,6 +359,20 @@ class PrinterRST(Printer): print('') + def get_kernel_version(self): + try: + version = subprocess.run(['git', 'describe'], cwd=linuxRoot, + capture_output=True, check=True) + version = version.stdout.decode().rstrip() + except: + try: + version = subprocess.run(['make', 'kernelversion'], cwd=linuxRoot, + capture_output=True, check=True) + version = version.stdout.decode().rstrip() + except: + return 'Linux' + return 'Linux {version}'.format(version=version) + class PrinterHelpersRST(PrinterRST): """ A printer for dumping collected information about helpers as a ReStructured @@ -378,6 +394,7 @@ list of eBPF helper functions ------------------------------------------------------------------------------- :Manual section: 7 +:Version: {version} DESCRIPTION =========== @@ -410,8 +427,10 @@ kernel at the top). HELPERS ======= ''' + kernelVersion = self.get_kernel_version() + PrinterRST.print_license(self) - print(header) + print(header.format(version=kernelVersion)) def print_footer(self): footer = ''' -- cgit v1.2.3-59-g8ed1b From 92ec1cc3784a2a8a7a62596dcec4f2224b85dcf4 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Tue, 23 Aug 2022 16:53:27 +0100 Subject: scripts/bpf: Set date attribute for bpf-helpers(7) man page The bpf-helpers(7) manual page shipped in the man-pages project is generated from the documentation contained in the BPF UAPI header, in the Linux repository, parsed by script/bpf_doc.py and then fed to rst2man. The man page should contain the date of last modification of the documentation. This commit adds the relevant date when generating the page. Before: $ ./scripts/bpf_doc.py helpers | rst2man | grep '\.TH' .TH BPF-HELPERS 7 "" "Linux v5.19-14022-g30d2a4d74e11" "" After: $ ./scripts/bpf_doc.py helpers | rst2man | grep '\.TH' .TH BPF-HELPERS 7 "2022-08-15" "Linux v5.19-14022-g30d2a4d74e11" "" We get the version by using "git log" to look for the commit date of the latest change to the section of the BPF header containing the documentation. If the command fails, we just skip the date field. and keep generating the page. Reported-by: Alejandro Colomar Signed-off-by: Quentin Monnet Signed-off-by: Daniel Borkmann Reviewed-by: Alejandro Colomar Link: https://lore.kernel.org/bpf/20220823155327.98888-2-quentin@isovalent.com --- scripts/bpf_doc.py | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/bpf_doc.py b/scripts/bpf_doc.py index 061ad1dc3212..f4f3e7ec6d44 100755 --- a/scripts/bpf_doc.py +++ b/scripts/bpf_doc.py @@ -12,6 +12,7 @@ import re import sys, os import subprocess +helpersDocStart = 'Start of BPF helper function descriptions:' class NoHelperFound(BaseException): pass @@ -235,7 +236,7 @@ class HeaderParser(object): self.enum_syscalls = re.findall('(BPF\w+)+', bpf_cmd_str) def parse_desc_helpers(self): - self.seek_to('* Start of BPF helper function descriptions:', + self.seek_to(helpersDocStart, 'Could not find start of eBPF helper descriptions list') while True: try: @@ -373,6 +374,17 @@ class PrinterRST(Printer): return 'Linux' return 'Linux {version}'.format(version=version) + def get_last_doc_update(self, delimiter): + try: + cmd = ['git', 'log', '-1', '--pretty=format:%cs', '--no-patch', + '-L', + '/{}/,/\*\//:include/uapi/linux/bpf.h'.format(delimiter)] + date = subprocess.run(cmd, cwd=linuxRoot, + capture_output=True, check=True) + return date.stdout.decode().rstrip() + except: + return '' + class PrinterHelpersRST(PrinterRST): """ A printer for dumping collected information about helpers as a ReStructured @@ -395,6 +407,7 @@ list of eBPF helper functions :Manual section: 7 :Version: {version} +{date_field}{date} DESCRIPTION =========== @@ -428,9 +441,12 @@ HELPERS ======= ''' kernelVersion = self.get_kernel_version() + lastUpdate = self.get_last_doc_update(helpersDocStart) PrinterRST.print_license(self) - print(header.format(version=kernelVersion)) + print(header.format(version=kernelVersion, + date_field = ':Date: ' if lastUpdate else '', + date=lastUpdate)) def print_footer(self): footer = ''' -- cgit v1.2.3-59-g8ed1b From 0a0d55ef3e61d9f14e803cacb644fcc890f16774 Mon Sep 17 00:00:00 2001 From: Eyal Birger Date: Wed, 24 Aug 2022 21:10:43 +0300 Subject: bpf/scripts: Assert helper enum value is aligned with comment order The helper value is ABI as defined by enum bpf_func_id. As bpf_helper_defs.h is used for the userpace part, it must be consistent with this enum. Before this change the comments order was used by the bpf_doc script in order to set the helper values defined in the helpers file. When adding new helpers it is very puzzling when the userspace application breaks in weird places if the comment is inserted instead of appended - because the generated helper ABI is incorrect and shifted. This commit sets the helper value to the enum value. In addition it is currently the practice to have the comments appended and kept in the same order as the enum. As such, add an assertion validating the comment order is consistent with enum value. In case a different comments ordering is desired, this assertion can be lifted. Signed-off-by: Eyal Birger Signed-off-by: Andrii Nakryiko Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20220824181043.1601429-1-eyal.birger@gmail.com --- scripts/bpf_doc.py | 39 ++++++++++++++++++++++++++++++++++----- 1 file changed, 34 insertions(+), 5 deletions(-) (limited to 'scripts') diff --git a/scripts/bpf_doc.py b/scripts/bpf_doc.py index f4f3e7ec6d44..d5c389df6045 100755 --- a/scripts/bpf_doc.py +++ b/scripts/bpf_doc.py @@ -50,6 +50,10 @@ class Helper(APIElement): @desc: textual description of the helper function @ret: description of the return value of the helper function """ + def __init__(self, *args, **kwargs): + super().__init__(*args, **kwargs) + self.enum_val = None + def proto_break_down(self): """ Break down helper function protocol into smaller chunks: return type, @@ -92,6 +96,7 @@ class HeaderParser(object): self.commands = [] self.desc_unique_helpers = set() self.define_unique_helpers = [] + self.helper_enum_vals = {} self.desc_syscalls = [] self.enum_syscalls = [] @@ -248,30 +253,54 @@ class HeaderParser(object): break def parse_define_helpers(self): - # Parse the number of FN(...) in #define __BPF_FUNC_MAPPER to compare - # later with the number of unique function names present in description. + # Parse FN(...) in #define __BPF_FUNC_MAPPER to compare later with the + # number of unique function names present in description and use the + # correct enumeration value. # Note: seek_to(..) discards the first line below the target search text, # resulting in FN(unspec) being skipped and not added to self.define_unique_helpers. self.seek_to('#define __BPF_FUNC_MAPPER(FN)', 'Could not find start of eBPF helper definition list') - # Searches for either one or more FN(\w+) defines or a backslash for newline - p = re.compile('\s*(FN\(\w+\))+|\\\\') + # Searches for one FN(\w+) define or a backslash for newline + p = re.compile('\s*FN\((\w+)\)|\\\\') fn_defines_str = '' + i = 1 # 'unspec' is skipped as mentioned above while True: capture = p.match(self.line) if capture: fn_defines_str += self.line + self.helper_enum_vals[capture.expand(r'bpf_\1')] = i + i += 1 else: break self.line = self.reader.readline() # Find the number of occurences of FN(\w+) self.define_unique_helpers = re.findall('FN\(\w+\)', fn_defines_str) + def assign_helper_values(self): + seen_helpers = set() + for helper in self.helpers: + proto = helper.proto_break_down() + name = proto['name'] + try: + enum_val = self.helper_enum_vals[name] + except KeyError: + raise Exception("Helper %s is missing from enum bpf_func_id" % name) + + # Enforce current practice of having the descriptions ordered + # by enum value. + seen_helpers.add(name) + desc_val = len(seen_helpers) + if desc_val != enum_val: + raise Exception("Helper %s comment order (#%d) must be aligned with its position (#%d) in enum bpf_func_id" % (name, desc_val, enum_val)) + + helper.enum_val = enum_val + def run(self): self.parse_desc_syscall() self.parse_enum_syscall() self.parse_desc_helpers() self.parse_define_helpers() + self.assign_helper_values() self.reader.close() ############################################################################### @@ -796,7 +825,7 @@ class PrinterHelpers(Printer): comma = ', ' print(one_arg, end='') - print(') = (void *) %d;' % len(self.seen_helpers)) + print(') = (void *) %d;' % helper.enum_val) print('') ############################################################################### -- cgit v1.2.3-59-g8ed1b From 765f2bf04fdaced4e7d7e94cfc3f743048629f31 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Mon, 8 Aug 2022 10:59:28 +0200 Subject: scripts/decodecode: improve faulting line determination There are cases where the IP pointer in a Code: line in an oops doesn't point at the beginning of an instruction: Code: 0f bd c2 e9 a0 cd b5 e4 48 0f bd c2 e9 97 cd b5 e4 0f 1f 80 00 00 00 00 \ e9 8b cd b5 e4 0f 1f 00 66 0f a3 d0 e9 7f cd b5 e4 0f 1f <80> 00 00 00 \ 00 0f a3 d0 e9 70 cd b5 e4 48 0f a3 d0 e9 67 cd b5 e9 7f cd b5 e4 jmp 0xffffffffe4b5cda8 0f 1f 80 00 00 00 00 nopl 0x0(%rax) ^^ and the current way of determining the faulting instruction line doesn't work because disassembled instructions are counted from the IP byte to the end and when that thing points in the middle, the trailing bytes can be interpreted as different insns: Code starting with the faulting instruction =========================================== 0: 80 00 00 addb $0x0,(%rax) 3: 00 00 add %al,(%rax) whereas, this is part of 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 5: 0f a3 d0 bt %edx,%eax ... leading to: 1d: 0f 1f 00 nopl (%rax) 20: 66 0f a3 d0 bt %dx,%ax 24:* e9 7f cd b5 e4 jmp 0xffffffffe4b5cda8 <-- trapping instruction 29: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 30: 0f a3 d0 bt %edx,%eax which is the wrong faulting instruction. Change the way the faulting line number is determined by matching the opcode bytes from the beginning, leading to correct output: 1d: 0f 1f 00 nopl (%rax) 20: 66 0f a3 d0 bt %dx,%ax 24: e9 7f cd b5 e4 jmp 0xffffffffe4b5cda8 29:* 0f 1f 80 00 00 00 00 nopl 0x0(%rax) <-- trapping instruction 30: 0f a3 d0 bt %edx,%eax While at it, make decodecode use bash as the interpreter - that thing should be present on everything by now. It simplifies the code a lot too. Link: https://lkml.kernel.org/r/20220808085928.29840-1-bp@alien8.de Signed-off-by: Borislav Petkov Cc: Marc Zyngier Cc: Will Deacon Signed-off-by: Andrew Morton --- scripts/decodecode | 120 ++++++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 105 insertions(+), 15 deletions(-) (limited to 'scripts') diff --git a/scripts/decodecode b/scripts/decodecode index c711a196511c..b28fd2686561 100755 --- a/scripts/decodecode +++ b/scripts/decodecode @@ -1,4 +1,4 @@ -#!/bin/sh +#!/bin/bash # SPDX-License-Identifier: GPL-2.0 # Disassemble the Code: line in Linux oopses # usage: decodecode < oops.file @@ -8,6 +8,8 @@ # AFLAGS=--32 decodecode < 386.oops # PC=hex - the PC (program counter) the oops points to +faultlinenum=1 + cleanup() { rm -f $T $T.s $T.o $T.oo $T.aa $T.dis exit 1 @@ -102,28 +104,125 @@ disas() { grep -v "/tmp\|Disassembly\|\.text\|^$" > $t.dis 2>&1 } +# Match the maximum number of opcode bytes from @op_bytes contained within +# @opline +# +# Params: +# @op_bytes: The string of bytes from the Code: line +# @opline: The disassembled line coming from objdump +# +# Returns: +# The max number of opcode bytes from the beginning of @op_bytes which match +# the opcode bytes in the objdump line. +get_substr_opcode_bytes_num() +{ + local op_bytes=$1 + local opline=$2 + + local retval=0 + substr="" + + for opc in $op_bytes; + do + substr+="$opc" + + # return if opcode bytes do not match @opline anymore + if ! echo $opline | grep -q "$substr"; + then + break + fi + + # add trailing space + substr+=" " + retval=$((retval+1)) + done + + return $retval +} + +# Return the line number in objdump output to where the IP marker in the Code: +# line points to +# +# Params: +# @all_code: code in bytes without the marker +# @dis_file: disassembled file +# @ip_byte: The byte to which the IP points to +get_faultlinenum() +{ + local all_code="$1" + local dis_file="$2" + + # num bytes including IP byte + local num_bytes_ip=$(( $3 + 1 * $width )) + + # Add the two header lines (we're counting from 1). + local retval=3 + + # remove marker + all_code=$(echo $all_code | sed -e 's/[<>()]//g') + + while read line + do + get_substr_opcode_bytes_num "$all_code" "$line" + ate_opcodes=$? + + if ! (( $ate_opcodes )); then + continue + fi + + num_bytes_ip=$((num_bytes_ip - ($ate_opcodes * $width) )) + if (( $num_bytes_ip <= 0 )); then + break + fi + + # Delete matched opcode bytes from all_code. For that, compute + # how many chars those opcodes are represented by and include + # trailing space. + # + # a byte is 2 chars, ate_opcodes is also the number of trailing + # spaces + del_chars=$(( ($ate_opcodes * $width * 2) + $ate_opcodes )) + + all_code=$(echo $all_code | sed -e "s!^.\{$del_chars\}!!") + + let "retval+=1" + + done < $dis_file + + return $retval +} + marker=`expr index "$code" "\<"` if [ $marker -eq 0 ]; then marker=`expr index "$code" "\("` fi - touch $T.oo if [ $marker -ne 0 ]; then - # 2 opcode bytes and a single space - pc_sub=$(( $marker / 3 )) + # How many bytes to subtract from the program counter + # in order to get to the beginning virtual address of the + # Code: + pc_sub=$(( (($marker - 1) / (2 * $width + 1)) * $width )) echo All code >> $T.oo echo ======== >> $T.oo beforemark=`echo "$code"` echo -n " .$type 0x" > $T.s + echo $beforemark | sed -e 's/ /,0x/g; s/[<>()]//g' >> $T.s + disas $T $pc_sub + cat $T.dis >> $T.oo - rm -f $T.o $T.s $T.dis -# and fix code at-and-after marker + get_faultlinenum "$code" "$T.dis" $pc_sub + faultlinenum=$? + + # and fix code at-and-after marker code=`echo "$code" | cut -c$((${marker} + 1))-` + + rm -f $T.o $T.s $T.dis fi + echo Code starting with the faulting instruction > $T.aa echo =========================================== >> $T.aa code=`echo $code | sed -e 's/\r//;s/ [<(]/ /;s/[>)] / /;s/ /,0x/g; s/[>)]$//'` @@ -132,15 +231,6 @@ echo $code >> $T.s disas $T 0 cat $T.dis >> $T.aa -# (lines of whole $T.oo) - (lines of $T.aa, i.e. "Code starting") + 3, -# i.e. the title + the "===..=" line (sed is counting from 1, 0 address is -# special) -faultlinenum=$(( $(wc -l $T.oo | cut -d" " -f1) - \ - $(wc -l $T.aa | cut -d" " -f1) + 3)) - -faultline=`cat $T.dis | head -1 | cut -d":" -f2-` -faultline=`echo "$faultline" | sed -e 's/\[/\\\[/g; s/\]/\\\]/g'` - cat $T.oo | sed -e "${faultlinenum}s/^\([^:]*:\)\(.*\)/\1\*\2\t\t<-- trapping instruction/" echo cat $T.aa -- cgit v1.2.3-59-g8ed1b From defdaff15a84c68521c5f02b157fc8541e0356f3 Mon Sep 17 00:00:00 2001 From: Ira Weiny Date: Sat, 13 Aug 2022 15:00:34 -0700 Subject: checkpatch: add kmap and kmap_atomic to the deprecated list kmap() and kmap_atomic() are being deprecated in favor of kmap_local_page(). There are two main problems with kmap(): (1) It comes with an overhead as mapping space is restricted and protected by a global lock for synchronization and (2) it also requires global TLB invalidation when the kmap's pool wraps and it might block when the mapping space is fully utilized until a slot becomes available. kmap_local_page() is safe from any context and is therefore redundant with kmap_atomic() with the exception of any pagefault or preemption disable requirements. However, using kmap_atomic() for these side effects makes the code less clear. So any requirement for pagefault or preemption disable should be made explicitly. With kmap_local_page() the mappings are per thread, CPU local, can take page faults, and can be called from any context (including interrupts). It is faster than kmap() in kernels with HIGHMEM enabled. Furthermore, the tasks can be preempted and, when they are scheduled to run again, the kernel virtual addresses are restored. Link: https://lkml.kernel.org/r/20220813220034.806698-1-ira.weiny@intel.com Signed-off-by: Ira Weiny Suggested-by: Thomas Gleixner Suggested-by: Fabio M. De Francesco Reviewed-by: Chaitanya Kulkarni Cc: Joe Perches Signed-off-by: Andrew Morton --- scripts/checkpatch.pl | 2 ++ 1 file changed, 2 insertions(+) (limited to 'scripts') diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 79e759aac543..9ff219e0a9d5 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -807,6 +807,8 @@ our %deprecated_apis = ( "rcu_barrier_sched" => "rcu_barrier", "get_state_synchronize_sched" => "get_state_synchronize_rcu", "cond_synchronize_sched" => "cond_synchronize_rcu", + "kmap" => "kmap_local_page", + "kmap_atomic" => "kmap_local_page", ); #Create a search pattern for all these strings to speed up a loop below -- cgit v1.2.3-59-g8ed1b From 8ea0114eda0c1c85f8f01922ac8fc1e489a61129 Mon Sep 17 00:00:00 2001 From: Mickaël Salaün Date: Fri, 2 Sep 2022 13:19:23 +0200 Subject: checkpatch: handle FILE pointer type MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When using a "FILE *" type, checkpatch considers this an error: ERROR: need consistent spacing around '*' (ctx:WxV) #32: FILE: f.c:8: +static void a(FILE *const b) ^ Fix this by explicitly defining "FILE" as a common type. This is useful for user space patches. With this patch, we now get: <_>WS( ) <_>IDENT(static) <_>WS( ) <_>DECLARE(void ) <_>FUNC(a) PAREN('(') <_>DECLARE(FILE *const ) <_>IDENT(b) <_>PAREN(')') -> V <_>WS( ) 32 > . static void a(FILE *const b) 32 > EEVVVVVVVTTTTTVNTTTTTTTTTTTTVVV 32 > ______________________________ Link: https://lkml.kernel.org/r/20220902111923.1488671-1-mic@digikod.net Link: https://lore.kernel.org/r/20220902111923.1488671-1-mic@digikod.net Signed-off-by: Mickaël Salaün Acked-by: Joe Perches Cc: Andy Whitcroft Cc: Dwaipayan Ray Cc: Lukas Bulwahn Signed-off-by: Andrew Morton --- scripts/checkpatch.pl | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 9ff219e0a9d5..18effbe1fe90 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -576,10 +576,14 @@ our $typeKernelTypedefs = qr{(?x: (?:__)?(?:u|s|be|le)(?:8|16|32|64)| atomic_t )}; +our $typeStdioTypedefs = qr{(?x: + FILE +)}; our $typeTypedefs = qr{(?x: $typeC99Typedefs\b| $typeOtherOSTypedefs\b| - $typeKernelTypedefs\b + $typeKernelTypedefs\b| + $typeStdioTypedefs\b )}; our $zero_initializer = qr{(?:(?:0[xX])?0+$Int_type?|NULL|false)\b}; -- cgit v1.2.3-59-g8ed1b From c969bb8dbaf2f3628927eae73e7c579a74cf1b6e Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Tue, 20 Sep 2022 19:12:52 +0200 Subject: selinux: use "grep -E" instead of "egrep" The latest version of grep claims that egrep is now obsolete so the build now contains warnings that look like: egrep: warning: egrep is obsolescent; using grep -E fix this by using "grep -E" instead. Cc: Paul Moore Cc: Stephen Smalley Cc: Eric Paris Cc: selinux@vger.kernel.org Signed-off-by: Greg Kroah-Hartman [PM: tweak to remove vdso reference, cleanup subj line] Signed-off-by: Paul Moore --- scripts/selinux/install_policy.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/selinux/install_policy.sh b/scripts/selinux/install_policy.sh index 2dccf141241d..20af56ce245c 100755 --- a/scripts/selinux/install_policy.sh +++ b/scripts/selinux/install_policy.sh @@ -78,7 +78,7 @@ cd /etc/selinux/dummy/contexts/files $SF -F file_contexts / mounts=`cat /proc/$$/mounts | \ - egrep "ext[234]|jfs|xfs|reiserfs|jffs2|gfs2|btrfs|f2fs|ocfs2" | \ + grep -E "ext[234]|jfs|xfs|reiserfs|jffs2|gfs2|btrfs|f2fs|ocfs2" | \ awk '{ print $2 '}` $SF -F file_contexts $mounts -- cgit v1.2.3-59-g8ed1b From 2fe2fb4ce60be9005d7bfdd5665be03b8efb5b13 Mon Sep 17 00:00:00 2001 From: Paul Moore Date: Tue, 20 Sep 2022 14:11:11 -0400 Subject: selinux: remove runtime disable message in the install_policy.sh script We are in the process of deprecating the runtime disable mechanism, let's not reference it in the scripts. Signed-off-by: Paul Moore --- scripts/selinux/install_policy.sh | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/selinux/install_policy.sh b/scripts/selinux/install_policy.sh index 20af56ce245c..24086793b0d8 100755 --- a/scripts/selinux/install_policy.sh +++ b/scripts/selinux/install_policy.sh @@ -31,8 +31,7 @@ fi if selinuxenabled; then echo "SELinux is already enabled" echo "This prevents safely relabeling all files." - echo "Boot with selinux=0 on the kernel command-line or" - echo "SELINUX=disabled in /etc/selinux/config." + echo "Boot with selinux=0 on the kernel command-line." exit 1 fi -- cgit v1.2.3-59-g8ed1b From 237fe72749425f2cd3132bf54fa6b98807c27938 Mon Sep 17 00:00:00 2001 From: yangxingwu Date: Tue, 13 Sep 2022 04:07:53 +0000 Subject: scripts/clang-tools: remove unused module Remove unused imported 'os' module. Signed-off-by: yangxingwu Reviewed-by: Nathan Chancellor Signed-off-by: Masahiro Yamada --- scripts/clang-tools/run-clang-tools.py | 1 - 1 file changed, 1 deletion(-) (limited to 'scripts') diff --git a/scripts/clang-tools/run-clang-tools.py b/scripts/clang-tools/run-clang-tools.py index 1337cedca096..bb78c9bde55c 100755 --- a/scripts/clang-tools/run-clang-tools.py +++ b/scripts/clang-tools/run-clang-tools.py @@ -12,7 +12,6 @@ compile_commands.json. import argparse import json import multiprocessing -import os import subprocess import sys -- cgit v1.2.3-59-g8ed1b From 03764b30a4f0185a97515d616e60e2e00c558583 Mon Sep 17 00:00:00 2001 From: Zeng Heng Date: Mon, 12 Sep 2022 17:48:38 +0800 Subject: Kconfig: remove unused function 'menu_get_root_menu' There is nowhere calling `menu_get_root_menu` function, so remove it. Signed-off-by: Zeng Heng Signed-off-by: Masahiro Yamada --- scripts/kconfig/lkc.h | 1 - scripts/kconfig/menu.c | 5 ----- 2 files changed, 6 deletions(-) (limited to 'scripts') diff --git a/scripts/kconfig/lkc.h b/scripts/kconfig/lkc.h index fa8c010aa683..c396aa104090 100644 --- a/scripts/kconfig/lkc.h +++ b/scripts/kconfig/lkc.h @@ -98,7 +98,6 @@ bool menu_is_empty(struct menu *menu); bool menu_is_visible(struct menu *menu); bool menu_has_prompt(struct menu *menu); const char *menu_get_prompt(struct menu *menu); -struct menu *menu_get_root_menu(struct menu *menu); struct menu *menu_get_parent_menu(struct menu *menu); bool menu_has_help(struct menu *menu); const char *menu_get_help(struct menu *menu); diff --git a/scripts/kconfig/menu.c b/scripts/kconfig/menu.c index 3d6f7cba8846..62b6313f51c8 100644 --- a/scripts/kconfig/menu.c +++ b/scripts/kconfig/menu.c @@ -661,11 +661,6 @@ const char *menu_get_prompt(struct menu *menu) return NULL; } -struct menu *menu_get_root_menu(struct menu *menu) -{ - return &rootmenu; -} - struct menu *menu_get_parent_menu(struct menu *menu) { enum prop_type type; -- cgit v1.2.3-59-g8ed1b From 61f2b7c7497ba96cdde5bbaeb9e07f4c48f41f97 Mon Sep 17 00:00:00 2001 From: Nick Desaulniers Date: Mon, 19 Sep 2022 10:30:30 -0700 Subject: Makefile.debug: set -g unconditional on CONFIG_DEBUG_INFO_SPLIT Dmitrii, Fangrui, and Mashahiro note: Before GCC 11 and Clang 12 -gsplit-dwarf implicitly uses -g2. Fix CONFIG_DEBUG_INFO_SPLIT for gcc-11+ & clang-12+ which now need -g specified in order for -gsplit-dwarf to work at all. -gsplit-dwarf has been mutually exclusive with -g since support for CONFIG_DEBUG_INFO_SPLIT was introduced in commit 866ced950bcd ("kbuild: Support split debug info v4") I don't think it ever needed to be. Link: https://lore.kernel.org/lkml/20220815013317.26121-1-dmitrii.bundin.a@gmail.com/ Link: https://lore.kernel.org/lkml/CAK7LNARPAmsJD5XKAw7m_X2g7Fi-CAAsWDQiP7+ANBjkg7R7ng@mail.gmail.com/ Link: https://reviews.llvm.org/D80391 Cc: Andi Kleen Reported-by: Dmitrii Bundin Reported-by: Fangrui Song Reported-by: Masahiro Yamada Suggested-by: Dmitrii Bundin Reviewed-by: Nathan Chancellor Signed-off-by: Nick Desaulniers Signed-off-by: Masahiro Yamada --- scripts/Makefile.debug | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'scripts') diff --git a/scripts/Makefile.debug b/scripts/Makefile.debug index 9f39b0130551..26d6a9d97a20 100644 --- a/scripts/Makefile.debug +++ b/scripts/Makefile.debug @@ -1,9 +1,7 @@ -DEBUG_CFLAGS := +DEBUG_CFLAGS := -g ifdef CONFIG_DEBUG_INFO_SPLIT DEBUG_CFLAGS += -gsplit-dwarf -else -DEBUG_CFLAGS += -g endif ifndef CONFIG_AS_IS_LLVM -- cgit v1.2.3-59-g8ed1b From 32ef9e5054ec0321b9336058c58ec749e9c6b0fe Mon Sep 17 00:00:00 2001 From: Nick Desaulniers Date: Mon, 19 Sep 2022 10:45:47 -0700 Subject: Makefile.debug: re-enable debug info for .S files Alexey reported that the fraction of unknown filename instances in kallsyms grew from ~0.3% to ~10% recently; Bill and Greg tracked it down to assembler defined symbols, which regressed as a result of: commit b8a9092330da ("Kbuild: do not emit debug info for assembly with LLVM_IAS=1") In that commit, I allude to restoring debug info for assembler defined symbols in a follow up patch, but it seems I forgot to do so in commit a66049e2cf0e ("Kbuild: make DWARF version a choice") Link: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=31bf18645d98b4d3d7357353be840e320649a67d Fixes: b8a9092330da ("Kbuild: do not emit debug info for assembly with LLVM_IAS=1") Reported-by: Alexey Alexandrov Reported-by: Bill Wendling Reported-by: Greg Thelen Reviewed-by: Nathan Chancellor Suggested-by: Masahiro Yamada Signed-off-by: Nick Desaulniers Signed-off-by: Masahiro Yamada --- lib/Kconfig.debug | 4 +++- scripts/Makefile.debug | 21 +++++++++++---------- 2 files changed, 14 insertions(+), 11 deletions(-) (limited to 'scripts') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index bcbe60d6c80c..d3e5f36bb01e 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -264,8 +264,10 @@ config DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT config DEBUG_INFO_DWARF4 bool "Generate DWARF Version 4 debuginfo" select DEBUG_INFO + depends on !CC_IS_CLANG || (CC_IS_CLANG && (AS_IS_LLVM || (AS_IS_GNU && AS_VERSION >= 23502))) help - Generate DWARF v4 debug info. This requires gcc 4.5+ and gdb 7.0+. + Generate DWARF v4 debug info. This requires gcc 4.5+, binutils 2.35.2 + if using clang without clang's integrated assembler, and gdb 7.0+. If you have consumers of DWARF debug info that are not ready for newer revisions of DWARF, you may wish to choose this or have your diff --git a/scripts/Makefile.debug b/scripts/Makefile.debug index 26d6a9d97a20..8cf1cb22dd93 100644 --- a/scripts/Makefile.debug +++ b/scripts/Makefile.debug @@ -1,18 +1,19 @@ -DEBUG_CFLAGS := -g +DEBUG_CFLAGS := +debug-flags-y := -g ifdef CONFIG_DEBUG_INFO_SPLIT DEBUG_CFLAGS += -gsplit-dwarf endif -ifndef CONFIG_AS_IS_LLVM -KBUILD_AFLAGS += -Wa,-gdwarf-2 -endif - -ifndef CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT -dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4 -dwarf-version-$(CONFIG_DEBUG_INFO_DWARF5) := 5 -DEBUG_CFLAGS += -gdwarf-$(dwarf-version-y) +debug-flags-$(CONFIG_DEBUG_INFO_DWARF4) += -gdwarf-4 +debug-flags-$(CONFIG_DEBUG_INFO_DWARF5) += -gdwarf-5 +ifeq ($(CONFIG_CC_IS_CLANG)$(CONFIG_AS_IS_GNU),yy) +# Clang does not pass -g or -gdwarf-* option down to GAS. +# Add -Wa, prefix to explicitly specify the flags. +KBUILD_AFLAGS += $(addprefix -Wa$(comma), $(debug-flags-y)) endif +DEBUG_CFLAGS += $(debug-flags-y) +KBUILD_AFLAGS += $(debug-flags-y) ifdef CONFIG_DEBUG_INFO_REDUCED DEBUG_CFLAGS += -fno-var-tracking @@ -27,5 +28,5 @@ KBUILD_AFLAGS += -gz=zlib KBUILD_LDFLAGS += --compress-debug-sections=zlib endif -KBUILD_CFLAGS += $(DEBUG_CFLAGS) +KBUILD_CFLAGS += $(DEBUG_CFLAGS) export DEBUG_CFLAGS -- cgit v1.2.3-59-g8ed1b From d0f9562ee43a135b941715d9e5e607de88898aca Mon Sep 17 00:00:00 2001 From: Sami Tolvanen Date: Thu, 8 Sep 2022 14:54:44 -0700 Subject: scripts/kallsyms: Ignore __kcfi_typeid_ The compiler generates __kcfi_typeid_ symbols for annotating assembly functions with type information. These are constants that can be referenced in assembly code and are resolved by the linker. Ignore them in kallsyms. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Kees Cook Tested-by: Nathan Chancellor Acked-by: Peter Zijlstra (Intel) Tested-by: Peter Zijlstra (Intel) Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20220908215504.3686827-3-samitolvanen@google.com --- scripts/kallsyms.c | 1 + 1 file changed, 1 insertion(+) (limited to 'scripts') diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c index f18e6dfc68c5..ccdf0c897f31 100644 --- a/scripts/kallsyms.c +++ b/scripts/kallsyms.c @@ -119,6 +119,7 @@ static bool is_ignored_symbol(const char *name, char type) "__ThumbV7PILongThunk_", "__LA25Thunk_", /* mips lld */ "__microLA25Thunk_", + "__kcfi_typeid_", /* CFI type identifiers */ NULL }; -- cgit v1.2.3-59-g8ed1b From 89245600941e4e0f87d77f60ee269b5e61ef4e49 Mon Sep 17 00:00:00 2001 From: Sami Tolvanen Date: Thu, 8 Sep 2022 14:54:47 -0700 Subject: cfi: Switch to -fsanitize=kcfi Switch from Clang's original forward-edge control-flow integrity implementation to -fsanitize=kcfi, which is better suited for the kernel, as it doesn't require LTO, doesn't use a jump table that requires altering function references, and won't break cross-module function address equality. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Kees Cook Tested-by: Nathan Chancellor Acked-by: Peter Zijlstra (Intel) Tested-by: Peter Zijlstra (Intel) Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20220908215504.3686827-6-samitolvanen@google.com --- Makefile | 13 +--- arch/Kconfig | 8 ++- include/asm-generic/vmlinux.lds.h | 37 +++++----- include/linux/cfi.h | 29 ++++++-- include/linux/compiler-clang.h | 14 +--- include/linux/module.h | 6 +- kernel/cfi.c | 144 ++++++++++++++++++-------------------- kernel/module/main.c | 35 +-------- scripts/module.lds.S | 23 ++---- 9 files changed, 133 insertions(+), 176 deletions(-) (limited to 'scripts') diff --git a/Makefile b/Makefile index a4f71076cacb..43e08c9f95e9 100644 --- a/Makefile +++ b/Makefile @@ -921,18 +921,7 @@ export CC_FLAGS_LTO endif ifdef CONFIG_CFI_CLANG -CC_FLAGS_CFI := -fsanitize=cfi \ - -fsanitize-cfi-cross-dso \ - -fno-sanitize-cfi-canonical-jump-tables \ - -fno-sanitize-trap=cfi \ - -fno-sanitize-blacklist - -ifdef CONFIG_CFI_PERMISSIVE -CC_FLAGS_CFI += -fsanitize-recover=cfi -endif - -# If LTO flags are filtered out, we must also filter out CFI. -CC_FLAGS_LTO += $(CC_FLAGS_CFI) +CC_FLAGS_CFI := -fsanitize=kcfi KBUILD_CFLAGS += $(CC_FLAGS_CFI) export CC_FLAGS_CFI endif diff --git a/arch/Kconfig b/arch/Kconfig index 5fd875e18c99..1c1eca0c0019 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -738,11 +738,13 @@ config ARCH_SUPPORTS_CFI_CLANG An architecture should select this option if it can support Clang's Control-Flow Integrity (CFI) checking. +config ARCH_USES_CFI_TRAPS + bool + config CFI_CLANG bool "Use Clang's Control Flow Integrity (CFI)" - depends on LTO_CLANG && ARCH_SUPPORTS_CFI_CLANG - depends on CLANG_VERSION >= 140000 - select KALLSYMS + depends on ARCH_SUPPORTS_CFI_CLANG + depends on $(cc-option,-fsanitize=kcfi) help This option enables Clang’s forward-edge Control Flow Integrity (CFI) checking, where the compiler injects a runtime check to each diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 7515a465ec03..7501edfce11e 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -421,6 +421,22 @@ __end_ro_after_init = .; #endif +/* + * .kcfi_traps contains a list KCFI trap locations. + */ +#ifndef KCFI_TRAPS +#ifdef CONFIG_ARCH_USES_CFI_TRAPS +#define KCFI_TRAPS \ + __kcfi_traps : AT(ADDR(__kcfi_traps) - LOAD_OFFSET) { \ + __start___kcfi_traps = .; \ + KEEP(*(.kcfi_traps)) \ + __stop___kcfi_traps = .; \ + } +#else +#define KCFI_TRAPS +#endif +#endif + /* * Read only Data */ @@ -529,6 +545,8 @@ __stop___modver = .; \ } \ \ + KCFI_TRAPS \ + \ RO_EXCEPTION_TABLE \ NOTES \ BTF \ @@ -537,21 +555,6 @@ __end_rodata = .; -/* - * .text..L.cfi.jumptable.* contain Control-Flow Integrity (CFI) - * jump table entries. - */ -#ifdef CONFIG_CFI_CLANG -#define TEXT_CFI_JT \ - . = ALIGN(PMD_SIZE); \ - __cfi_jt_start = .; \ - *(.text..L.cfi.jumptable .text..L.cfi.jumptable.*) \ - . = ALIGN(PMD_SIZE); \ - __cfi_jt_end = .; -#else -#define TEXT_CFI_JT -#endif - /* * Non-instrumentable text section */ @@ -579,7 +582,6 @@ *(.text..refcount) \ *(.ref.text) \ *(.text.asan.* .text.tsan.*) \ - TEXT_CFI_JT \ MEM_KEEP(init.text*) \ MEM_KEEP(exit.text*) \ @@ -1008,8 +1010,7 @@ * keep any .init_array.* sections. * https://bugs.llvm.org/show_bug.cgi?id=46478 */ -#if defined(CONFIG_GCOV_KERNEL) || defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KCSAN) || \ - defined(CONFIG_CFI_CLANG) +#if defined(CONFIG_GCOV_KERNEL) || defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KCSAN) # ifdef CONFIG_CONSTRUCTORS # define SANITIZER_DISCARDS \ *(.eh_frame) diff --git a/include/linux/cfi.h b/include/linux/cfi.h index 2cdbc0fbd0ab..5e134f4ce8b7 100644 --- a/include/linux/cfi.h +++ b/include/linux/cfi.h @@ -2,17 +2,38 @@ /* * Clang Control Flow Integrity (CFI) support. * - * Copyright (C) 2021 Google LLC + * Copyright (C) 2022 Google LLC */ #ifndef _LINUX_CFI_H #define _LINUX_CFI_H +#include +#include + #ifdef CONFIG_CFI_CLANG -typedef void (*cfi_check_fn)(uint64_t id, void *ptr, void *diag); +enum bug_trap_type report_cfi_failure(struct pt_regs *regs, unsigned long addr, + unsigned long *target, u32 type); -/* Compiler-generated function in each module, and the kernel */ -extern void __cfi_check(uint64_t id, void *ptr, void *diag); +static inline enum bug_trap_type report_cfi_failure_noaddr(struct pt_regs *regs, + unsigned long addr) +{ + return report_cfi_failure(regs, addr, NULL, 0); +} +#ifdef CONFIG_ARCH_USES_CFI_TRAPS +bool is_cfi_trap(unsigned long addr); +#endif #endif /* CONFIG_CFI_CLANG */ +#ifdef CONFIG_MODULES +#ifdef CONFIG_ARCH_USES_CFI_TRAPS +void module_cfi_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, + struct module *mod); +#else +static inline void module_cfi_finalize(const Elf_Ehdr *hdr, + const Elf_Shdr *sechdrs, + struct module *mod) {} +#endif /* CONFIG_ARCH_USES_CFI_TRAPS */ +#endif /* CONFIG_MODULES */ + #endif /* _LINUX_CFI_H */ diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h index c84fec767445..42e55579d649 100644 --- a/include/linux/compiler-clang.h +++ b/include/linux/compiler-clang.h @@ -66,17 +66,9 @@ # define __noscs __attribute__((__no_sanitize__("shadow-call-stack"))) #endif -#define __nocfi __attribute__((__no_sanitize__("cfi"))) -#define __cficanonical __attribute__((__cfi_canonical_jump_table__)) - -#if defined(CONFIG_CFI_CLANG) -/* - * With CONFIG_CFI_CLANG, the compiler replaces function address - * references with the address of the function's CFI jump table - * entry. The function_nocfi macro always returns the address of the - * actual function instead. - */ -#define function_nocfi(x) __builtin_function_start(x) +#if __has_feature(kcfi) +/* Disable CFI checking inside a function. */ +#define __nocfi __attribute__((__no_sanitize__("kcfi"))) #endif /* diff --git a/include/linux/module.h b/include/linux/module.h index 8937b020ec04..ec61fb53979a 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -27,7 +27,6 @@ #include #include #include -#include #include #include @@ -387,8 +386,9 @@ struct module { const s32 *crcs; unsigned int num_syms; -#ifdef CONFIG_CFI_CLANG - cfi_check_fn cfi_check; +#ifdef CONFIG_ARCH_USES_CFI_TRAPS + s32 *kcfi_traps; + s32 *kcfi_traps_end; #endif /* Kernel parameters. */ diff --git a/kernel/cfi.c b/kernel/cfi.c index e8bc1b370edc..08caad776717 100644 --- a/kernel/cfi.c +++ b/kernel/cfi.c @@ -1,105 +1,101 @@ // SPDX-License-Identifier: GPL-2.0 /* - * Clang Control Flow Integrity (CFI) error and slowpath handling. + * Clang Control Flow Integrity (CFI) error handling. * - * Copyright (C) 2021 Google LLC + * Copyright (C) 2022 Google LLC */ -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -/* Compiler-defined handler names */ -#ifdef CONFIG_CFI_PERMISSIVE -#define cfi_failure_handler __ubsan_handle_cfi_check_fail -#else -#define cfi_failure_handler __ubsan_handle_cfi_check_fail_abort -#endif - -static inline void handle_cfi_failure(void *ptr) +#include + +enum bug_trap_type report_cfi_failure(struct pt_regs *regs, unsigned long addr, + unsigned long *target, u32 type) { - if (IS_ENABLED(CONFIG_CFI_PERMISSIVE)) - WARN_RATELIMIT(1, "CFI failure (target: %pS):\n", ptr); + if (target) + pr_err("CFI failure at %pS (target: %pS; expected type: 0x%08x)\n", + (void *)addr, (void *)*target, type); else - panic("CFI failure (target: %pS)\n", ptr); + pr_err("CFI failure at %pS (no target information)\n", + (void *)addr); + + if (IS_ENABLED(CONFIG_CFI_PERMISSIVE)) { + __warn(NULL, 0, (void *)addr, 0, regs, NULL); + return BUG_TRAP_TYPE_WARN; + } + + return BUG_TRAP_TYPE_BUG; } -#ifdef CONFIG_MODULES +#ifdef CONFIG_ARCH_USES_CFI_TRAPS +static inline unsigned long trap_address(s32 *p) +{ + return (unsigned long)((long)p + (long)*p); +} -static inline cfi_check_fn find_module_check_fn(unsigned long ptr) +static bool is_trap(unsigned long addr, s32 *start, s32 *end) { - cfi_check_fn fn = NULL; - struct module *mod; + s32 *p; - rcu_read_lock_sched_notrace(); - mod = __module_address(ptr); - if (mod) - fn = mod->cfi_check; - rcu_read_unlock_sched_notrace(); + for (p = start; p < end; ++p) { + if (trap_address(p) == addr) + return true; + } - return fn; + return false; } -static inline cfi_check_fn find_check_fn(unsigned long ptr) +#ifdef CONFIG_MODULES +/* Populates `kcfi_trap(_end)?` fields in `struct module`. */ +void module_cfi_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, + struct module *mod) { - cfi_check_fn fn = NULL; - unsigned long flags; - bool rcu_idle; - - if (is_kernel_text(ptr)) - return __cfi_check; - - /* - * Indirect call checks can happen when RCU is not watching. Both - * the shadow and __module_address use RCU, so we need to wake it - * up if necessary. - */ - rcu_idle = !rcu_is_watching(); - if (rcu_idle) { - local_irq_save(flags); - ct_irq_enter(); - } + char *secstrings; + unsigned int i; - fn = find_module_check_fn(ptr); + mod->kcfi_traps = NULL; + mod->kcfi_traps_end = NULL; - if (rcu_idle) { - ct_irq_exit(); - local_irq_restore(flags); - } + secstrings = (char *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; + + for (i = 1; i < hdr->e_shnum; i++) { + if (strcmp(secstrings + sechdrs[i].sh_name, "__kcfi_traps")) + continue; - return fn; + mod->kcfi_traps = (s32 *)sechdrs[i].sh_addr; + mod->kcfi_traps_end = (s32 *)(sechdrs[i].sh_addr + sechdrs[i].sh_size); + break; + } } -void __cfi_slowpath_diag(uint64_t id, void *ptr, void *diag) +static bool is_module_cfi_trap(unsigned long addr) { - cfi_check_fn fn = find_check_fn((unsigned long)ptr); + struct module *mod; + bool found = false; - if (likely(fn)) - fn(id, ptr, diag); - else /* Don't allow unchecked modules */ - handle_cfi_failure(ptr); -} -EXPORT_SYMBOL(__cfi_slowpath_diag); + rcu_read_lock_sched_notrace(); -#else /* !CONFIG_MODULES */ + mod = __module_address(addr); + if (mod) + found = is_trap(addr, mod->kcfi_traps, mod->kcfi_traps_end); -void __cfi_slowpath_diag(uint64_t id, void *ptr, void *diag) + rcu_read_unlock_sched_notrace(); + + return found; +} +#else /* CONFIG_MODULES */ +static inline bool is_module_cfi_trap(unsigned long addr) { - handle_cfi_failure(ptr); /* No modules */ + return false; } -EXPORT_SYMBOL(__cfi_slowpath_diag); - #endif /* CONFIG_MODULES */ -void cfi_failure_handler(void *data, void *ptr, void *vtable) +extern s32 __start___kcfi_traps[]; +extern s32 __stop___kcfi_traps[]; + +bool is_cfi_trap(unsigned long addr) { - handle_cfi_failure(ptr); + if (is_trap(addr, __start___kcfi_traps, __stop___kcfi_traps)) + return true; + + return is_module_cfi_trap(addr); } -EXPORT_SYMBOL(cfi_failure_handler); +#endif /* CONFIG_ARCH_USES_CFI_TRAPS */ diff --git a/kernel/module/main.c b/kernel/module/main.c index 0228f44b58e5..70c0b2c6fef8 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -53,6 +53,7 @@ #include #include #include +#include #include #include "internal.h" @@ -2597,8 +2598,9 @@ static int complete_formation(struct module *mod, struct load_info *info) if (err < 0) goto out; - /* This relies on module_mutex for list integrity. */ + /* These rely on module_mutex for list integrity. */ module_bug_finalize(info->hdr, info->sechdrs, mod); + module_cfi_finalize(info->hdr, info->sechdrs, mod); if (module_check_misalignment(mod)) goto out_misaligned; @@ -2660,8 +2662,6 @@ static int unknown_module_param_cb(char *param, char *val, const char *modname, return 0; } -static void cfi_init(struct module *mod); - /* * Allocate and load the module: note that size of section 0 is always * zero, and we rely on this for optional sections. @@ -2791,9 +2791,6 @@ static int load_module(struct load_info *info, const char __user *uargs, flush_module_icache(mod); - /* Setup CFI for the module. */ - cfi_init(mod); - /* Now copy in args */ mod->args = strndup_user(uargs, ~0UL >> 1); if (IS_ERR(mod->args)) { @@ -2955,32 +2952,6 @@ static inline int within(unsigned long addr, void *start, unsigned long size) return ((void *)addr >= start && (void *)addr < start + size); } -static void cfi_init(struct module *mod) -{ -#ifdef CONFIG_CFI_CLANG - initcall_t *init; -#ifdef CONFIG_MODULE_UNLOAD - exitcall_t *exit; -#endif - - rcu_read_lock_sched(); - mod->cfi_check = (cfi_check_fn) - find_kallsyms_symbol_value(mod, "__cfi_check"); - init = (initcall_t *) - find_kallsyms_symbol_value(mod, "__cfi_jt_init_module"); - /* Fix init/exit functions to point to the CFI jump table */ - if (init) - mod->init = *init; -#ifdef CONFIG_MODULE_UNLOAD - exit = (exitcall_t *) - find_kallsyms_symbol_value(mod, "__cfi_jt_cleanup_module"); - if (exit) - mod->exit = *exit; -#endif - rcu_read_unlock_sched(); -#endif -} - /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */ char *module_flags(struct module *mod, char *buf, bool show_state) { diff --git a/scripts/module.lds.S b/scripts/module.lds.S index 3a3aa2354ed8..da4bddd26171 100644 --- a/scripts/module.lds.S +++ b/scripts/module.lds.S @@ -3,20 +3,10 @@ * Archs are free to supply their own linker scripts. ld will * combine them automatically. */ -#ifdef CONFIG_CFI_CLANG -# include -# define ALIGN_CFI ALIGN(PAGE_SIZE) -# define SANITIZER_DISCARDS *(.eh_frame) -#else -# define ALIGN_CFI -# define SANITIZER_DISCARDS -#endif - SECTIONS { /DISCARD/ : { *(.discard) *(.discard.*) - SANITIZER_DISCARDS } __ksymtab 0 : { *(SORT(___ksymtab+*)) } @@ -33,6 +23,10 @@ SECTIONS { __patchable_function_entries : { *(__patchable_function_entries) } +#ifdef CONFIG_ARCH_USES_CFI_TRAPS + __kcfi_traps : { KEEP(*(.kcfi_traps)) } +#endif + #ifdef CONFIG_LTO_CLANG /* * With CONFIG_LTO_CLANG, LLD always enables -fdata-sections and @@ -53,15 +47,6 @@ SECTIONS { *(.rodata .rodata.[0-9a-zA-Z_]*) *(.rodata..L*) } - - /* - * With CONFIG_CFI_CLANG, we assume __cfi_check is at the beginning - * of the .text section, and is aligned to PAGE_SIZE. - */ - .text : ALIGN_CFI { - *(.text.__cfi_check) - *(.text .text.[0-9a-zA-Z_]* .text..L.cfi*) - } #endif } -- cgit v1.2.3-59-g8ed1b From d7c6ea024c08bbdb799768f51ffd9fdd6236d190 Mon Sep 17 00:00:00 2001 From: Dmitry Baryshkov Date: Thu, 15 Sep 2022 14:44:22 +0300 Subject: kbuild: take into account DT_SCHEMA_FILES changes while checking dtbs It is useful to be able to recheck dtbs files against a limited set of DT schema files. This can be accomplished by using differnt DT_SCHEMA_FILES argument values while rerunning make dtbs_check. However for some reason if_changed_rule doesn't pick up the rule_dtc changes (and doesn't retrigger the build). Fix this by changing if_changed_rule to if_changed_dep and squashing DTC and dt-validate into a single new command. Then if_changed_dep triggers on DT_SCHEMA_FILES changes and reruns the build/check. Signed-off-by: Dmitry Baryshkov Link: https://lore.kernel.org/r/20220915114422.79378-1-dmitry.baryshkov@linaro.org Signed-off-by: Rob Herring --- scripts/Makefile.lib | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) (limited to 'scripts') diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 3fb6a99e78c4..cec0560f6ac6 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -371,17 +371,15 @@ DT_CHECKER_FLAGS ?= $(if $(DT_SCHEMA_FILES),-l $(DT_SCHEMA_FILES),-m) DT_BINDING_DIR := Documentation/devicetree/bindings DT_TMP_SCHEMA := $(objtree)/$(DT_BINDING_DIR)/processed-schema.json -quiet_cmd_dtb_check = CHECK $@ - cmd_dtb_check = $(DT_CHECKER) $(DT_CHECKER_FLAGS) -u $(srctree)/$(DT_BINDING_DIR) -p $(DT_TMP_SCHEMA) $@ || true +quiet_cmd_dtb = DTC_CHK $@ + cmd_dtb = $(cmd_dtc) ; $(DT_CHECKER) $(DT_CHECKER_FLAGS) -u $(srctree)/$(DT_BINDING_DIR) -p $(DT_TMP_SCHEMA) $@ || true +else +quiet_cmd_dtb = $(quiet_cmd_dtc) + cmd_dtb = $(cmd_dtc) endif -define rule_dtc - $(call cmd_and_fixdep,dtc) - $(call cmd,dtb_check) -endef - $(obj)/%.dtb: $(src)/%.dts $(DTC) $(DT_TMP_SCHEMA) FORCE - $(call if_changed_rule,dtc) + $(call if_changed_dep,dtb) $(obj)/%.dtbo: $(src)/%.dts $(DTC) FORCE $(call if_changed_dep,dtc) -- cgit v1.2.3-59-g8ed1b From b6acf807351781c3c3810df7873b3f0d793d59b2 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Thu, 30 Jun 2022 15:37:22 -0600 Subject: dt: Add a check for undocumented compatible strings in kernel Add a make target, dt_compatible_check, to extract compatible strings from kernel sources and check if they are documented by a schema. At least version v2022.08 of dtschema with dt-check-compatible is required. This check can also be run manually on specific files or directories: scripts/dtc/dt-extract-compatibles drivers/clk/ | \ xargs dt-check-compatible -v -s Documentation/devicetree/bindings/processed-schema.json Currently, there are about 3800 undocumented compatible strings. Most of these are cases where the binding is not yet converted (given there are 1900 .txt binding files remaining). Link: https://lore.kernel.org/all/20220916012510.2718170-1-robh@kernel.org/ Signed-off-by: Rob Herring --- Documentation/devicetree/bindings/Makefile | 3 ++ Makefile | 4 ++ scripts/dtc/dt-extract-compatibles | 69 ++++++++++++++++++++++++++++++ 3 files changed, 76 insertions(+) create mode 100755 scripts/dtc/dt-extract-compatibles (limited to 'scripts') diff --git a/Documentation/devicetree/bindings/Makefile b/Documentation/devicetree/bindings/Makefile index 1eaccf135b30..bf2d8a8ced77 100644 --- a/Documentation/devicetree/bindings/Makefile +++ b/Documentation/devicetree/bindings/Makefile @@ -75,3 +75,6 @@ always-$(CHECK_DT_BINDING) += $(patsubst $(srctree)/$(src)/%.yaml,%.example.dtb, # build artifacts here before they are processed by scripts/Makefile.clean clean-files = $(shell find $(obj) \( -name '*.example.dts' -o \ -name '*.example.dtb' \) -delete 2>/dev/null) + +dt_compatible_check: $(obj)/processed-schema.json + $(Q)$(srctree)/scripts/dtc/dt-extract-compatibles $(srctree) | xargs dt-check-compatible -v -s $< diff --git a/Makefile b/Makefile index f09673b6c11d..7f19e1725b2f 100644 --- a/Makefile +++ b/Makefile @@ -1419,6 +1419,10 @@ PHONY += dt_binding_check dt_binding_check: scripts_dtc $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings +PHONY += dt_compatible_check +dt_compatible_check: dt_binding_check + $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@ + # --------------------------------------------------------------------------- # Modules diff --git a/scripts/dtc/dt-extract-compatibles b/scripts/dtc/dt-extract-compatibles new file mode 100755 index 000000000000..a1119762ed08 --- /dev/null +++ b/scripts/dtc/dt-extract-compatibles @@ -0,0 +1,69 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: GPL-2.0-only + +import os +import glob +import re +import argparse + + +def parse_of_declare_macros(data): + """ Find all compatible strings in OF_DECLARE() style macros """ + compat_list = [] + # CPU_METHOD_OF_DECLARE does not have a compatible string + for m in re.finditer(r'(? Date: Wed, 27 Jul 2022 17:58:20 +0200 Subject: kallsyms: use `ARRAY_SIZE` instead of hardcoded size This removes one place where the `500` constant is hardcoded. Reviewed-by: Kees Cook Reviewed-by: Geert Stappers Reviewed-by: Greg Kroah-Hartman Signed-off-by: Boqun Feng Co-developed-by: Miguel Ojeda Signed-off-by: Miguel Ojeda --- scripts/kallsyms.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c index f18e6dfc68c5..8551513f9311 100644 --- a/scripts/kallsyms.c +++ b/scripts/kallsyms.c @@ -206,7 +206,7 @@ static struct sym_entry *read_symbol(FILE *in) rc = fscanf(in, "%llx %c %499s\n", &addr, &type, name); if (rc != 3) { - if (rc != EOF && fgets(name, 500, in) == NULL) + if (rc != EOF && fgets(name, ARRAY_SIZE(name), in) == NULL) fprintf(stderr, "Read error or end of file.\n"); return NULL; } -- cgit v1.2.3-59-g8ed1b From b471927ebf9bb54ba6e99f20848d70193e645eed Mon Sep 17 00:00:00 2001 From: Boqun Feng Date: Wed, 27 Jul 2022 20:54:19 +0200 Subject: kallsyms: avoid hardcoding buffer size This introduces `KSYM_NAME_LEN_BUFFER` in place of the previously hardcoded size of the input buffer. It will also make it easier to update the size in a single place in a later patch. Reviewed-by: Kees Cook Reviewed-by: Greg Kroah-Hartman Signed-off-by: Boqun Feng Co-developed-by: Miguel Ojeda Signed-off-by: Miguel Ojeda --- scripts/kallsyms.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c index 8551513f9311..25e2fe5fbcd4 100644 --- a/scripts/kallsyms.c +++ b/scripts/kallsyms.c @@ -27,8 +27,14 @@ #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0])) +#define _stringify_1(x) #x +#define _stringify(x) _stringify_1(x) + #define KSYM_NAME_LEN 128 +/* A substantially bigger size than the current maximum. */ +#define KSYM_NAME_LEN_BUFFER 499 + struct sym_entry { unsigned long long addr; unsigned int len; @@ -198,13 +204,13 @@ static void check_symbol_range(const char *sym, unsigned long long addr, static struct sym_entry *read_symbol(FILE *in) { - char name[500], type; + char name[KSYM_NAME_LEN_BUFFER+1], type; unsigned long long addr; unsigned int len; struct sym_entry *sym; int rc; - rc = fscanf(in, "%llx %c %499s\n", &addr, &type, name); + rc = fscanf(in, "%llx %c %" _stringify(KSYM_NAME_LEN_BUFFER) "s\n", &addr, &type, name); if (rc != 3) { if (rc != EOF && fgets(name, ARRAY_SIZE(name), in) == NULL) fprintf(stderr, "Read error or end of file.\n"); -- cgit v1.2.3-59-g8ed1b From 6e8c5bbd5e83e649251c198e743c8b9e7c48372b Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Wed, 27 Jul 2022 21:41:56 +0200 Subject: kallsyms: add static relationship between `KSYM_NAME_LEN{,_BUFFER}` This adds a static assert to ensure `KSYM_NAME_LEN_BUFFER` gets updated when `KSYM_NAME_LEN` changes. The relationship used is one that keeps the new size (512+1) close to the original buffer size (500). Reviewed-by: Greg Kroah-Hartman Co-developed-by: Boqun Feng Signed-off-by: Boqun Feng Signed-off-by: Miguel Ojeda --- scripts/kallsyms.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c index 25e2fe5fbcd4..411ff5058b51 100644 --- a/scripts/kallsyms.c +++ b/scripts/kallsyms.c @@ -32,8 +32,18 @@ #define KSYM_NAME_LEN 128 -/* A substantially bigger size than the current maximum. */ -#define KSYM_NAME_LEN_BUFFER 499 +/* + * A substantially bigger size than the current maximum. + * + * It cannot be defined as an expression because it gets stringified + * for the fscanf() format string. Therefore, a _Static_assert() is + * used instead to maintain the relationship with KSYM_NAME_LEN. + */ +#define KSYM_NAME_LEN_BUFFER 512 +_Static_assert( + KSYM_NAME_LEN_BUFFER == KSYM_NAME_LEN * 4, + "Please keep KSYM_NAME_LEN_BUFFER in sync with KSYM_NAME_LEN" +); struct sym_entry { unsigned long long addr; -- cgit v1.2.3-59-g8ed1b From 73bbb94466fd3f8b313eeb0b0467314a262dddb3 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Mon, 5 Apr 2021 04:58:39 +0200 Subject: kallsyms: support "big" kernel symbols Rust symbols can become quite long due to namespacing introduced by modules, types, traits, generics, etc. Increasing to 255 is not enough in some cases, therefore introduce longer lengths to the symbol table. In order to avoid increasing all lengths to 2 bytes (since most of them are small, including many Rust ones), use ULEB128 to keep smaller symbols in 1 byte, with the rest in 2 bytes. Reviewed-by: Kees Cook Reviewed-by: Greg Kroah-Hartman Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Co-developed-by: Gary Guo Signed-off-by: Gary Guo Co-developed-by: Boqun Feng Signed-off-by: Boqun Feng Co-developed-by: Matthew Wilcox Signed-off-by: Matthew Wilcox Signed-off-by: Miguel Ojeda --- kernel/kallsyms.c | 26 ++++++++++++++++++++++---- scripts/kallsyms.c | 29 ++++++++++++++++++++++++++--- 2 files changed, 48 insertions(+), 7 deletions(-) (limited to 'scripts') diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index 3e7e2c2ad2f7..fc5e26348d25 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -50,12 +50,20 @@ static unsigned int kallsyms_expand_symbol(unsigned int off, data = &kallsyms_names[off]; len = *data; data++; + off++; + + /* If MSB is 1, it is a "big" symbol, so needs an additional byte. */ + if ((len & 0x80) != 0) { + len = (len & 0x7F) | (*data << 7); + data++; + off++; + } /* * Update the offset to return the offset for the next symbol on * the compressed stream. */ - off += len + 1; + off += len; /* * For every byte on the compressed symbol data, copy the table @@ -108,7 +116,7 @@ static char kallsyms_get_symbol_type(unsigned int off) static unsigned int get_symbol_offset(unsigned long pos) { const u8 *name; - int i; + int i, len; /* * Use the closest marker we have. We have markers every 256 positions, @@ -122,8 +130,18 @@ static unsigned int get_symbol_offset(unsigned long pos) * so we just need to add the len to the current pointer for every * symbol we wish to skip. */ - for (i = 0; i < (pos & 0xFF); i++) - name = name + (*name) + 1; + for (i = 0; i < (pos & 0xFF); i++) { + len = *name; + + /* + * If MSB is 1, it is a "big" symbol, so we need to look into + * the next byte (and skip it, too). + */ + if ((len & 0x80) != 0) + len = ((len & 0x7F) | (name[1] << 7)) + 1; + + name = name + len + 1; + } return name - kallsyms_names; } diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c index 411ff5058b51..6502c4001f01 100644 --- a/scripts/kallsyms.c +++ b/scripts/kallsyms.c @@ -487,12 +487,35 @@ static void write_src(void) if ((i & 0xFF) == 0) markers[i >> 8] = off; - printf("\t.byte 0x%02x", table[i]->len); + /* There cannot be any symbol of length zero. */ + if (table[i]->len == 0) { + fprintf(stderr, "kallsyms failure: " + "unexpected zero symbol length\n"); + exit(EXIT_FAILURE); + } + + /* Only lengths that fit in up-to-two-byte ULEB128 are supported. */ + if (table[i]->len > 0x3FFF) { + fprintf(stderr, "kallsyms failure: " + "unexpected huge symbol length\n"); + exit(EXIT_FAILURE); + } + + /* Encode length with ULEB128. */ + if (table[i]->len <= 0x7F) { + /* Most symbols use a single byte for the length. */ + printf("\t.byte 0x%02x", table[i]->len); + off += table[i]->len + 1; + } else { + /* "Big" symbols use two bytes. */ + printf("\t.byte 0x%02x, 0x%02x", + (table[i]->len & 0x7F) | 0x80, + (table[i]->len >> 7) & 0x7F); + off += table[i]->len + 2; + } for (k = 0; k < table[i]->len; k++) printf(", 0x%02x", table[i]->sym[k]); printf("\n"); - - off += table[i]->len + 1; } printf("\n"); -- cgit v1.2.3-59-g8ed1b From b8a94bfb33952bb17fbc65f8903d242a721c533d Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Mon, 5 Apr 2021 05:03:50 +0200 Subject: kallsyms: increase maximum kernel symbol length to 512 Rust symbols can become quite long due to namespacing introduced by modules, types, traits, generics, etc. For instance, the following code: pub mod my_module { pub struct MyType; pub struct MyGenericType(T); pub trait MyTrait { fn my_method() -> u32; } impl MyTrait for MyGenericType { fn my_method() -> u32 { 42 } } } generates a symbol of length 96 when using the upcoming v0 mangling scheme: _RNvXNtCshGpAVYOtgW1_7example9my_moduleINtB2_13MyGenericTypeNtB2_6MyTypeENtB2_7MyTrait9my_method At the moment, Rust symbols may reach up to 300 in length. Setting 512 as the maximum seems like a reasonable choice to keep some headroom. Reviewed-by: Kees Cook Reviewed-by: Petr Mladek Reviewed-by: Greg Kroah-Hartman Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Co-developed-by: Gary Guo Signed-off-by: Gary Guo Co-developed-by: Boqun Feng Signed-off-by: Boqun Feng Signed-off-by: Miguel Ojeda --- include/linux/kallsyms.h | 2 +- kernel/livepatch/core.c | 4 ++-- scripts/kallsyms.c | 4 ++-- tools/include/linux/kallsyms.h | 2 +- tools/lib/perf/include/perf/event.h | 2 +- tools/lib/symbol/kallsyms.h | 2 +- 6 files changed, 8 insertions(+), 8 deletions(-) (limited to 'scripts') diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h index ad39636e0c3f..649faac31ddb 100644 --- a/include/linux/kallsyms.h +++ b/include/linux/kallsyms.h @@ -15,7 +15,7 @@ #include -#define KSYM_NAME_LEN 128 +#define KSYM_NAME_LEN 512 #define KSYM_SYMBOL_LEN (sizeof("%s+%#lx/%#lx [%s %s]") + \ (KSYM_NAME_LEN - 1) + \ 2*(BITS_PER_LONG*3/10) + (MODULE_NAME_LEN - 1) + \ diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index bc475e62279d..ec06ce59d728 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -213,7 +213,7 @@ static int klp_resolve_symbols(Elf_Shdr *sechdrs, const char *strtab, * we use the smallest/strictest upper bound possible (56, based on * the current definition of MODULE_NAME_LEN) to prevent overflows. */ - BUILD_BUG_ON(MODULE_NAME_LEN < 56 || KSYM_NAME_LEN != 128); + BUILD_BUG_ON(MODULE_NAME_LEN < 56 || KSYM_NAME_LEN != 512); relas = (Elf_Rela *) relasec->sh_addr; /* For each rela in this klp relocation section */ @@ -227,7 +227,7 @@ static int klp_resolve_symbols(Elf_Shdr *sechdrs, const char *strtab, /* Format: .klp.sym.sym_objname.sym_name,sympos */ cnt = sscanf(strtab + sym->st_name, - ".klp.sym.%55[^.].%127[^,],%lu", + ".klp.sym.%55[^.].%511[^,],%lu", sym_objname, sym_name, &sympos); if (cnt != 3) { pr_err("symbol %s has an incorrectly formatted name\n", diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c index 6502c4001f01..c4793301a27e 100644 --- a/scripts/kallsyms.c +++ b/scripts/kallsyms.c @@ -30,7 +30,7 @@ #define _stringify_1(x) #x #define _stringify(x) _stringify_1(x) -#define KSYM_NAME_LEN 128 +#define KSYM_NAME_LEN 512 /* * A substantially bigger size than the current maximum. @@ -39,7 +39,7 @@ * for the fscanf() format string. Therefore, a _Static_assert() is * used instead to maintain the relationship with KSYM_NAME_LEN. */ -#define KSYM_NAME_LEN_BUFFER 512 +#define KSYM_NAME_LEN_BUFFER 2048 _Static_assert( KSYM_NAME_LEN_BUFFER == KSYM_NAME_LEN * 4, "Please keep KSYM_NAME_LEN_BUFFER in sync with KSYM_NAME_LEN" diff --git a/tools/include/linux/kallsyms.h b/tools/include/linux/kallsyms.h index efb6c3f5f2a9..5a37ccbec54f 100644 --- a/tools/include/linux/kallsyms.h +++ b/tools/include/linux/kallsyms.h @@ -6,7 +6,7 @@ #include #include -#define KSYM_NAME_LEN 128 +#define KSYM_NAME_LEN 512 struct module; diff --git a/tools/lib/perf/include/perf/event.h b/tools/lib/perf/include/perf/event.h index 93bf93a59c99..d8ae4e944467 100644 --- a/tools/lib/perf/include/perf/event.h +++ b/tools/lib/perf/include/perf/event.h @@ -97,7 +97,7 @@ struct perf_record_throttle { }; #ifndef KSYM_NAME_LEN -#define KSYM_NAME_LEN 256 +#define KSYM_NAME_LEN 512 #endif struct perf_record_ksymbol { diff --git a/tools/lib/symbol/kallsyms.h b/tools/lib/symbol/kallsyms.h index 72ab9870454b..542f9b059c3b 100644 --- a/tools/lib/symbol/kallsyms.h +++ b/tools/lib/symbol/kallsyms.h @@ -7,7 +7,7 @@ #include #ifndef KSYM_NAME_LEN -#define KSYM_NAME_LEN 256 +#define KSYM_NAME_LEN 512 #endif static inline u8 kallsyms2elf_binding(char type) -- cgit v1.2.3-59-g8ed1b From de48fa1a01e7752135c960a20d6c3b26544a8120 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 22 May 2022 03:11:08 +0200 Subject: scripts: checkpatch: diagnose uses of `%pA` in the C side as errors The `%pA` format specifier is only intended to be used from Rust. `checkpatch.pl` already gives a warning for invalid specificers: WARNING: Invalid vsprintf pointer extension '%pA' This makes it an error and introduces an explanatory message: ERROR: Invalid vsprintf pointer extension '%pA' - '%pA' is only intended to be used from Rust code Suggested-by: Kees Cook Reviewed-by: Greg Kroah-Hartman Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Co-developed-by: Joe Perches Signed-off-by: Joe Perches Signed-off-by: Miguel Ojeda --- scripts/checkpatch.pl | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 79e759aac543..74a769310adf 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -6783,15 +6783,19 @@ sub process { } if ($bad_specifier ne "") { my $stat_real = get_stat_real($linenr, $lc); + my $msg_level = \&WARN; my $ext_type = "Invalid"; my $use = ""; if ($bad_specifier =~ /p[Ff]/) { $use = " - use %pS instead"; $use =~ s/pS/ps/ if ($bad_specifier =~ /pf/); + } elsif ($bad_specifier =~ /pA/) { + $use = " - '%pA' is only intended to be used from Rust code"; + $msg_level = \&ERROR; } - WARN("VSPRINTF_POINTER_EXTENSION", - "$ext_type vsprintf pointer extension '$bad_specifier'$use\n" . "$here\n$stat_real\n"); + &{$msg_level}("VSPRINTF_POINTER_EXTENSION", + "$ext_type vsprintf pointer extension '$bad_specifier'$use\n" . "$here\n$stat_real\n"); } } } -- cgit v1.2.3-59-g8ed1b From d1d84b5f73888ccb9fc148dfc3cb3e15d3604d65 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 22 May 2022 17:22:58 +0200 Subject: scripts: checkpatch: enable language-independent checks for Rust Include Rust in the "source code files" category, so that the language-independent tests are checked for Rust too, and teach `checkpatch` about the comment style for Rust files. This enables the malformed SPDX check, the misplaced SPDX license tag check, the long line checks, the lines without a newline check and the embedded filename check. Reviewed-by: Kees Cook Reviewed-by: Greg Kroah-Hartman Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Signed-off-by: Miguel Ojeda --- scripts/checkpatch.pl | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 74a769310adf..b5ed31d631fa 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -3616,7 +3616,7 @@ sub process { my $comment = ""; if ($realfile =~ /\.(h|s|S)$/) { $comment = '/*'; - } elsif ($realfile =~ /\.(c|dts|dtsi)$/) { + } elsif ($realfile =~ /\.(c|rs|dts|dtsi)$/) { $comment = '//'; } elsif (($checklicenseline == 2) || $realfile =~ /\.(sh|pl|py|awk|tc|yaml)$/) { $comment = '#'; @@ -3664,7 +3664,7 @@ sub process { } # check we are in a valid source file if not then ignore this hunk - next if ($realfile !~ /\.(h|c|s|S|sh|dtsi|dts)$/); + next if ($realfile !~ /\.(h|c|rs|s|S|sh|dtsi|dts)$/); # check for using SPDX-License-Identifier on the wrong line number if ($realline != $checklicenseline && -- cgit v1.2.3-59-g8ed1b From 99115db4ecc87af73415939439ec604ea0531e6f Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 5 Dec 2021 19:00:43 +0100 Subject: scripts: decode_stacktrace: demangle Rust symbols Recent versions of both Binutils (`c++filt`) and LLVM (`llvm-cxxfilt`) provide Rust v0 mangling support. Reviewed-by: Kees Cook Reviewed-by: Greg Kroah-Hartman Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Signed-off-by: Miguel Ojeda --- scripts/decode_stacktrace.sh | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'scripts') diff --git a/scripts/decode_stacktrace.sh b/scripts/decode_stacktrace.sh index 7075e26ab2c4..564c5632e1a2 100755 --- a/scripts/decode_stacktrace.sh +++ b/scripts/decode_stacktrace.sh @@ -8,6 +8,14 @@ usage() { echo " $0 -r | [|auto] []" } +# Try to find a Rust demangler +if type llvm-cxxfilt >/dev/null 2>&1 ; then + cppfilt=llvm-cxxfilt +elif type c++filt >/dev/null 2>&1 ; then + cppfilt=c++filt + cppfilt_opts=-i +fi + if [[ $1 == "-r" ]] ; then vmlinux="" basepath="auto" @@ -180,6 +188,12 @@ parse_symbol() { # In the case of inlines, move everything to same line code=${code//$'\n'/' '} + # Demangle if the name looks like a Rust symbol and if + # we got a Rust demangler + if [[ $name =~ ^_R && $cppfilt != "" ]] ; then + name=$("$cppfilt" "$cppfilt_opts" "$name") + fi + # Replace old address with pretty line numbers symbol="$segment$name ($code)" } -- cgit v1.2.3-59-g8ed1b From 8c4555ccc55cf90e1e3eb2507be3c354f3d15839 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sat, 3 Jul 2021 17:26:15 +0200 Subject: scripts: add `generate_rust_analyzer.py` MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The `generate_rust_analyzer.py` script generates the configuration file (`rust-project.json`) for rust-analyzer. rust-analyzer is a modular compiler frontend for the Rust language. It provides an LSP server which can be used in editors such as VS Code, Emacs or Vim. Reviewed-by: Kees Cook Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Finn Behrens Signed-off-by: Finn Behrens Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Co-developed-by: Gary Guo Signed-off-by: Gary Guo Co-developed-by: Boris-Chengbiao Zhou Signed-off-by: Boris-Chengbiao Zhou Co-developed-by: Björn Roy Baron Signed-off-by: Björn Roy Baron Signed-off-by: Miguel Ojeda --- .gitignore | 3 + scripts/generate_rust_analyzer.py | 135 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 138 insertions(+) create mode 100755 scripts/generate_rust_analyzer.py (limited to 'scripts') diff --git a/.gitignore b/.gitignore index 265959544978..80989914c97d 100644 --- a/.gitignore +++ b/.gitignore @@ -162,3 +162,6 @@ x509.genkey # Documentation toolchain sphinx_*/ + +# Rust analyzer configuration +/rust-project.json diff --git a/scripts/generate_rust_analyzer.py b/scripts/generate_rust_analyzer.py new file mode 100755 index 000000000000..75bb611bd751 --- /dev/null +++ b/scripts/generate_rust_analyzer.py @@ -0,0 +1,135 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: GPL-2.0 +"""generate_rust_analyzer - Generates the `rust-project.json` file for `rust-analyzer`. +""" + +import argparse +import json +import logging +import pathlib +import sys + +def generate_crates(srctree, objtree, sysroot_src): + # Generate the configuration list. + cfg = [] + with open(objtree / "include" / "generated" / "rustc_cfg") as fd: + for line in fd: + line = line.replace("--cfg=", "") + line = line.replace("\n", "") + cfg.append(line) + + # Now fill the crates list -- dependencies need to come first. + # + # Avoid O(n^2) iterations by keeping a map of indexes. + crates = [] + crates_indexes = {} + + def append_crate(display_name, root_module, deps, cfg=[], is_workspace_member=True, is_proc_macro=False): + crates_indexes[display_name] = len(crates) + crates.append({ + "display_name": display_name, + "root_module": str(root_module), + "is_workspace_member": is_workspace_member, + "is_proc_macro": is_proc_macro, + "deps": [{"crate": crates_indexes[dep], "name": dep} for dep in deps], + "cfg": cfg, + "edition": "2021", + "env": { + "RUST_MODFILE": "This is only for rust-analyzer" + } + }) + + # First, the ones in `rust/` since they are a bit special. + append_crate( + "core", + sysroot_src / "core" / "src" / "lib.rs", + [], + is_workspace_member=False, + ) + + append_crate( + "compiler_builtins", + srctree / "rust" / "compiler_builtins.rs", + [], + ) + + append_crate( + "alloc", + srctree / "rust" / "alloc" / "lib.rs", + ["core", "compiler_builtins"], + ) + + append_crate( + "macros", + srctree / "rust" / "macros" / "lib.rs", + [], + is_proc_macro=True, + ) + crates[-1]["proc_macro_dylib_path"] = "rust/libmacros.so" + + append_crate( + "bindings", + srctree / "rust"/ "bindings" / "lib.rs", + ["core"], + cfg=cfg, + ) + crates[-1]["env"]["OBJTREE"] = str(objtree.resolve(True)) + + append_crate( + "kernel", + srctree / "rust" / "kernel" / "lib.rs", + ["core", "alloc", "macros", "bindings"], + cfg=cfg, + ) + crates[-1]["source"] = { + "include_dirs": [ + str(srctree / "rust" / "kernel"), + str(objtree / "rust") + ], + "exclude_dirs": [], + } + + # Then, the rest outside of `rust/`. + # + # We explicitly mention the top-level folders we want to cover. + for folder in ("samples", "drivers"): + for path in (srctree / folder).rglob("*.rs"): + logging.info("Checking %s", path) + name = path.name.replace(".rs", "") + + # Skip those that are not crate roots. + if f"{name}.o" not in open(path.parent / "Makefile").read(): + continue + + logging.info("Adding %s", name) + append_crate( + name, + path, + ["core", "alloc", "kernel"], + cfg=cfg, + ) + + return crates + +def main(): + parser = argparse.ArgumentParser() + parser.add_argument('--verbose', '-v', action='store_true') + parser.add_argument("srctree", type=pathlib.Path) + parser.add_argument("objtree", type=pathlib.Path) + parser.add_argument("sysroot_src", type=pathlib.Path) + args = parser.parse_args() + + logging.basicConfig( + format="[%(asctime)s] [%(levelname)s] %(message)s", + level=logging.INFO if args.verbose else logging.WARNING + ) + + rust_project = { + "crates": generate_crates(args.srctree, args.objtree, args.sysroot_src), + "sysroot_src": str(args.sysroot_src), + } + + json.dump(rust_project, sys.stdout, sort_keys=True, indent=4) + +if __name__ == "__main__": + main() -- cgit v1.2.3-59-g8ed1b From 9a8ff24ce584ad9895f9416fe8fad6f8842f758d Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Thu, 4 Aug 2022 12:20:37 +0200 Subject: scripts: add `generate_rust_target.rs` This script takes care of generating the custom target specification file for `rustc`, based on the kernel configuration. It also serves as an example of a Rust host program. A dummy architecture is kept in this patch so that a later patch adds x86 support on top with as few changes as possible. Reviewed-by: Kees Cook Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Co-developed-by: David Gow Signed-off-by: David Gow Signed-off-by: Miguel Ojeda --- scripts/.gitignore | 1 + scripts/generate_rust_target.rs | 171 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 172 insertions(+) create mode 100644 scripts/generate_rust_target.rs (limited to 'scripts') diff --git a/scripts/.gitignore b/scripts/.gitignore index eed308bef604..b7aec8eb1bd4 100644 --- a/scripts/.gitignore +++ b/scripts/.gitignore @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only /asn1_compiler /bin2c +/generate_rust_target /insert-sys-cert /kallsyms /module.lds diff --git a/scripts/generate_rust_target.rs b/scripts/generate_rust_target.rs new file mode 100644 index 000000000000..7256c9606cf0 --- /dev/null +++ b/scripts/generate_rust_target.rs @@ -0,0 +1,171 @@ +// SPDX-License-Identifier: GPL-2.0 + +//! The custom target specification file generator for `rustc`. +//! +//! To configure a target from scratch, a JSON-encoded file has to be passed +//! to `rustc` (introduced in [RFC 131]). These options and the file itself are +//! unstable. Eventually, `rustc` should provide a way to do this in a stable +//! manner. For instance, via command-line arguments. Therefore, this file +//! should avoid using keys which can be set via `-C` or `-Z` options. +//! +//! [RFC 131]: https://rust-lang.github.io/rfcs/0131-target-specification.html + +use std::{ + collections::HashMap, + fmt::{Display, Formatter, Result}, + io::BufRead, +}; + +enum Value { + Boolean(bool), + Number(i32), + String(String), + Object(Object), +} + +type Object = Vec<(String, Value)>; + +/// Minimal "almost JSON" generator (e.g. no `null`s, no arrays, no escaping), +/// enough for this purpose. +impl Display for Value { + fn fmt(&self, formatter: &mut Formatter<'_>) -> Result { + match self { + Value::Boolean(boolean) => write!(formatter, "{}", boolean), + Value::Number(number) => write!(formatter, "{}", number), + Value::String(string) => write!(formatter, "\"{}\"", string), + Value::Object(object) => { + formatter.write_str("{")?; + if let [ref rest @ .., ref last] = object[..] { + for (key, value) in rest { + write!(formatter, "\"{}\": {},", key, value)?; + } + write!(formatter, "\"{}\": {}", last.0, last.1)?; + } + formatter.write_str("}") + } + } + } +} + +struct TargetSpec(Object); + +impl TargetSpec { + fn new() -> TargetSpec { + TargetSpec(Vec::new()) + } +} + +trait Push { + fn push(&mut self, key: &str, value: T); +} + +impl Push for TargetSpec { + fn push(&mut self, key: &str, value: bool) { + self.0.push((key.to_string(), Value::Boolean(value))); + } +} + +impl Push for TargetSpec { + fn push(&mut self, key: &str, value: i32) { + self.0.push((key.to_string(), Value::Number(value))); + } +} + +impl Push for TargetSpec { + fn push(&mut self, key: &str, value: String) { + self.0.push((key.to_string(), Value::String(value))); + } +} + +impl Push<&str> for TargetSpec { + fn push(&mut self, key: &str, value: &str) { + self.push(key, value.to_string()); + } +} + +impl Push for TargetSpec { + fn push(&mut self, key: &str, value: Object) { + self.0.push((key.to_string(), Value::Object(value))); + } +} + +impl Display for TargetSpec { + fn fmt(&self, formatter: &mut Formatter<'_>) -> Result { + // We add some newlines for clarity. + formatter.write_str("{\n")?; + if let [ref rest @ .., ref last] = self.0[..] { + for (key, value) in rest { + write!(formatter, " \"{}\": {},\n", key, value)?; + } + write!(formatter, " \"{}\": {}\n", last.0, last.1)?; + } + formatter.write_str("}") + } +} + +struct KernelConfig(HashMap); + +impl KernelConfig { + /// Parses `include/config/auto.conf` from `stdin`. + fn from_stdin() -> KernelConfig { + let mut result = HashMap::new(); + + let stdin = std::io::stdin(); + let mut handle = stdin.lock(); + let mut line = String::new(); + + loop { + line.clear(); + + if handle.read_line(&mut line).unwrap() == 0 { + break; + } + + if line.starts_with('#') { + continue; + } + + let (key, value) = line.split_once('=').expect("Missing `=` in line."); + result.insert(key.to_string(), value.trim_end_matches('\n').to_string()); + } + + KernelConfig(result) + } + + /// Does the option exist in the configuration (any value)? + /// + /// The argument must be passed without the `CONFIG_` prefix. + /// This avoids repetition and it also avoids `fixdep` making us + /// depend on it. + fn has(&self, option: &str) -> bool { + let option = "CONFIG_".to_owned() + option; + self.0.contains_key(&option) + } +} + +fn main() { + let cfg = KernelConfig::from_stdin(); + let mut ts = TargetSpec::new(); + + // `llvm-target`s are taken from `scripts/Makefile.clang`. + if cfg.has("DUMMY_ARCH") { + ts.push("arch", "dummy_arch"); + } else { + panic!("Unsupported architecture"); + } + + ts.push("emit-debug-gdb-scripts", false); + ts.push("frame-pointer", "may-omit"); + ts.push( + "stack-probes", + vec![("kind".to_string(), Value::String("none".to_string()))], + ); + + // Everything else is LE, whether `CPU_LITTLE_ENDIAN` is declared or not + // (e.g. x86). It is also `rustc`'s default. + if cfg.has("CPU_BIG_ENDIAN") { + ts.push("target-endian", "big"); + } + + println!("{}", ts); +} -- cgit v1.2.3-59-g8ed1b From 78521f3399abce9bb9db16d848044be873e117ac Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Thu, 4 Aug 2022 12:25:53 +0200 Subject: scripts: add `rust_is_available.sh` This script tests whether the Rust toolchain requirements are in place to enable Rust support. It uses `min-tool-version.sh` to fetch the version numbers. The build system will call it to set `CONFIG_RUST_IS_AVAILABLE` in a later patch. It also has an option (`-v`) to explain what is missing, which is useful to set up the development environment. This is used via the `make rustavailable` target added in a later patch. Reviewed-by: Kees Cook Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Co-developed-by: Finn Behrens Signed-off-by: Finn Behrens Co-developed-by: Miguel Cano Signed-off-by: Miguel Cano Co-developed-by: Tiago Lam Signed-off-by: Tiago Lam Signed-off-by: Miguel Ojeda --- scripts/min-tool-version.sh | 6 + scripts/rust_is_available.sh | 160 +++++++++++++++++++++++++++ scripts/rust_is_available_bindgen_libclang.h | 2 + 3 files changed, 168 insertions(+) create mode 100755 scripts/rust_is_available.sh create mode 100644 scripts/rust_is_available_bindgen_libclang.h (limited to 'scripts') diff --git a/scripts/min-tool-version.sh b/scripts/min-tool-version.sh index 250925aab101..b6593eac5003 100755 --- a/scripts/min-tool-version.sh +++ b/scripts/min-tool-version.sh @@ -30,6 +30,12 @@ llvm) echo 11.0.0 fi ;; +rustc) + echo 1.62.0 + ;; +bindgen) + echo 0.56.0 + ;; *) echo "$1: unknown tool" >&2 exit 1 diff --git a/scripts/rust_is_available.sh b/scripts/rust_is_available.sh new file mode 100755 index 000000000000..aebbf1913970 --- /dev/null +++ b/scripts/rust_is_available.sh @@ -0,0 +1,160 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# +# Tests whether a suitable Rust toolchain is available. +# +# Pass `-v` for human output and more checks (as warnings). + +set -e + +min_tool_version=$(dirname $0)/min-tool-version.sh + +# Convert the version string x.y.z to a canonical up-to-7-digits form. +# +# Note that this function uses one more digit (compared to other +# instances in other version scripts) to give a bit more space to +# `rustc` since it will reach 1.100.0 in late 2026. +get_canonical_version() +{ + IFS=. + set -- $1 + echo $((100000 * $1 + 100 * $2 + $3)) +} + +# Check that the Rust compiler exists. +if ! command -v "$RUSTC" >/dev/null; then + if [ "$1" = -v ]; then + echo >&2 "***" + echo >&2 "*** Rust compiler '$RUSTC' could not be found." + echo >&2 "***" + fi + exit 1 +fi + +# Check that the Rust bindings generator exists. +if ! command -v "$BINDGEN" >/dev/null; then + if [ "$1" = -v ]; then + echo >&2 "***" + echo >&2 "*** Rust bindings generator '$BINDGEN' could not be found." + echo >&2 "***" + fi + exit 1 +fi + +# Check that the Rust compiler version is suitable. +# +# Non-stable and distributions' versions may have a version suffix, e.g. `-dev`. +rust_compiler_version=$( \ + LC_ALL=C "$RUSTC" --version 2>/dev/null \ + | head -n 1 \ + | grep -oE '[0-9]+\.[0-9]+\.[0-9]+' \ +) +rust_compiler_min_version=$($min_tool_version rustc) +rust_compiler_cversion=$(get_canonical_version $rust_compiler_version) +rust_compiler_min_cversion=$(get_canonical_version $rust_compiler_min_version) +if [ "$rust_compiler_cversion" -lt "$rust_compiler_min_cversion" ]; then + if [ "$1" = -v ]; then + echo >&2 "***" + echo >&2 "*** Rust compiler '$RUSTC' is too old." + echo >&2 "*** Your version: $rust_compiler_version" + echo >&2 "*** Minimum version: $rust_compiler_min_version" + echo >&2 "***" + fi + exit 1 +fi +if [ "$1" = -v ] && [ "$rust_compiler_cversion" -gt "$rust_compiler_min_cversion" ]; then + echo >&2 "***" + echo >&2 "*** Rust compiler '$RUSTC' is too new. This may or may not work." + echo >&2 "*** Your version: $rust_compiler_version" + echo >&2 "*** Expected version: $rust_compiler_min_version" + echo >&2 "***" +fi + +# Check that the Rust bindings generator is suitable. +# +# Non-stable and distributions' versions may have a version suffix, e.g. `-dev`. +rust_bindings_generator_version=$( \ + LC_ALL=C "$BINDGEN" --version 2>/dev/null \ + | head -n 1 \ + | grep -oE '[0-9]+\.[0-9]+\.[0-9]+' \ +) +rust_bindings_generator_min_version=$($min_tool_version bindgen) +rust_bindings_generator_cversion=$(get_canonical_version $rust_bindings_generator_version) +rust_bindings_generator_min_cversion=$(get_canonical_version $rust_bindings_generator_min_version) +if [ "$rust_bindings_generator_cversion" -lt "$rust_bindings_generator_min_cversion" ]; then + if [ "$1" = -v ]; then + echo >&2 "***" + echo >&2 "*** Rust bindings generator '$BINDGEN' is too old." + echo >&2 "*** Your version: $rust_bindings_generator_version" + echo >&2 "*** Minimum version: $rust_bindings_generator_min_version" + echo >&2 "***" + fi + exit 1 +fi +if [ "$1" = -v ] && [ "$rust_bindings_generator_cversion" -gt "$rust_bindings_generator_min_cversion" ]; then + echo >&2 "***" + echo >&2 "*** Rust bindings generator '$BINDGEN' is too new. This may or may not work." + echo >&2 "*** Your version: $rust_bindings_generator_version" + echo >&2 "*** Expected version: $rust_bindings_generator_min_version" + echo >&2 "***" +fi + +# Check that the `libclang` used by the Rust bindings generator is suitable. +bindgen_libclang_version=$( \ + LC_ALL=C "$BINDGEN" $(dirname $0)/rust_is_available_bindgen_libclang.h 2>&1 >/dev/null \ + | grep -F 'clang version ' \ + | grep -oE '[0-9]+\.[0-9]+\.[0-9]+' \ + | head -n 1 \ +) +bindgen_libclang_min_version=$($min_tool_version llvm) +bindgen_libclang_cversion=$(get_canonical_version $bindgen_libclang_version) +bindgen_libclang_min_cversion=$(get_canonical_version $bindgen_libclang_min_version) +if [ "$bindgen_libclang_cversion" -lt "$bindgen_libclang_min_cversion" ]; then + if [ "$1" = -v ]; then + echo >&2 "***" + echo >&2 "*** libclang (used by the Rust bindings generator '$BINDGEN') is too old." + echo >&2 "*** Your version: $bindgen_libclang_version" + echo >&2 "*** Minimum version: $bindgen_libclang_min_version" + echo >&2 "***" + fi + exit 1 +fi + +# If the C compiler is Clang, then we can also check whether its version +# matches the `libclang` version used by the Rust bindings generator. +# +# In the future, we might be able to perform a full version check, see +# https://github.com/rust-lang/rust-bindgen/issues/2138. +if [ "$1" = -v ]; then + cc_name=$($(dirname $0)/cc-version.sh "$CC" | cut -f1 -d' ') + if [ "$cc_name" = Clang ]; then + clang_version=$( \ + LC_ALL=C "$CC" --version 2>/dev/null \ + | sed -nE '1s:.*version ([0-9]+\.[0-9]+\.[0-9]+).*:\1:p' + ) + if [ "$clang_version" != "$bindgen_libclang_version" ]; then + echo >&2 "***" + echo >&2 "*** libclang (used by the Rust bindings generator '$BINDGEN')" + echo >&2 "*** version does not match Clang's. This may be a problem." + echo >&2 "*** libclang version: $bindgen_libclang_version" + echo >&2 "*** Clang version: $clang_version" + echo >&2 "***" + fi + fi +fi + +# Check that the source code for the `core` standard library exists. +# +# `$KRUSTFLAGS` is passed in case the user added `--sysroot`. +rustc_sysroot=$("$RUSTC" $KRUSTFLAGS --print sysroot) +rustc_src=${RUST_LIB_SRC:-"$rustc_sysroot/lib/rustlib/src/rust/library"} +rustc_src_core="$rustc_src/core/src/lib.rs" +if [ ! -e "$rustc_src_core" ]; then + if [ "$1" = -v ]; then + echo >&2 "***" + echo >&2 "*** Source code for the 'core' standard library could not be found" + echo >&2 "*** at '$rustc_src_core'." + echo >&2 "***" + fi + exit 1 +fi diff --git a/scripts/rust_is_available_bindgen_libclang.h b/scripts/rust_is_available_bindgen_libclang.h new file mode 100644 index 000000000000..0ef6db10d674 --- /dev/null +++ b/scripts/rust_is_available_bindgen_libclang.h @@ -0,0 +1,2 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#pragma message("clang version " __clang_version__) -- cgit v1.2.3-59-g8ed1b From e4b69cb9a99a567d1611f9cced92f475ae224cdb Mon Sep 17 00:00:00 2001 From: Daniel Xu Date: Thu, 4 Aug 2022 12:55:07 +0200 Subject: scripts: add `is_rust_module.sh` This script is used to detect whether a kernel module is written in Rust. It will later be used to disable BTF generation on Rust modules as BTF does not yet support Rust. Reviewed-by: Kees Cook Reviewed-by: Greg Kroah-Hartman Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Signed-off-by: Daniel Xu Co-developed-by: Miguel Ojeda Signed-off-by: Miguel Ojeda --- scripts/is_rust_module.sh | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) create mode 100755 scripts/is_rust_module.sh (limited to 'scripts') diff --git a/scripts/is_rust_module.sh b/scripts/is_rust_module.sh new file mode 100755 index 000000000000..28b3831a7593 --- /dev/null +++ b/scripts/is_rust_module.sh @@ -0,0 +1,16 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# +# is_rust_module.sh module.ko +# +# Returns `0` if `module.ko` is a Rust module, `1` otherwise. + +set -e + +# Using the `16_` prefix ensures other symbols with the same substring +# are not picked up (even if it would be unlikely). The last part is +# used just in case LLVM decides to use the `.` suffix. +# +# In the future, checking for the `.comment` section may be another +# option, see https://github.com/rust-lang/rust/pull/97550. +${NM} "$*" | grep -qE '^[0-9a-fA-F]+ r _R[^[:space:]]+16___IS_RUST_MODULE[^[:space:]]*$' -- cgit v1.2.3-59-g8ed1b From 2f7ab1267dc9b2d1f29695aff3211c87483480f3 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sat, 3 Jul 2021 16:42:57 +0200 Subject: Kbuild: add Rust support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Having most of the new files in place, we now enable Rust support in the build system, including `Kconfig` entries related to Rust, the Rust configuration printer and a few other bits. Reviewed-by: Kees Cook Reviewed-by: Nick Desaulniers Tested-by: Nick Desaulniers Reviewed-by: Greg Kroah-Hartman Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Finn Behrens Signed-off-by: Finn Behrens Co-developed-by: Adam Bratschi-Kaye Signed-off-by: Adam Bratschi-Kaye Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Co-developed-by: Michael Ellerman Signed-off-by: Michael Ellerman Co-developed-by: Sven Van Asbroeck Signed-off-by: Sven Van Asbroeck Co-developed-by: Gary Guo Signed-off-by: Gary Guo Co-developed-by: Boris-Chengbiao Zhou Signed-off-by: Boris-Chengbiao Zhou Co-developed-by: Boqun Feng Signed-off-by: Boqun Feng Co-developed-by: Douglas Su Signed-off-by: Douglas Su Co-developed-by: Dariusz Sosnowski Signed-off-by: Dariusz Sosnowski Co-developed-by: Antonio Terceiro Signed-off-by: Antonio Terceiro Co-developed-by: Daniel Xu Signed-off-by: Daniel Xu Co-developed-by: Björn Roy Baron Signed-off-by: Björn Roy Baron Co-developed-by: Martin Rodriguez Reboredo Signed-off-by: Martin Rodriguez Reboredo Signed-off-by: Miguel Ojeda --- .gitignore | 2 + Makefile | 172 ++++++++++++++++++- arch/Kconfig | 6 + include/linux/compiler_types.h | 6 +- init/Kconfig | 46 ++++- kernel/configs/rust.config | 1 + lib/Kconfig.debug | 34 ++++ rust/.gitignore | 8 + rust/Makefile | 381 +++++++++++++++++++++++++++++++++++++++++ rust/bindgen_parameters | 21 +++ scripts/Kconfig.include | 6 +- scripts/Makefile | 3 + scripts/Makefile.build | 60 +++++++ scripts/Makefile.debug | 8 + scripts/Makefile.host | 34 +++- scripts/Makefile.lib | 12 ++ scripts/Makefile.modfinal | 8 +- scripts/cc-version.sh | 12 +- scripts/kconfig/confdata.c | 75 ++++++++ 19 files changed, 869 insertions(+), 26 deletions(-) create mode 100644 kernel/configs/rust.config create mode 100644 rust/.gitignore create mode 100644 rust/Makefile create mode 100644 rust/bindgen_parameters (limited to 'scripts') diff --git a/.gitignore b/.gitignore index 97e085d613a2..5da004814678 100644 --- a/.gitignore +++ b/.gitignore @@ -37,6 +37,8 @@ *.o *.o.* *.patch +*.rmeta +*.rsi *.s *.so *.so.dbg diff --git a/Makefile b/Makefile index 647a42a1f800..c759ee315254 100644 --- a/Makefile +++ b/Makefile @@ -120,6 +120,15 @@ endif export KBUILD_CHECKSRC +# Enable "clippy" (a linter) as part of the Rust compilation. +# +# Use 'make CLIPPY=1' to enable it. +ifeq ("$(origin CLIPPY)", "command line") + KBUILD_CLIPPY := $(CLIPPY) +endif + +export KBUILD_CLIPPY + # Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the # directory of external module to build. Setting M= takes precedence. ifeq ("$(origin M)", "command line") @@ -270,14 +279,14 @@ no-dot-config-targets := $(clean-targets) \ cscope gtags TAGS tags help% %docs check% coccicheck \ $(version_h) headers headers_% archheaders archscripts \ %asm-generic kernelversion %src-pkg dt_binding_check \ - outputmakefile + outputmakefile rustavailable rustfmt rustfmtcheck # Installation targets should not require compiler. Unfortunately, vdso_install # is an exception where build artifacts may be updated. This must be fixed. no-compiler-targets := $(no-dot-config-targets) install dtbs_install \ headers_install modules_install kernelrelease image_name no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \ image_name -single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/ +single-targets := %.a %.i %.rsi %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/ config-build := mixed-build := @@ -439,6 +448,7 @@ else HOSTCC = gcc HOSTCXX = g++ endif +HOSTRUSTC = rustc HOSTPKG_CONFIG = pkg-config KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \ @@ -447,8 +457,26 @@ KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \ KBUILD_USERCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS) KBUILD_USERLDFLAGS := $(USERLDFLAGS) +# These flags apply to all Rust code in the tree, including the kernel and +# host programs. +export rust_common_flags := --edition=2021 \ + -Zbinary_dep_depinfo=y \ + -Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \ + -Dunreachable_pub -Dnon_ascii_idents \ + -Wmissing_docs \ + -Drustdoc::missing_crate_level_docs \ + -Dclippy::correctness -Dclippy::style \ + -Dclippy::suspicious -Dclippy::complexity \ + -Dclippy::perf \ + -Dclippy::let_unit_value -Dclippy::mut_mut \ + -Dclippy::needless_bitwise_bool \ + -Dclippy::needless_continue \ + -Wclippy::dbg_macro + KBUILD_HOSTCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS) KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS) +KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \ + -Zallow-features= $(HOSTRUSTFLAGS) KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS) KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS) @@ -473,6 +501,12 @@ OBJDUMP = $(CROSS_COMPILE)objdump READELF = $(CROSS_COMPILE)readelf STRIP = $(CROSS_COMPILE)strip endif +RUSTC = rustc +RUSTDOC = rustdoc +RUSTFMT = rustfmt +CLIPPY_DRIVER = clippy-driver +BINDGEN = bindgen +CARGO = cargo PAHOLE = pahole RESOLVE_BTFIDS = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids LEX = flex @@ -498,9 +532,11 @@ CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \ -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF) NOSTDINC_FLAGS := CFLAGS_MODULE = +RUSTFLAGS_MODULE = AFLAGS_MODULE = LDFLAGS_MODULE = CFLAGS_KERNEL = +RUSTFLAGS_KERNEL = AFLAGS_KERNEL = LDFLAGS_vmlinux = @@ -529,15 +565,43 @@ KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \ -Werror=return-type -Wno-format-security \ -std=gnu11 KBUILD_CPPFLAGS := -D__KERNEL__ +KBUILD_RUSTFLAGS := $(rust_common_flags) \ + --target=$(objtree)/rust/target.json \ + -Cpanic=abort -Cembed-bitcode=n -Clto=n \ + -Cforce-unwind-tables=n -Ccodegen-units=1 \ + -Csymbol-mangling-version=v0 \ + -Crelocation-model=static \ + -Zfunction-sections=n \ + -Dclippy::float_arithmetic + KBUILD_AFLAGS_KERNEL := KBUILD_CFLAGS_KERNEL := +KBUILD_RUSTFLAGS_KERNEL := KBUILD_AFLAGS_MODULE := -DMODULE KBUILD_CFLAGS_MODULE := -DMODULE +KBUILD_RUSTFLAGS_MODULE := --cfg MODULE KBUILD_LDFLAGS_MODULE := KBUILD_LDFLAGS := CLANG_FLAGS := +ifeq ($(KBUILD_CLIPPY),1) + RUSTC_OR_CLIPPY_QUIET := CLIPPY + RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER) +else + RUSTC_OR_CLIPPY_QUIET := RUSTC + RUSTC_OR_CLIPPY = $(RUSTC) +endif + +ifdef RUST_LIB_SRC + export RUST_LIB_SRC +endif + +# Allows the usage of unstable features in stable compilers. +export RUSTC_BOOTSTRAP := 1 + export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG +export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO +export HOSTRUSTC KBUILD_HOSTRUSTFLAGS export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD @@ -546,9 +610,10 @@ export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE +export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE -export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE -export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL +export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE +export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL export PAHOLE_FLAGS # Files to ignore in find ... statements @@ -729,7 +794,7 @@ $(KCONFIG_CONFIG): # # Do not use $(call cmd,...) here. That would suppress prompts from syncconfig, # so you cannot notice that Kconfig is waiting for the user input. -%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG) +%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG) $(Q)$(kecho) " SYNC $@" $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig else # !may-sync-config @@ -758,10 +823,17 @@ KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member) ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE KBUILD_CFLAGS += -O2 +KBUILD_RUSTFLAGS += -Copt-level=2 else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE KBUILD_CFLAGS += -Os +KBUILD_RUSTFLAGS += -Copt-level=s endif +# Always set `debug-assertions` and `overflow-checks` because their default +# depends on `opt-level` and `debug-assertions`, respectively. +KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n) +KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n) + # Tell gcc to never replace conditional load with a non-conditional one ifdef CONFIG_CC_IS_GCC # gcc-10 renamed --param=allow-store-data-races=0 to @@ -792,6 +864,9 @@ KBUILD_CFLAGS-$(CONFIG_WERROR) += -Werror KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH) +KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings +KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y) + ifdef CONFIG_CC_IS_CLANG KBUILD_CPPFLAGS += -Qunused-arguments # The kernel builds with '-std=gnu11' so use of GNU extensions is acceptable. @@ -812,12 +887,15 @@ KBUILD_CFLAGS += $(call cc-disable-warning, dangling-pointer) ifdef CONFIG_FRAME_POINTER KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls +KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y else # Some targets (ARM with Thumb2, for example), can't be built with frame # pointers. For those, we don't have FUNCTION_TRACER automatically # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is # incompatible with -fomit-frame-pointer with current GCC, so we don't use # -fomit-frame-pointer with FUNCTION_TRACER. +# In the Rust target specification, "frame-pointer" is set explicitly +# to "may-omit". ifndef CONFIG_FUNCTION_TRACER KBUILD_CFLAGS += -fomit-frame-pointer endif @@ -882,8 +960,10 @@ ifdef CONFIG_DEBUG_SECTION_MISMATCH KBUILD_CFLAGS += -fno-inline-functions-called-once endif +# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0). ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections +KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y LDFLAGS_vmlinux += --gc-sections endif @@ -1026,10 +1106,11 @@ include $(addprefix $(srctree)/, $(include-y)) # Do not add $(call cc-option,...) below this line. When you build the kernel # from the clean source tree, the GCC plugins do not exist at this point. -# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments +# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments KBUILD_CPPFLAGS += $(KCPPFLAGS) KBUILD_AFLAGS += $(KAFLAGS) KBUILD_CFLAGS += $(KCFLAGS) +KBUILD_RUSTFLAGS += $(KRUSTFLAGS) KBUILD_LDFLAGS_MODULE += --build-id=sha1 LDFLAGS_vmlinux += --build-id=sha1 @@ -1104,6 +1185,7 @@ ifeq ($(KBUILD_EXTMOD),) core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ core-$(CONFIG_BLOCK) += block/ core-$(CONFIG_IO_URING) += io_uring/ +core-$(CONFIG_RUST) += rust/ vmlinux-dirs := $(patsubst %/,%,$(filter %/, \ $(core-y) $(core-m) $(drivers-y) $(drivers-m) \ @@ -1206,6 +1288,10 @@ prepare0: archprepare # All the preparing.. prepare: prepare0 +ifdef CONFIG_RUST + $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v + $(Q)$(MAKE) $(build)=rust +endif PHONY += remove-stale-files remove-stale-files: @@ -1499,7 +1585,7 @@ endif # CONFIG_MODULES # Directories & files removed with 'make clean' CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \ modules.builtin modules.builtin.modinfo modules.nsdeps \ - compile_commands.json .thinlto-cache + compile_commands.json .thinlto-cache rust/test rust/doc # Directories & files removed with 'make mrproper' MRPROPER_FILES += include/config include/generated \ @@ -1510,7 +1596,8 @@ MRPROPER_FILES += include/config include/generated \ certs/signing_key.pem \ certs/x509.genkey \ vmlinux-gdb.py \ - *.spec + *.spec \ + rust/target.json rust/libmacros.so # clean - Delete most, but leave enough to build external modules # @@ -1535,6 +1622,9 @@ $(mrproper-dirs): mrproper: clean $(mrproper-dirs) $(call cmd,rmfiles) + @find . $(RCS_FIND_IGNORE) \ + \( -name '*.rmeta' \) \ + -type f -print | xargs rm -f # distclean # @@ -1622,6 +1712,24 @@ help: @echo ' kselftest-merge - Merge all the config dependencies of' @echo ' kselftest to existing .config.' @echo '' + @echo 'Rust targets:' + @echo ' rustavailable - Checks whether the Rust toolchain is' + @echo ' available and, if not, explains why.' + @echo ' rustfmt - Reformat all the Rust code in the kernel' + @echo ' rustfmtcheck - Checks if all the Rust code in the kernel' + @echo ' is formatted, printing a diff otherwise.' + @echo ' rustdoc - Generate Rust documentation' + @echo ' (requires kernel .config)' + @echo ' rusttest - Runs the Rust tests' + @echo ' (requires kernel .config; downloads external repos)' + @echo ' rust-analyzer - Generate rust-project.json rust-analyzer support file' + @echo ' (requires kernel .config)' + @echo ' dir/file.[os] - Build specified target only' + @echo ' dir/file.rsi - Build macro expanded source, similar to C preprocessing.' + @echo ' Run with RUSTFMT=n to skip reformatting if needed.' + @echo ' The output is not intended to be compilable.' + @echo ' dir/file.ll - Build the LLVM assembly file' + @echo '' @$(if $(dtstree), \ echo 'Devicetree:'; \ echo '* dtbs - Build device tree blobs for enabled boards'; \ @@ -1694,6 +1802,52 @@ PHONY += $(DOC_TARGETS) $(DOC_TARGETS): $(Q)$(MAKE) $(build)=Documentation $@ + +# Rust targets +# --------------------------------------------------------------------------- + +# "Is Rust available?" target +PHONY += rustavailable +rustavailable: + $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v && echo "Rust is available!" + +# Documentation target +# +# Using the singular to avoid running afoul of `no-dot-config-targets`. +PHONY += rustdoc +rustdoc: prepare + $(Q)$(MAKE) $(build)=rust $@ + +# Testing target +PHONY += rusttest +rusttest: prepare + $(Q)$(MAKE) $(build)=rust $@ + +# Formatting targets +PHONY += rustfmt rustfmtcheck + +# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream. +# +# We match using absolute paths since `find` does not resolve them +# when matching, which is a problem when e.g. `srctree` is `..`. +# We `grep` afterwards in order to remove the directory entry itself. +rustfmt: + $(Q)find $(abs_srctree) -type f -name '*.rs' \ + -o -path $(abs_srctree)/rust/alloc -prune \ + -o -path $(abs_objtree)/rust/test -prune \ + | grep -Fv $(abs_srctree)/rust/alloc \ + | grep -Fv $(abs_objtree)/rust/test \ + | grep -Fv generated \ + | xargs $(RUSTFMT) $(rustfmt_flags) + +rustfmtcheck: rustfmt_flags = --check +rustfmtcheck: rustfmt + +# IDE support targets +PHONY += rust-analyzer +rust-analyzer: + $(Q)$(MAKE) $(build)=rust $@ + # Misc # --------------------------------------------------------------------------- @@ -1861,7 +2015,7 @@ $(clean-dirs): clean: $(clean-dirs) $(call cmd,rmfiles) @find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \ - \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \ + \( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \ -o -name '*.ko.*' \ -o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \ -o -name '*.dwo' -o -name '*.lst' \ diff --git a/arch/Kconfig b/arch/Kconfig index 8b311e400ec1..d9b4ae0fc805 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -355,6 +355,12 @@ config HAVE_RSEQ This symbol should be selected by an architecture if it supports an implementation of restartable sequences. +config HAVE_RUST + bool + help + This symbol should be selected by an architecture if it + supports Rust. + config HAVE_FUNCTION_ARG_ACCESS_API bool help diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h index 4f2a819fd60a..50b3f6b9502e 100644 --- a/include/linux/compiler_types.h +++ b/include/linux/compiler_types.h @@ -4,8 +4,12 @@ #ifndef __ASSEMBLY__ +/* + * Skipped when running bindgen due to a libclang issue; + * see https://github.com/rust-lang/rust-bindgen/issues/2244. + */ #if defined(CONFIG_DEBUG_INFO_BTF) && defined(CONFIG_PAHOLE_HAS_BTF_TAG) && \ - __has_attribute(btf_type_tag) + __has_attribute(btf_type_tag) && !defined(__BINDGEN__) # define BTF_TYPE_TAG(value) __attribute__((btf_type_tag(#value))) #else # define BTF_TYPE_TAG(value) /* nothing */ diff --git a/init/Kconfig b/init/Kconfig index 532362fcfe31..a078cb026523 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -60,6 +60,17 @@ config LLD_VERSION default $(ld-version) if LD_IS_LLD default 0 +config RUST_IS_AVAILABLE + def_bool $(success,$(srctree)/scripts/rust_is_available.sh) + help + This shows whether a suitable Rust toolchain is available (found). + + Please see Documentation/rust/quick-start.rst for instructions on how + to satify the build requirements of Rust support. + + In particular, the Makefile target 'rustavailable' is useful to check + why the Rust toolchain is not being detected. + config CC_CAN_LINK bool default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(CLANG_FLAGS) $(USERCFLAGS) $(USERLDFLAGS) $(m64-flag)) if 64BIT @@ -147,7 +158,8 @@ config WERROR default COMPILE_TEST help A kernel build should not cause any compiler warnings, and this - enables the '-Werror' flag to enforce that rule by default. + enables the '-Werror' (for C) and '-Dwarnings' (for Rust) flags + to enforce that rule by default. However, if you have a new (or very old) compiler with odd and unusual warnings, or you have some architecture with problems, @@ -1899,6 +1911,38 @@ config PROFILING Say Y here to enable the extended profiling support mechanisms used by profilers. +config RUST + bool "Rust support" + depends on HAVE_RUST + depends on RUST_IS_AVAILABLE + depends on !MODVERSIONS + depends on !GCC_PLUGINS + depends on !RANDSTRUCT + depends on !DEBUG_INFO_BTF + select CONSTRUCTORS + help + Enables Rust support in the kernel. + + This allows other Rust-related options, like drivers written in Rust, + to be selected. + + It is also required to be able to load external kernel modules + written in Rust. + + See Documentation/rust/ for more information. + + If unsure, say N. + +config RUSTC_VERSION_TEXT + string + depends on RUST + default $(shell,command -v $(RUSTC) >/dev/null 2>&1 && $(RUSTC) --version || echo n) + +config BINDGEN_VERSION_TEXT + string + depends on RUST + default $(shell,command -v $(BINDGEN) >/dev/null 2>&1 && $(BINDGEN) --version || echo n) + # # Place an empty function call at each tracepoint site. Can be # dynamically changed for a probe function. diff --git a/kernel/configs/rust.config b/kernel/configs/rust.config new file mode 100644 index 000000000000..38a7c5362c9c --- /dev/null +++ b/kernel/configs/rust.config @@ -0,0 +1 @@ +CONFIG_RUST=y diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index d3e5f36bb01e..e62271da937f 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -2710,6 +2710,40 @@ config HYPERV_TESTING endmenu # "Kernel Testing and Coverage" +menu "Rust hacking" + +config RUST_DEBUG_ASSERTIONS + bool "Debug assertions" + depends on RUST + help + Enables rustc's `-Cdebug-assertions` codegen option. + + This flag lets you turn `cfg(debug_assertions)` conditional + compilation on or off. This can be used to enable extra debugging + code in development but not in production. For example, it controls + the behavior of the standard library's `debug_assert!` macro. + + Note that this will apply to all Rust code, including `core`. + + If unsure, say N. + +config RUST_OVERFLOW_CHECKS + bool "Overflow checks" + default y + depends on RUST + help + Enables rustc's `-Coverflow-checks` codegen option. + + This flag allows you to control the behavior of runtime integer + overflow. When overflow-checks are enabled, a Rust panic will occur + on overflow. + + Note that this will apply to all Rust code, including `core`. + + If unsure, say Y. + +endmenu # "Rust" + source "Documentation/Kconfig" endmenu # Kernel hacking diff --git a/rust/.gitignore b/rust/.gitignore new file mode 100644 index 000000000000..9bd1af8e05a1 --- /dev/null +++ b/rust/.gitignore @@ -0,0 +1,8 @@ +# SPDX-License-Identifier: GPL-2.0 + +target.json +bindings_generated.rs +bindings_helpers_generated.rs +exports_*_generated.h +doc/ +test/ diff --git a/rust/Makefile b/rust/Makefile new file mode 100644 index 000000000000..7700d3853404 --- /dev/null +++ b/rust/Makefile @@ -0,0 +1,381 @@ +# SPDX-License-Identifier: GPL-2.0 + +always-$(CONFIG_RUST) += target.json +no-clean-files += target.json + +obj-$(CONFIG_RUST) += core.o compiler_builtins.o +always-$(CONFIG_RUST) += exports_core_generated.h + +# Missing prototypes are expected in the helpers since these are exported +# for Rust only, thus there is no header nor prototypes. +obj-$(CONFIG_RUST) += helpers.o +CFLAGS_REMOVE_helpers.o = -Wmissing-prototypes -Wmissing-declarations + +always-$(CONFIG_RUST) += libmacros.so +no-clean-files += libmacros.so + +always-$(CONFIG_RUST) += bindings/bindings_generated.rs bindings/bindings_helpers_generated.rs +obj-$(CONFIG_RUST) += alloc.o bindings.o kernel.o +always-$(CONFIG_RUST) += exports_alloc_generated.h exports_bindings_generated.h \ + exports_kernel_generated.h + +obj-$(CONFIG_RUST) += exports.o + +# Avoids running `$(RUSTC)` for the sysroot when it may not be available. +ifdef CONFIG_RUST + +# `$(rust_flags)` is passed in case the user added `--sysroot`. +rustc_sysroot := $(shell $(RUSTC) $(rust_flags) --print sysroot) +rustc_host_target := $(shell $(RUSTC) --version --verbose | grep -F 'host: ' | cut -d' ' -f2) +RUST_LIB_SRC ?= $(rustc_sysroot)/lib/rustlib/src/rust/library + +ifeq ($(quiet),silent_) +cargo_quiet=-q +rust_test_quiet=-q +rustdoc_test_quiet=--test-args -q +else ifeq ($(quiet),quiet_) +rust_test_quiet=-q +rustdoc_test_quiet=--test-args -q +else +cargo_quiet=--verbose +endif + +core-cfgs = \ + --cfg no_fp_fmt_parse + +alloc-cfgs = \ + --cfg no_fmt \ + --cfg no_global_oom_handling \ + --cfg no_macros \ + --cfg no_rc \ + --cfg no_str \ + --cfg no_string \ + --cfg no_sync \ + --cfg no_thin + +quiet_cmd_rustdoc = RUSTDOC $(if $(rustdoc_host),H, ) $< + cmd_rustdoc = \ + OBJTREE=$(abspath $(objtree)) \ + $(RUSTDOC) $(if $(rustdoc_host),$(rust_common_flags),$(rust_flags)) \ + $(rustc_target_flags) -L$(objtree)/$(obj) \ + --output $(objtree)/$(obj)/doc \ + --crate-name $(subst rustdoc-,,$@) \ + @$(objtree)/include/generated/rustc_cfg $< + +# The `html_logo_url` and `html_favicon_url` forms of the `doc` attribute +# can be used to specify a custom logo. However: +# - The given value is used as-is, thus it cannot be relative or a local file +# (unlike the non-custom case) since the generated docs have subfolders. +# - It requires adding it to every crate. +# - It requires changing `core` which comes from the sysroot. +# +# Using `-Zcrate-attr` would solve the last two points, but not the first. +# The https://github.com/rust-lang/rfcs/pull/3226 RFC suggests two new +# command-like flags to solve the issue. Meanwhile, we use the non-custom case +# and then retouch the generated files. +rustdoc: rustdoc-core rustdoc-macros rustdoc-compiler_builtins \ + rustdoc-alloc rustdoc-kernel + $(Q)cp $(srctree)/Documentation/images/logo.svg $(objtree)/$(obj)/doc + $(Q)cp $(srctree)/Documentation/images/COPYING-logo $(objtree)/$(obj)/doc + $(Q)find $(objtree)/$(obj)/doc -name '*.html' -type f -print0 | xargs -0 sed -Ei \ + -e 's:rust-logo\.svg:logo.svg:g' \ + -e 's:rust-logo\.png:logo.svg:g' \ + -e 's:favicon\.svg:logo.svg:g' \ + -e 's:::g' + $(Q)echo '.logo-container > img { object-fit: contain; }' \ + >> $(objtree)/$(obj)/doc/rustdoc.css + +rustdoc-macros: private rustdoc_host = yes +rustdoc-macros: private rustc_target_flags = --crate-type proc-macro \ + --extern proc_macro +rustdoc-macros: $(src)/macros/lib.rs FORCE + $(call if_changed,rustdoc) + +rustdoc-core: private rustc_target_flags = $(core-cfgs) +rustdoc-core: $(RUST_LIB_SRC)/core/src/lib.rs FORCE + $(call if_changed,rustdoc) + +rustdoc-compiler_builtins: $(src)/compiler_builtins.rs rustdoc-core FORCE + $(call if_changed,rustdoc) + +# We need to allow `rustdoc::broken_intra_doc_links` because some +# `no_global_oom_handling` functions refer to non-`no_global_oom_handling` +# functions. Ideally `rustdoc` would have a way to distinguish broken links +# due to things that are "configured out" vs. entirely non-existing ones. +rustdoc-alloc: private rustc_target_flags = $(alloc-cfgs) \ + -Arustdoc::broken_intra_doc_links +rustdoc-alloc: $(src)/alloc/lib.rs rustdoc-core rustdoc-compiler_builtins FORCE + $(call if_changed,rustdoc) + +rustdoc-kernel: private rustc_target_flags = --extern alloc \ + --extern macros=$(objtree)/$(obj)/libmacros.so \ + --extern bindings +rustdoc-kernel: $(src)/kernel/lib.rs rustdoc-core rustdoc-macros \ + rustdoc-compiler_builtins rustdoc-alloc $(obj)/libmacros.so \ + $(obj)/bindings.o FORCE + $(call if_changed,rustdoc) + +quiet_cmd_rustc_test_library = RUSTC TL $< + cmd_rustc_test_library = \ + OBJTREE=$(abspath $(objtree)) \ + $(RUSTC) $(rust_common_flags) \ + @$(objtree)/include/generated/rustc_cfg $(rustc_target_flags) \ + --crate-type $(if $(rustc_test_library_proc),proc-macro,rlib) \ + --out-dir $(objtree)/$(obj)/test --cfg testlib \ + --sysroot $(objtree)/$(obj)/test/sysroot \ + -L$(objtree)/$(obj)/test \ + --crate-name $(subst rusttest-,,$(subst rusttestlib-,,$@)) $< + +rusttestlib-macros: private rustc_target_flags = --extern proc_macro +rusttestlib-macros: private rustc_test_library_proc = yes +rusttestlib-macros: $(src)/macros/lib.rs rusttest-prepare FORCE + $(call if_changed,rustc_test_library) + +rusttestlib-bindings: $(src)/bindings/lib.rs rusttest-prepare FORCE + $(call if_changed,rustc_test_library) + +quiet_cmd_rustdoc_test = RUSTDOC T $< + cmd_rustdoc_test = \ + OBJTREE=$(abspath $(objtree)) \ + $(RUSTDOC) --test $(rust_common_flags) \ + @$(objtree)/include/generated/rustc_cfg \ + $(rustc_target_flags) $(rustdoc_test_target_flags) \ + --sysroot $(objtree)/$(obj)/test/sysroot $(rustdoc_test_quiet) \ + -L$(objtree)/$(obj)/test --output $(objtree)/$(obj)/doc \ + --crate-name $(subst rusttest-,,$@) $< + +# We cannot use `-Zpanic-abort-tests` because some tests are dynamic, +# so for the moment we skip `-Cpanic=abort`. +quiet_cmd_rustc_test = RUSTC T $< + cmd_rustc_test = \ + OBJTREE=$(abspath $(objtree)) \ + $(RUSTC) --test $(rust_common_flags) \ + @$(objtree)/include/generated/rustc_cfg \ + $(rustc_target_flags) --out-dir $(objtree)/$(obj)/test \ + --sysroot $(objtree)/$(obj)/test/sysroot \ + -L$(objtree)/$(obj)/test \ + --crate-name $(subst rusttest-,,$@) $<; \ + $(objtree)/$(obj)/test/$(subst rusttest-,,$@) $(rust_test_quiet) \ + $(rustc_test_run_flags) + +rusttest: rusttest-macros rusttest-kernel + +# This prepares a custom sysroot with our custom `alloc` instead of +# the standard one. +# +# This requires several hacks: +# - Unlike `core` and `alloc`, `std` depends on more than a dozen crates, +# including third-party crates that need to be downloaded, plus custom +# `build.rs` steps. Thus hardcoding things here is not maintainable. +# - `cargo` knows how to build the standard library, but it is an unstable +# feature so far (`-Zbuild-std`). +# - `cargo` only considers the use case of building the standard library +# to use it in a given package. Thus we need to create a dummy package +# and pick the generated libraries from there. +# - Since we only keep a subset of upstream `alloc` in-tree, we need +# to recreate it on the fly by putting our sources on top. +# - The usual ways of modifying the dependency graph in `cargo` do not seem +# to apply for the `-Zbuild-std` steps, thus we have to mislead it +# by modifying the sources in the sysroot. +# - To avoid messing with the user's Rust installation, we create a clone +# of the sysroot. However, `cargo` ignores `RUSTFLAGS` in the `-Zbuild-std` +# steps, thus we use a wrapper binary passed via `RUSTC` to pass the flag. +# +# In the future, we hope to avoid the whole ordeal by either: +# - Making the `test` crate not depend on `std` (either improving upstream +# or having our own custom crate). +# - Making the tests run in kernel space (requires the previous point). +# - Making `std` and friends be more like a "normal" crate, so that +# `-Zbuild-std` and related hacks are not needed. +quiet_cmd_rustsysroot = RUSTSYSROOT + cmd_rustsysroot = \ + rm -rf $(objtree)/$(obj)/test; \ + mkdir -p $(objtree)/$(obj)/test; \ + cp -a $(rustc_sysroot) $(objtree)/$(obj)/test/sysroot; \ + cp -r $(srctree)/$(src)/alloc/* \ + $(objtree)/$(obj)/test/sysroot/lib/rustlib/src/rust/library/alloc/src; \ + echo '\#!/bin/sh' > $(objtree)/$(obj)/test/rustc_sysroot; \ + echo "$(RUSTC) --sysroot=$(abspath $(objtree)/$(obj)/test/sysroot) \"\$$@\"" \ + >> $(objtree)/$(obj)/test/rustc_sysroot; \ + chmod u+x $(objtree)/$(obj)/test/rustc_sysroot; \ + $(CARGO) -q new $(objtree)/$(obj)/test/dummy; \ + RUSTC=$(objtree)/$(obj)/test/rustc_sysroot $(CARGO) $(cargo_quiet) \ + test -Zbuild-std --target $(rustc_host_target) \ + --manifest-path $(objtree)/$(obj)/test/dummy/Cargo.toml; \ + rm $(objtree)/$(obj)/test/sysroot/lib/rustlib/$(rustc_host_target)/lib/*; \ + cp $(objtree)/$(obj)/test/dummy/target/$(rustc_host_target)/debug/deps/* \ + $(objtree)/$(obj)/test/sysroot/lib/rustlib/$(rustc_host_target)/lib + +rusttest-prepare: FORCE + $(call if_changed,rustsysroot) + +rusttest-macros: private rustc_target_flags = --extern proc_macro +rusttest-macros: private rustdoc_test_target_flags = --crate-type proc-macro +rusttest-macros: $(src)/macros/lib.rs rusttest-prepare FORCE + $(call if_changed,rustc_test) + $(call if_changed,rustdoc_test) + +rusttest-kernel: private rustc_target_flags = --extern alloc \ + --extern macros --extern bindings +rusttest-kernel: $(src)/kernel/lib.rs rusttest-prepare \ + rusttestlib-macros rusttestlib-bindings FORCE + $(call if_changed,rustc_test) + $(call if_changed,rustc_test_library) + +filechk_rust_target = $(objtree)/scripts/generate_rust_target < $< + +$(obj)/target.json: $(objtree)/include/config/auto.conf FORCE + $(call filechk,rust_target) + +ifdef CONFIG_CC_IS_CLANG +bindgen_c_flags = $(c_flags) +else +# bindgen relies on libclang to parse C. Ideally, bindgen would support a GCC +# plugin backend and/or the Clang driver would be perfectly compatible with GCC. +# +# For the moment, here we are tweaking the flags on the fly. This is a hack, +# and some kernel configurations may not work (e.g. `GCC_PLUGIN_RANDSTRUCT` +# if we end up using one of those structs). +bindgen_skip_c_flags := -mno-fp-ret-in-387 -mpreferred-stack-boundary=% \ + -mskip-rax-setup -mgeneral-regs-only -msign-return-address=% \ + -mindirect-branch=thunk-extern -mindirect-branch-register \ + -mfunction-return=thunk-extern -mrecord-mcount -mabi=lp64 \ + -mindirect-branch-cs-prefix -mstack-protector-guard% -mtraceback=no \ + -mno-pointers-to-nested-functions -mno-string \ + -mno-strict-align -mstrict-align \ + -fconserve-stack -falign-jumps=% -falign-loops=% \ + -femit-struct-debug-baseonly -fno-ipa-cp-clone -fno-ipa-sra \ + -fno-partial-inlining -fplugin-arg-arm_ssp_per_task_plugin-% \ + -fno-reorder-blocks -fno-allow-store-data-races -fasan-shadow-offset=% \ + -fzero-call-used-regs=% -fno-stack-clash-protection \ + -fno-inline-functions-called-once \ + --param=% --param asan-% + +# Derived from `scripts/Makefile.clang`. +BINDGEN_TARGET_x86 := x86_64-linux-gnu +BINDGEN_TARGET := $(BINDGEN_TARGET_$(SRCARCH)) + +# All warnings are inhibited since GCC builds are very experimental, +# many GCC warnings are not supported by Clang, they may only appear in +# some configurations, with new GCC versions, etc. +bindgen_extra_c_flags = -w --target=$(BINDGEN_TARGET) + +bindgen_c_flags = $(filter-out $(bindgen_skip_c_flags), $(c_flags)) \ + $(bindgen_extra_c_flags) +endif + +ifdef CONFIG_LTO +bindgen_c_flags_lto = $(filter-out $(CC_FLAGS_LTO), $(bindgen_c_flags)) +else +bindgen_c_flags_lto = $(bindgen_c_flags) +endif + +bindgen_c_flags_final = $(bindgen_c_flags_lto) -D__BINDGEN__ + +quiet_cmd_bindgen = BINDGEN $@ + cmd_bindgen = \ + $(BINDGEN) $< $(bindgen_target_flags) \ + --use-core --with-derive-default --ctypes-prefix core::ffi --no-layout-tests \ + --no-debug '.*' \ + --size_t-is-usize -o $@ -- $(bindgen_c_flags_final) -DMODULE \ + $(bindgen_target_cflags) $(bindgen_target_extra) + +$(obj)/bindings/bindings_generated.rs: private bindgen_target_flags = \ + $(shell grep -v '^\#\|^$$' $(srctree)/$(src)/bindgen_parameters) +$(obj)/bindings/bindings_generated.rs: $(src)/bindings/bindings_helper.h \ + $(src)/bindgen_parameters FORCE + $(call if_changed_dep,bindgen) + +# See `CFLAGS_REMOVE_helpers.o` above. In addition, Clang on C does not warn +# with `-Wmissing-declarations` (unlike GCC), so it is not strictly needed here +# given it is `libclang`; but for consistency, future Clang changes and/or +# a potential future GCC backend for `bindgen`, we disable it too. +$(obj)/bindings/bindings_helpers_generated.rs: private bindgen_target_flags = \ + --blacklist-type '.*' --whitelist-var '' \ + --whitelist-function 'rust_helper_.*' +$(obj)/bindings/bindings_helpers_generated.rs: private bindgen_target_cflags = \ + -I$(objtree)/$(obj) -Wno-missing-prototypes -Wno-missing-declarations +$(obj)/bindings/bindings_helpers_generated.rs: private bindgen_target_extra = ; \ + sed -Ei 's/pub fn rust_helper_([a-zA-Z0-9_]*)/#[link_name="rust_helper_\1"]\n pub fn \1/g' $@ +$(obj)/bindings/bindings_helpers_generated.rs: $(src)/helpers.c FORCE + $(call if_changed_dep,bindgen) + +quiet_cmd_exports = EXPORTS $@ + cmd_exports = \ + $(NM) -p --defined-only $< \ + | grep -E ' (T|R|D) ' | cut -d ' ' -f 3 \ + | xargs -Isymbol \ + echo 'EXPORT_SYMBOL_RUST_GPL(symbol);' > $@ + +$(obj)/exports_core_generated.h: $(obj)/core.o FORCE + $(call if_changed,exports) + +$(obj)/exports_alloc_generated.h: $(obj)/alloc.o FORCE + $(call if_changed,exports) + +$(obj)/exports_bindings_generated.h: $(obj)/bindings.o FORCE + $(call if_changed,exports) + +$(obj)/exports_kernel_generated.h: $(obj)/kernel.o FORCE + $(call if_changed,exports) + +quiet_cmd_rustc_procmacro = $(RUSTC_OR_CLIPPY_QUIET) P $@ + cmd_rustc_procmacro = \ + $(RUSTC_OR_CLIPPY) $(rust_common_flags) \ + --emit=dep-info,link --extern proc_macro \ + --crate-type proc-macro --out-dir $(objtree)/$(obj) \ + --crate-name $(patsubst lib%.so,%,$(notdir $@)) $<; \ + mv $(objtree)/$(obj)/$(patsubst lib%.so,%,$(notdir $@)).d $(depfile); \ + sed -i '/^\#/d' $(depfile) + +# Procedural macros can only be used with the `rustc` that compiled it. +# Therefore, to get `libmacros.so` automatically recompiled when the compiler +# version changes, we add `core.o` as a dependency (even if it is not needed). +$(obj)/libmacros.so: $(src)/macros/lib.rs $(obj)/core.o FORCE + $(call if_changed_dep,rustc_procmacro) + +quiet_cmd_rustc_library = $(if $(skip_clippy),RUSTC,$(RUSTC_OR_CLIPPY_QUIET)) L $@ + cmd_rustc_library = \ + OBJTREE=$(abspath $(objtree)) \ + $(if $(skip_clippy),$(RUSTC),$(RUSTC_OR_CLIPPY)) \ + $(filter-out $(skip_flags),$(rust_flags) $(rustc_target_flags)) \ + --emit=dep-info,obj,metadata --crate-type rlib \ + --out-dir $(objtree)/$(obj) -L$(objtree)/$(obj) \ + --crate-name $(patsubst %.o,%,$(notdir $@)) $<; \ + mv $(objtree)/$(obj)/$(patsubst %.o,%,$(notdir $@)).d $(depfile); \ + sed -i '/^\#/d' $(depfile) \ + $(if $(rustc_objcopy),;$(OBJCOPY) $(rustc_objcopy) $@) + +rust-analyzer: + $(Q)$(srctree)/scripts/generate_rust_analyzer.py $(srctree) $(objtree) \ + $(RUST_LIB_SRC) > $(objtree)/rust-project.json + +$(obj)/core.o: private skip_clippy = 1 +$(obj)/core.o: private skip_flags = -Dunreachable_pub +$(obj)/core.o: private rustc_target_flags = $(core-cfgs) +$(obj)/core.o: $(RUST_LIB_SRC)/core/src/lib.rs $(obj)/target.json FORCE + $(call if_changed_dep,rustc_library) + +$(obj)/compiler_builtins.o: private rustc_objcopy = -w -W '__*' +$(obj)/compiler_builtins.o: $(src)/compiler_builtins.rs $(obj)/core.o FORCE + $(call if_changed_dep,rustc_library) + +$(obj)/alloc.o: private skip_clippy = 1 +$(obj)/alloc.o: private skip_flags = -Dunreachable_pub +$(obj)/alloc.o: private rustc_target_flags = $(alloc-cfgs) +$(obj)/alloc.o: $(src)/alloc/lib.rs $(obj)/compiler_builtins.o FORCE + $(call if_changed_dep,rustc_library) + +$(obj)/bindings.o: $(src)/bindings/lib.rs \ + $(obj)/compiler_builtins.o \ + $(obj)/bindings/bindings_generated.rs \ + $(obj)/bindings/bindings_helpers_generated.rs FORCE + $(call if_changed_dep,rustc_library) + +$(obj)/kernel.o: private rustc_target_flags = --extern alloc \ + --extern macros --extern bindings +$(obj)/kernel.o: $(src)/kernel/lib.rs $(obj)/alloc.o \ + $(obj)/libmacros.so $(obj)/bindings.o FORCE + $(call if_changed_dep,rustc_library) + +endif # CONFIG_RUST diff --git a/rust/bindgen_parameters b/rust/bindgen_parameters new file mode 100644 index 000000000000..be4963bf7203 --- /dev/null +++ b/rust/bindgen_parameters @@ -0,0 +1,21 @@ +# SPDX-License-Identifier: GPL-2.0 + +--opaque-type xregs_state +--opaque-type desc_struct +--opaque-type arch_lbr_state +--opaque-type local_apic + +# Packed type cannot transitively contain a `#[repr(align)]` type. +--opaque-type x86_msi_data +--opaque-type x86_msi_addr_lo + +# `try` is a reserved keyword since Rust 2018; solved in `bindgen` v0.59.2, +# commit 2aed6b021680 ("context: Escape the try keyword properly"). +--opaque-type kunit_try_catch + +# If SMP is disabled, `arch_spinlock_t` is defined as a ZST which triggers a Rust +# warning. We don't need to peek into it anyway. +--opaque-type spinlock + +# `seccomp`'s comment gets understood as a doctest +--no-doc-comments diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include index a0ccceb22cf8..274125307ebd 100644 --- a/scripts/Kconfig.include +++ b/scripts/Kconfig.include @@ -36,12 +36,12 @@ ld-option = $(success,$(LD) -v $(1)) as-instr = $(success,printf "%b\n" "$(1)" | $(CC) $(CLANG_FLAGS) -c -x assembler -o /dev/null -) # check if $(CC) and $(LD) exist -$(error-if,$(failure,command -v $(CC)),compiler '$(CC)' not found) +$(error-if,$(failure,command -v $(CC)),C compiler '$(CC)' not found) $(error-if,$(failure,command -v $(LD)),linker '$(LD)' not found) -# Get the compiler name, version, and error out if it is not supported. +# Get the C compiler name, version, and error out if it is not supported. cc-info := $(shell,$(srctree)/scripts/cc-version.sh $(CC)) -$(error-if,$(success,test -z "$(cc-info)"),Sorry$(comma) this compiler is not supported.) +$(error-if,$(success,test -z "$(cc-info)"),Sorry$(comma) this C compiler is not supported.) cc-name := $(shell,set -- $(cc-info) && echo $1) cc-version := $(shell,set -- $(cc-info) && echo $2) diff --git a/scripts/Makefile b/scripts/Makefile index f084f08ed176..1575af84d557 100644 --- a/scripts/Makefile +++ b/scripts/Makefile @@ -10,6 +10,9 @@ hostprogs-always-$(CONFIG_BUILDTIME_TABLE_SORT) += sorttable hostprogs-always-$(CONFIG_ASN1) += asn1_compiler hostprogs-always-$(CONFIG_MODULE_SIG_FORMAT) += sign-file hostprogs-always-$(CONFIG_SYSTEM_EXTRA_CERTIFICATE) += insert-sys-cert +hostprogs-always-$(CONFIG_RUST) += generate_rust_target + +generate_rust_target-rust := y HOSTCFLAGS_sorttable.o = -I$(srctree)/tools/include HOSTLDLIBS_sorttable = -lpthread diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 784f46d41959..27be77c0d6d8 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -26,6 +26,7 @@ EXTRA_CPPFLAGS := EXTRA_LDFLAGS := asflags-y := ccflags-y := +rustflags-y := cppflags-y := ldflags-y := @@ -271,6 +272,65 @@ quiet_cmd_cc_lst_c = MKLST $@ $(obj)/%.lst: $(src)/%.c FORCE $(call if_changed_dep,cc_lst_c) +# Compile Rust sources (.rs) +# --------------------------------------------------------------------------- + +rust_allowed_features := core_ffi_c + +rust_common_cmd = \ + RUST_MODFILE=$(modfile) $(RUSTC_OR_CLIPPY) $(rust_flags) \ + -Zallow-features=$(rust_allowed_features) \ + -Zcrate-attr=no_std \ + -Zcrate-attr='feature($(rust_allowed_features))' \ + --extern alloc --extern kernel \ + --crate-type rlib --out-dir $(obj) -L $(objtree)/rust/ \ + --crate-name $(basename $(notdir $@)) + +rust_handle_depfile = \ + mv $(obj)/$(basename $(notdir $@)).d $(depfile); \ + sed -i '/^\#/d' $(depfile) + +# `--emit=obj`, `--emit=asm` and `--emit=llvm-ir` imply a single codegen unit +# will be used. We explicitly request `-Ccodegen-units=1` in any case, and +# the compiler shows a warning if it is not 1. However, if we ever stop +# requesting it explicitly and we start using some other `--emit` that does not +# imply it (and for which codegen is performed), then we would be out of sync, +# i.e. the outputs we would get for the different single targets (e.g. `.ll`) +# would not match each other. + +quiet_cmd_rustc_o_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@ + cmd_rustc_o_rs = \ + $(rust_common_cmd) --emit=dep-info,obj $<; \ + $(rust_handle_depfile) + +$(obj)/%.o: $(src)/%.rs FORCE + $(call if_changed_dep,rustc_o_rs) + +quiet_cmd_rustc_rsi_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@ + cmd_rustc_rsi_rs = \ + $(rust_common_cmd) --emit=dep-info -Zunpretty=expanded $< >$@; \ + command -v $(RUSTFMT) >/dev/null && $(RUSTFMT) $@; \ + $(rust_handle_depfile) + +$(obj)/%.rsi: $(src)/%.rs FORCE + $(call if_changed_dep,rustc_rsi_rs) + +quiet_cmd_rustc_s_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@ + cmd_rustc_s_rs = \ + $(rust_common_cmd) --emit=dep-info,asm $<; \ + $(rust_handle_depfile) + +$(obj)/%.s: $(src)/%.rs FORCE + $(call if_changed_dep,rustc_s_rs) + +quiet_cmd_rustc_ll_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@ + cmd_rustc_ll_rs = \ + $(rust_common_cmd) --emit=dep-info,llvm-ir $<; \ + $(rust_handle_depfile) + +$(obj)/%.ll: $(src)/%.rs FORCE + $(call if_changed_dep,rustc_ll_rs) + # Compile assembler sources (.S) # --------------------------------------------------------------------------- diff --git a/scripts/Makefile.debug b/scripts/Makefile.debug index 8cf1cb22dd93..332c486f705f 100644 --- a/scripts/Makefile.debug +++ b/scripts/Makefile.debug @@ -1,4 +1,6 @@ DEBUG_CFLAGS := +DEBUG_RUSTFLAGS := + debug-flags-y := -g ifdef CONFIG_DEBUG_INFO_SPLIT @@ -17,9 +19,12 @@ KBUILD_AFLAGS += $(debug-flags-y) ifdef CONFIG_DEBUG_INFO_REDUCED DEBUG_CFLAGS += -fno-var-tracking +DEBUG_RUSTFLAGS += -Cdebuginfo=1 ifdef CONFIG_CC_IS_GCC DEBUG_CFLAGS += -femit-struct-debug-baseonly endif +else +DEBUG_RUSTFLAGS += -Cdebuginfo=2 endif ifdef CONFIG_DEBUG_INFO_COMPRESSED @@ -30,3 +35,6 @@ endif KBUILD_CFLAGS += $(DEBUG_CFLAGS) export DEBUG_CFLAGS + +KBUILD_RUSTFLAGS += $(DEBUG_RUSTFLAGS) +export DEBUG_RUSTFLAGS diff --git a/scripts/Makefile.host b/scripts/Makefile.host index 278b4d6ac945..da133780b751 100644 --- a/scripts/Makefile.host +++ b/scripts/Makefile.host @@ -22,6 +22,8 @@ $(obj)/%.tab.c $(obj)/%.tab.h: $(src)/%.y FORCE # to preprocess a data file. # # Both C and C++ are supported, but preferred language is C for such utilities. +# Rust is also supported, but it may only be used in scenarios where a Rust +# toolchain is required to be available (e.g. when `CONFIG_RUST` is enabled). # # Sample syntax (see Documentation/kbuild/makefiles.rst for reference) # hostprogs := bin2hex @@ -37,15 +39,20 @@ $(obj)/%.tab.c $(obj)/%.tab.h: $(src)/%.y FORCE # qconf-objs := menu.o # Will compile qconf as a C++ program, and menu as a C program. # They are linked as C++ code to the executable qconf +# +# hostprogs := target +# target-rust := y +# Will compile `target` as a Rust program, using `target.rs` as the crate root. +# The crate may consist of several source files. # C code # Executables compiled from a single .c file host-csingle := $(foreach m,$(hostprogs), \ - $(if $($(m)-objs)$($(m)-cxxobjs),,$(m))) + $(if $($(m)-objs)$($(m)-cxxobjs)$($(m)-rust),,$(m))) # C executables linked based on several .o files host-cmulti := $(foreach m,$(hostprogs),\ - $(if $($(m)-cxxobjs),,$(if $($(m)-objs),$(m)))) + $(if $($(m)-cxxobjs)$($(m)-rust),,$(if $($(m)-objs),$(m)))) # Object (.o) files compiled from .c files host-cobjs := $(sort $(foreach m,$(hostprogs),$($(m)-objs))) @@ -58,11 +65,17 @@ host-cxxmulti := $(foreach m,$(hostprogs),$(if $($(m)-cxxobjs),$(m))) # C++ Object (.o) files compiled from .cc files host-cxxobjs := $(sort $(foreach m,$(host-cxxmulti),$($(m)-cxxobjs))) +# Rust code +# Executables compiled from a single Rust crate (which may consist of +# one or more .rs files) +host-rust := $(foreach m,$(hostprogs),$(if $($(m)-rust),$(m))) + host-csingle := $(addprefix $(obj)/,$(host-csingle)) host-cmulti := $(addprefix $(obj)/,$(host-cmulti)) host-cobjs := $(addprefix $(obj)/,$(host-cobjs)) host-cxxmulti := $(addprefix $(obj)/,$(host-cxxmulti)) host-cxxobjs := $(addprefix $(obj)/,$(host-cxxobjs)) +host-rust := $(addprefix $(obj)/,$(host-rust)) ##### # Handle options to gcc. Support building with separate output directory @@ -71,6 +84,8 @@ _hostc_flags = $(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS) \ $(HOSTCFLAGS_$(target-stem).o) _hostcxx_flags = $(KBUILD_HOSTCXXFLAGS) $(HOST_EXTRACXXFLAGS) \ $(HOSTCXXFLAGS_$(target-stem).o) +_hostrust_flags = $(KBUILD_HOSTRUSTFLAGS) $(HOST_EXTRARUSTFLAGS) \ + $(HOSTRUSTFLAGS_$(target-stem)) # $(objtree)/$(obj) for including generated headers from checkin source files ifeq ($(KBUILD_EXTMOD),) @@ -82,6 +97,7 @@ endif hostc_flags = -Wp,-MMD,$(depfile) $(_hostc_flags) hostcxx_flags = -Wp,-MMD,$(depfile) $(_hostcxx_flags) +hostrust_flags = $(_hostrust_flags) ##### # Compile programs on the host @@ -128,5 +144,17 @@ quiet_cmd_host-cxxobjs = HOSTCXX $@ $(host-cxxobjs): $(obj)/%.o: $(src)/%.cc FORCE $(call if_changed_dep,host-cxxobjs) +# Create executable from a single Rust crate (which may consist of +# one or more `.rs` files) +# host-rust -> Executable +quiet_cmd_host-rust = HOSTRUSTC $@ + cmd_host-rust = \ + $(HOSTRUSTC) $(hostrust_flags) --emit=dep-info,link \ + --out-dir=$(obj)/ $<; \ + mv $(obj)/$(target-stem).d $(depfile); \ + sed -i '/^\#/d' $(depfile) +$(host-rust): $(obj)/%: $(src)/%.rs FORCE + $(call if_changed_dep,host-rust) + targets += $(host-csingle) $(host-cmulti) $(host-cobjs) \ - $(host-cxxmulti) $(host-cxxobjs) + $(host-cxxmulti) $(host-cxxobjs) $(host-rust) diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 3fb6a99e78c4..c88b98b5dc44 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -8,6 +8,7 @@ ldflags-y += $(EXTRA_LDFLAGS) # flags that take effect in current and sub directories KBUILD_AFLAGS += $(subdir-asflags-y) KBUILD_CFLAGS += $(subdir-ccflags-y) +KBUILD_RUSTFLAGS += $(subdir-rustflags-y) # Figure out what we need to build from the various variables # =========================================================================== @@ -128,6 +129,10 @@ _c_flags = $(filter-out $(CFLAGS_REMOVE_$(target-stem).o), \ $(filter-out $(ccflags-remove-y), \ $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(ccflags-y)) \ $(CFLAGS_$(target-stem).o)) +_rust_flags = $(filter-out $(RUSTFLAGS_REMOVE_$(target-stem).o), \ + $(filter-out $(rustflags-remove-y), \ + $(KBUILD_RUSTFLAGS) $(rustflags-y)) \ + $(RUSTFLAGS_$(target-stem).o)) _a_flags = $(filter-out $(AFLAGS_REMOVE_$(target-stem).o), \ $(filter-out $(asflags-remove-y), \ $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(asflags-y)) \ @@ -202,6 +207,11 @@ modkern_cflags = \ $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \ $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL) $(modfile_flags)) +modkern_rustflags = \ + $(if $(part-of-module), \ + $(KBUILD_RUSTFLAGS_MODULE) $(RUSTFLAGS_MODULE), \ + $(KBUILD_RUSTFLAGS_KERNEL) $(RUSTFLAGS_KERNEL)) + modkern_aflags = $(if $(part-of-module), \ $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE), \ $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)) @@ -211,6 +221,8 @@ c_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ $(_c_flags) $(modkern_cflags) \ $(basename_flags) $(modname_flags) +rust_flags = $(_rust_flags) $(modkern_rustflags) @$(objtree)/include/generated/rustc_cfg + a_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ $(_a_flags) $(modkern_aflags) diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal index 35100e981f4a..9a1fa6aa30fe 100644 --- a/scripts/Makefile.modfinal +++ b/scripts/Makefile.modfinal @@ -39,11 +39,13 @@ quiet_cmd_ld_ko_o = LD [M] $@ quiet_cmd_btf_ko = BTF [M] $@ cmd_btf_ko = \ - if [ -f vmlinux ]; then \ + if [ ! -f vmlinux ]; then \ + printf "Skipping BTF generation for %s due to unavailability of vmlinux\n" $@ 1>&2; \ + elif [ -n "$(CONFIG_RUST)" ] && $(srctree)/scripts/is_rust_module.sh $@; then \ + printf "Skipping BTF generation for %s because it's a Rust module\n" $@ 1>&2; \ + else \ LLVM_OBJCOPY="$(OBJCOPY)" $(PAHOLE) -J $(PAHOLE_FLAGS) --btf_base vmlinux $@; \ $(RESOLVE_BTFIDS) -b vmlinux $@; \ - else \ - printf "Skipping BTF generation for %s due to unavailability of vmlinux\n" $@ 1>&2; \ fi; # Same as newer-prereqs, but allows to exclude specified extra dependencies diff --git a/scripts/cc-version.sh b/scripts/cc-version.sh index f1952c522466..2401c86fcf53 100755 --- a/scripts/cc-version.sh +++ b/scripts/cc-version.sh @@ -1,13 +1,13 @@ #!/bin/sh # SPDX-License-Identifier: GPL-2.0 # -# Print the compiler name and its version in a 5 or 6-digit form. +# Print the C compiler name and its version in a 5 or 6-digit form. # Also, perform the minimum version check. set -e -# Print the compiler name and some version components. -get_compiler_info() +# Print the C compiler name and some version components. +get_c_compiler_info() { cat <<- EOF | "$@" -E -P -x c - 2>/dev/null #if defined(__clang__) @@ -32,7 +32,7 @@ get_canonical_version() # $@ instead of $1 because multiple words might be given, e.g. CC="ccache gcc". orig_args="$@" -set -- $(get_compiler_info "$@") +set -- $(get_c_compiler_info "$@") name=$1 @@ -52,7 +52,7 @@ ICC) min_version=$($min_tool_version icc) ;; *) - echo "$orig_args: unknown compiler" >&2 + echo "$orig_args: unknown C compiler" >&2 exit 1 ;; esac @@ -62,7 +62,7 @@ min_cversion=$(get_canonical_version $min_version) if [ "$cversion" -lt "$min_cversion" ]; then echo >&2 "***" - echo >&2 "*** Compiler is too old." + echo >&2 "*** C compiler is too old." echo >&2 "*** Your $name version: $version" echo >&2 "*** Minimum $name version: $min_version" echo >&2 "***" diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c index c4340c90e172..b7c9f1dd5e42 100644 --- a/scripts/kconfig/confdata.c +++ b/scripts/kconfig/confdata.c @@ -216,6 +216,13 @@ static const char *conf_get_autoheader_name(void) return name ? name : "include/generated/autoconf.h"; } +static const char *conf_get_rustccfg_name(void) +{ + char *name = getenv("KCONFIG_RUSTCCFG"); + + return name ? name : "include/generated/rustc_cfg"; +} + static int conf_set_sym_val(struct symbol *sym, int def, int def_flags, char *p) { char *p2; @@ -605,6 +612,9 @@ static const struct comment_style comment_style_c = { static void conf_write_heading(FILE *fp, const struct comment_style *cs) { + if (!cs) + return; + fprintf(fp, "%s\n", cs->prefix); fprintf(fp, "%s Automatically generated file; DO NOT EDIT.\n", @@ -745,6 +755,65 @@ static void print_symbol_for_c(FILE *fp, struct symbol *sym) free(escaped); } +static void print_symbol_for_rustccfg(FILE *fp, struct symbol *sym) +{ + const char *val; + const char *val_prefix = ""; + char *val_prefixed = NULL; + size_t val_prefixed_len; + char *escaped = NULL; + + if (sym->type == S_UNKNOWN) + return; + + val = sym_get_string_value(sym); + + switch (sym->type) { + case S_BOOLEAN: + case S_TRISTATE: + /* + * We do not care about disabled ones, i.e. no need for + * what otherwise are "comments" in other printers. + */ + if (*val == 'n') + return; + + /* + * To have similar functionality to the C macro `IS_ENABLED()` + * we provide an empty `--cfg CONFIG_X` here in both `y` + * and `m` cases. + * + * Then, the common `fprintf()` below will also give us + * a `--cfg CONFIG_X="y"` or `--cfg CONFIG_X="m"`, which can + * be used as the equivalent of `IS_BUILTIN()`/`IS_MODULE()`. + */ + fprintf(fp, "--cfg=%s%s\n", CONFIG_, sym->name); + break; + case S_HEX: + if (val[0] != '0' || (val[1] != 'x' && val[1] != 'X')) + val_prefix = "0x"; + break; + default: + break; + } + + if (strlen(val_prefix) > 0) { + val_prefixed_len = strlen(val) + strlen(val_prefix) + 1; + val_prefixed = xmalloc(val_prefixed_len); + snprintf(val_prefixed, val_prefixed_len, "%s%s", val_prefix, val); + val = val_prefixed; + } + + /* All values get escaped: the `--cfg` option only takes strings */ + escaped = escape_string_value(val); + val = escaped; + + fprintf(fp, "--cfg=%s%s=%s\n", CONFIG_, sym->name, val); + + free(escaped); + free(val_prefixed); +} + /* * Write out a minimal config. * All values that has default values are skipped as this is redundant. @@ -1132,6 +1201,12 @@ int conf_write_autoconf(int overwrite) if (ret) return ret; + ret = __conf_write_autoconf(conf_get_rustccfg_name(), + print_symbol_for_rustccfg, + NULL); + if (ret) + return ret; + /* * Create include/config/auto.conf. This must be the last step because * Kbuild has a dependency on auto.conf and this marks the successful -- cgit v1.2.3-59-g8ed1b From 094981352ce27bc36018c009d07ddf974c9725f5 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Thu, 4 Aug 2022 12:16:44 +0200 Subject: x86: enable initial Rust support Note that only x86_64 is covered and not all features nor mitigations are handled, but it is enough as a starting point and showcases the basics needed to add Rust support for a new architecture. Reviewed-by: Kees Cook Reviewed-by: Greg Kroah-Hartman Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Co-developed-by: David Gow Signed-off-by: David Gow Signed-off-by: Miguel Ojeda --- Documentation/rust/arch-support.rst | 1 + arch/x86/Kconfig | 1 + arch/x86/Makefile | 10 ++++++++++ scripts/generate_rust_target.rs | 15 +++++++++++++-- 4 files changed, 25 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/Documentation/rust/arch-support.rst b/Documentation/rust/arch-support.rst index 1152e0fbdad0..6982b63775da 100644 --- a/Documentation/rust/arch-support.rst +++ b/Documentation/rust/arch-support.rst @@ -15,4 +15,5 @@ support corresponds to ``S`` values in the ``MAINTAINERS`` file. ============ ================ ============================================== Architecture Level of support Constraints ============ ================ ============================================== +``x86`` Maintained ``x86_64`` only. ============ ================ ============================================== diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index f9920f1341c8..3ca198742b10 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -257,6 +257,7 @@ config X86 select HAVE_STATIC_CALL_INLINE if HAVE_OBJTOOL select HAVE_PREEMPT_DYNAMIC_CALL select HAVE_RSEQ + select HAVE_RUST if X86_64 select HAVE_SYSCALL_TRACEPOINTS select HAVE_UACCESS_VALIDATION if HAVE_OBJTOOL select HAVE_UNSTABLE_SCHED_CLOCK diff --git a/arch/x86/Makefile b/arch/x86/Makefile index bafbd905e6e7..2d7e640674c6 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -68,6 +68,7 @@ export BITS # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53383 # KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow -mno-avx +KBUILD_RUSTFLAGS += -Ctarget-feature=-sse,-sse2,-sse3,-ssse3,-sse4.1,-sse4.2,-avx,-avx2 ifeq ($(CONFIG_X86_KERNEL_IBT),y) # @@ -155,8 +156,17 @@ else cflags-$(CONFIG_GENERIC_CPU) += -mtune=generic KBUILD_CFLAGS += $(cflags-y) + rustflags-$(CONFIG_MK8) += -Ctarget-cpu=k8 + rustflags-$(CONFIG_MPSC) += -Ctarget-cpu=nocona + rustflags-$(CONFIG_MCORE2) += -Ctarget-cpu=core2 + rustflags-$(CONFIG_MATOM) += -Ctarget-cpu=atom + rustflags-$(CONFIG_GENERIC_CPU) += -Ztune-cpu=generic + KBUILD_RUSTFLAGS += $(rustflags-y) + KBUILD_CFLAGS += -mno-red-zone KBUILD_CFLAGS += -mcmodel=kernel + KBUILD_RUSTFLAGS += -Cno-redzone=y + KBUILD_RUSTFLAGS += -Ccode-model=kernel endif # diff --git a/scripts/generate_rust_target.rs b/scripts/generate_rust_target.rs index 7256c9606cf0..3c6cbe2b278d 100644 --- a/scripts/generate_rust_target.rs +++ b/scripts/generate_rust_target.rs @@ -148,8 +148,19 @@ fn main() { let mut ts = TargetSpec::new(); // `llvm-target`s are taken from `scripts/Makefile.clang`. - if cfg.has("DUMMY_ARCH") { - ts.push("arch", "dummy_arch"); + if cfg.has("X86_64") { + ts.push("arch", "x86_64"); + ts.push( + "data-layout", + "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128", + ); + let mut features = "-3dnow,-3dnowa,-mmx,+soft-float".to_string(); + if cfg.has("RETPOLINE") { + features += ",+retpoline-external-thunk"; + } + ts.push("features", features); + ts.push("llvm-target", "x86_64-linux-gnu"); + ts.push("target-pointer-width", "64"); } else { panic!("Unsupported architecture"); } -- cgit v1.2.3-59-g8ed1b From a7f3257da8a86b96fb9bf1bba40ae0bbd7f1885a Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 7 Aug 2022 09:48:09 +0900 Subject: kbuild: remove the target in signal traps when interrupted When receiving some signal, GNU Make automatically deletes the target if it has already been changed by the interrupted recipe. If the target is possibly incomplete due to interruption, it must be deleted so that it will be remade from scratch on the next run of make. Otherwise, the target would remain corrupted permanently because its timestamp had already been updated. Thanks to this behavior of Make, you can stop the build any time by pressing Ctrl-C, and just run 'make' to resume it. Kbuild also relies on this feature, but it is equivalently important for any build systems that make decisions based on timestamps (if you want to support Ctrl-C reliably). However, this does not always work as claimed; Make immediately dies with Ctrl-C if its stderr goes into a pipe. [Test Makefile] foo: echo hello > $@ sleep 3 echo world >> $@ [Test Result] $ make # hit Ctrl-C echo hello > foo sleep 3 ^Cmake: *** Deleting file 'foo' make: *** [Makefile:3: foo] Interrupt $ make 2>&1 | cat # hit Ctrl-C echo hello > foo sleep 3 ^C$ # 'foo' is often left-over The reason is because SIGINT is sent to the entire process group. In this example, SIGINT kills 'cat', and 'make' writes the message to the closed pipe, then dies with SIGPIPE before cleaning the target. A typical bad scenario (as reported by [1], [2]) is to save build log by using the 'tee' command: $ make 2>&1 | tee log This can be problematic for any build systems based on Make, so I hope it will be fixed in GNU Make. The maintainer of GNU Make stated this is a long-standing issue and difficult to fix [3]. It has not been fixed yet as of writing. So, we cannot rely on Make cleaning the target. We can do it by ourselves, in signal traps. As far as I understand, Make takes care of SIGHUP, SIGINT, SIGQUIT, and SITERM for the target removal. I added the traps for them, and also for SIGPIPE just in case cmd_* rule prints something to stdout or stderr (but I did not observe an actual case where SIGPIPE was triggered). [Note 1] The trap handler might be worth explaining. rm -f $@; trap - $(sig); kill -s $(sig) $$ This lets the shell kill itself by the signal it caught, so the parent process can tell the child has exited on the signal. Generally, this is a proper manner for handling signals, in case the calling program (like Bash) may monitor WIFSIGNALED() and WTERMSIG() for WCE although this may not be a big deal here because GNU Make handles SIGHUP, SIGINT, SIGQUIT in WUE and SIGTERM in IUE. IUE - Immediate Unconditional Exit WUE - Wait and Unconditional Exit WCE - Wait and Cooperative Exit For details, see "Proper handling of SIGINT/SIGQUIT" [4]. [Note 2] Reverting 392885ee82d3 ("kbuild: let fixdep directly write to .*.cmd files") would directly address [1], but it only saves if_changed_dep. As reported in [2], all commands that use redirection can potentially leave an empty (i.e. broken) target. [Note 3] Another (even safer) approach might be to always write to a temporary file, and rename it to $@ at the end of the recipe. > $(tmp-target) mv $(tmp-target) $@ It would require a lot of Makefile changes, and result in ugly code, so I did not take it. [Note 4] A little more thoughts about a pattern rule with multiple targets (or a grouped target). %.x %.y: %.z When interrupted, GNU Make deletes both %.x and %.y, while this solution only deletes $@. Probably, this is not a big deal. The next run of make will execute the rule again to create $@ along with the other files. [1]: https://lore.kernel.org/all/YLeot94yAaM4xbMY@gmail.com/ [2]: https://lore.kernel.org/all/20220510221333.2770571-1-robh@kernel.org/ [3]: https://lists.gnu.org/archive/html/help-make/2021-06/msg00001.html [4]: https://www.cons.org/cracauer/sigint.html Fixes: 392885ee82d3 ("kbuild: let fixdep directly write to .*.cmd files") Reported-by: Ingo Molnar Reported-by: Rob Herring Signed-off-by: Masahiro Yamada Tested-by: Ingo Molnar Reviewed-by: Nicolas Schier --- scripts/Kbuild.include | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index ece44b735061..2bc08ace38a3 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -100,8 +100,29 @@ echo-cmd = $(if $($(quiet)cmd_$(1)),\ quiet_redirect := silent_redirect := exec >/dev/null; +# Delete the target on interruption +# +# GNU Make automatically deletes the target if it has already been changed by +# the interrupted recipe. So, you can safely stop the build by Ctrl-C (Make +# will delete incomplete targets), and resume it later. +# +# However, this does not work when the stderr is piped to another program, like +# $ make >&2 | tee log +# Make dies with SIGPIPE before cleaning the targets. +# +# To address it, we clean the target in signal traps. +# +# Make deletes the target when it catches SIGHUP, SIGINT, SIGQUIT, SIGTERM. +# So, we cover them, and also SIGPIPE just in case. +# +# Of course, this is unneeded for phony targets. +delete-on-interrupt = \ + $(if $(filter-out $(PHONY), $@), \ + $(foreach sig, HUP INT QUIT TERM PIPE, \ + trap 'rm -f $@; trap - $(sig); kill -s $(sig) $$$$' $(sig);)) + # printing commands -cmd = @set -e; $(echo-cmd) $($(quiet)redirect) $(cmd_$(1)) +cmd = @set -e; $(echo-cmd) $($(quiet)redirect) $(delete-on-interrupt) $(cmd_$(1)) ### # if_changed - execute command if any prerequisite is newer than -- cgit v1.2.3-59-g8ed1b From a3c4d4abaaf0b3fb3335a432fa9b75d414d1f987 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 25 Sep 2022 03:19:09 +0900 Subject: kbuild: hard-code KBUILD_ALLDIRS in scripts/Makefile.package My future plan is to list subdirectories in ./Kbuild. When it occurs, $(vmlinux-alldirs) will not contain all subdirectories. Let's hard-code the directory list until I get around to implementing a more sophisticated way for generating a source tarball. Signed-off-by: Masahiro Yamada Tested-by: Nick Desaulniers Reviewed-by: Nicolas Schier --- Makefile | 8 ++------ scripts/Makefile.package | 5 ++++- 2 files changed, 6 insertions(+), 7 deletions(-) (limited to 'scripts') diff --git a/Makefile b/Makefile index b87794a26d95..a42b121d1cd5 100644 --- a/Makefile +++ b/Makefile @@ -1109,13 +1109,11 @@ vmlinux-dirs := $(patsubst %/,%,$(filter %/, \ $(core-y) $(core-m) $(drivers-y) $(drivers-m) \ $(libs-y) $(libs-m))) -vmlinux-alldirs := $(sort $(vmlinux-dirs) Documentation \ +build-dirs := $(vmlinux-dirs) +clean-dirs := $(sort $(vmlinux-dirs) Documentation \ $(patsubst %/,%,$(filter %/, $(core-) \ $(drivers-) $(libs-)))) -build-dirs := $(vmlinux-dirs) -clean-dirs := $(vmlinux-alldirs) - subdir-modorder := $(addsuffix /modules.order, $(build-dirs)) # Externally visible symbols (used by link-vmlinux.sh) @@ -1131,8 +1129,6 @@ KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y)) export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds -# used by scripts/Makefile.package -export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools) vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS) diff --git a/scripts/Makefile.package b/scripts/Makefile.package index 5017f6b2da80..8bbcced67c22 100644 --- a/scripts/Makefile.package +++ b/scripts/Makefile.package @@ -29,7 +29,10 @@ KDEB_SOURCENAME ?= linux-upstream KBUILD_PKG_ROOTCMD ?="fakeroot -u" export KDEB_SOURCENAME # Include only those top-level files that are needed by make, plus the GPL copy -TAR_CONTENT := $(KBUILD_ALLDIRS) .config .scmversion Makefile \ +TAR_CONTENT := Documentation LICENSES arch block certs crypto drivers fs \ + include init io_uring ipc kernel lib mm net samples scripts \ + security sound tools usr virt \ + .config .scmversion Makefile \ Kbuild Kconfig COPYING $(wildcard localversion*) MKSPEC := $(srctree)/scripts/package/mkspec -- cgit v1.2.3-59-g8ed1b From b10fdeea8cf42c0d97b337e9e501c92da4389a03 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sat, 20 Aug 2022 18:15:29 +0900 Subject: kbuild: check sha1sum just once for each atomic header It is unneeded to check the sha1sum every time. Create the timestamp files to manage it. Add '.' to clean-dirs because 'make clean' must visit ./Kbuild to clean up the timestamp files. Signed-off-by: Masahiro Yamada --- Kbuild | 33 ++++++++++++++++++++++++--------- Makefile | 2 +- scripts/atomic/check-atomics.sh | 33 --------------------------------- 3 files changed, 25 insertions(+), 43 deletions(-) delete mode 100755 scripts/atomic/check-atomics.sh (limited to 'scripts') diff --git a/Kbuild b/Kbuild index e122d93cee32..0b9e8a16a621 100644 --- a/Kbuild +++ b/Kbuild @@ -43,17 +43,32 @@ PHONY += missing-syscalls missing-syscalls: scripts/checksyscalls.sh $(offsets-file) $(call cmd,syscalls) -# Check atomic headers are up-to-date - -quiet_cmd_atomics = CALL $< - cmd_atomics = $(CONFIG_SHELL) $< - -PHONY += old-atomics -old-atomics: scripts/atomic/check-atomics.sh - $(call cmd,atomics) +# Check the manual modification of atomic headers + +quiet_cmd_check_sha1 = CHKSHA1 $< + cmd_check_sha1 = \ + if ! command -v sha1sum >/dev/null; then \ + echo "warning: cannot check the header due to sha1sum missing"; \ + exit 0; \ + fi; \ + if [ "$$(sed -n '$$s:// ::p' $<)" != \ + "$$(sed '$$d' $< | sha1sum | sed 's/ .*//')" ]; then \ + echo "error: $< has been modified." >&2; \ + exit 1; \ + fi; \ + touch $@ + +atomic-checks += $(addprefix $(obj)/.checked-, \ + atomic-arch-fallback.h \ + atomic-instrumented.h \ + atomic-long.h) + +targets += $(atomic-checks) +$(atomic-checks): $(obj)/.checked-%: include/linux/atomic/% FORCE + $(call if_changed,check_sha1) # A phony target that depends on all the preparation targets PHONY += prepare -prepare: $(offsets-file) missing-syscalls old-atomics +prepare: $(offsets-file) missing-syscalls $(atomic-checks) @: diff --git a/Makefile b/Makefile index a42b121d1cd5..22a4afd51285 100644 --- a/Makefile +++ b/Makefile @@ -1110,7 +1110,7 @@ vmlinux-dirs := $(patsubst %/,%,$(filter %/, \ $(libs-y) $(libs-m))) build-dirs := $(vmlinux-dirs) -clean-dirs := $(sort $(vmlinux-dirs) Documentation \ +clean-dirs := $(sort $(vmlinux-dirs) Documentation . \ $(patsubst %/,%,$(filter %/, $(core-) \ $(drivers-) $(libs-)))) diff --git a/scripts/atomic/check-atomics.sh b/scripts/atomic/check-atomics.sh deleted file mode 100755 index 0e7bab3eb0d1..000000000000 --- a/scripts/atomic/check-atomics.sh +++ /dev/null @@ -1,33 +0,0 @@ -#!/bin/sh -# SPDX-License-Identifier: GPL-2.0 -# -# Check if atomic headers are up-to-date - -ATOMICDIR=$(dirname $0) -ATOMICTBL=${ATOMICDIR}/atomics.tbl -LINUXDIR=${ATOMICDIR}/../.. - -echo '' | sha1sum - > /dev/null 2>&1 -if [ $? -ne 0 ]; then - printf "sha1sum not available, skipping atomic header checks.\n" - exit 0 -fi - -cat < Date: Sat, 20 Aug 2022 18:15:30 +0900 Subject: kbuild: do not deduplicate modules.order The AWK code was added to deduplicate modules.order in case $(obj-m) contains the same module multiple times, but it is actually unneeded since commit b2c885549122 ("kbuild: update modules.order only when contained modules are updated"). The list is already deduplicated before being processed by AWK because $^ is the deduplicated list of prerequisites. (Please note the real-prereqs macro uses $^) Yet, modules.order will contain duplication if two different Makefiles build the same module: foo/Makefile: obj-m += bar/baz.o foo/bar/Makefile: obj-m += baz.o However, the parallel builds cannot properly handle this case in the first place. So, it is better to let it fail (as already done by scripts/modules-check.sh). Signed-off-by: Masahiro Yamada --- Makefile | 5 +---- scripts/Makefile.build | 2 +- 2 files changed, 2 insertions(+), 5 deletions(-) (limited to 'scripts') diff --git a/Makefile b/Makefile index 22a4afd51285..498095b3825e 100644 --- a/Makefile +++ b/Makefile @@ -1430,14 +1430,11 @@ endif # Build modules # -# A module can be listed more than once in obj-m resulting in -# duplicate lines in modules.order files. Those are removed -# using awk while concatenating to the final file. PHONY += modules modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare -cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@ +cmd_modules_order = cat $(real-prereqs) > $@ modules.order: $(subdir-modorder) FORCE $(call if_changed,modules_order) diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 784f46d41959..0df488d0bbb0 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -374,7 +374,7 @@ $(obj)/built-in.a: $(real-obj-y) FORCE cmd_modules_order = { $(foreach m, $(real-prereqs), \ $(if $(filter %/modules.order, $m), cat $m, echo $(patsubst %.o,%.ko,$m));) :; } \ - | $(AWK) '!x[$$0]++' - > $@ + > $@ $(obj)/modules.order: $(obj-m) FORCE $(call if_changed,modules_order) -- cgit v1.2.3-59-g8ed1b From 2df8220cc511326508ec4da2f43ef69311bdd7b9 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 28 Aug 2022 11:39:53 +0900 Subject: kbuild: build init/built-in.a just once Kbuild builds init/built-in.a twice; first during the ordinary directory descending, second from scripts/link-vmlinux.sh. We do this because UTS_VERSION contains the build version and the timestamp. We cannot update it during the normal directory traversal since we do not yet know if we need to update vmlinux. UTS_VERSION is temporarily calculated, but omitted from the update check. Otherwise, vmlinux would be rebuilt every time. When Kbuild results in running link-vmlinux.sh, it increments the version number in the .version file and takes the timestamp at that time to really fix UTS_VERSION. However, updating the same file twice is a footgun. To avoid nasty timestamp issues, all build artifacts that depend on init/built-in.a are atomically generated in link-vmlinux.sh, where some of them do not need rebuilding. To fix this issue, this commit changes as follows: [1] Split UTS_VERSION out to include/generated/utsversion.h from include/generated/compile.h include/generated/utsversion.h is generated just before the vmlinux link. It is generated under include/generated/ because some decompressors (s390, x86) use UTS_VERSION. [2] Split init_uts_ns and linux_banner out to init/version-timestamp.c from init/version.c init_uts_ns and linux_banner contain UTS_VERSION. During the ordinary directory descending, they are compiled with __weak and used to determine if vmlinux needs relinking. Just before the vmlinux link, they are compiled without __weak to embed the real version and timestamp. Signed-off-by: Masahiro Yamada --- arch/powerpc/boot/wrapper | 2 +- arch/s390/boot/version.c | 1 + arch/x86/boot/compressed/kaslr.c | 1 + arch/x86/boot/version.c | 1 + init/.gitignore | 2 + init/Makefile | 55 +++++++++++++++++++------ init/build-version | 10 +++++ init/version-timestamp.c | 31 ++++++++++++++ init/version.c | 36 ++++++---------- kernel/gen_kheaders.sh | 6 +-- scripts/link-vmlinux.sh | 17 ++------ scripts/mkcompile_h | 89 +++++----------------------------------- 12 files changed, 120 insertions(+), 131 deletions(-) create mode 100644 init/.gitignore create mode 100755 init/build-version create mode 100644 init/version-timestamp.c (limited to 'scripts') diff --git a/arch/powerpc/boot/wrapper b/arch/powerpc/boot/wrapper index 55978f32fa77..5bdd4dd20bbb 100755 --- a/arch/powerpc/boot/wrapper +++ b/arch/powerpc/boot/wrapper @@ -433,7 +433,7 @@ fi # Extract kernel version information, some platforms want to include # it in the image header version=`${CROSS}strings "$kernel" | grep '^Linux version [-0-9.]' | \ - cut -d' ' -f3` + head -n1 | cut -d' ' -f3` if [ -n "$version" ]; then uboot_version="-n Linux-$version" fi diff --git a/arch/s390/boot/version.c b/arch/s390/boot/version.c index d32e58bdda6a..fd32f038777f 100644 --- a/arch/s390/boot/version.c +++ b/arch/s390/boot/version.c @@ -1,4 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 +#include #include #include #include "boot.h" diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index 4a3f223973f4..e476bcbd9b42 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -29,6 +29,7 @@ #include #include #include +#include #include #define _SETUP diff --git a/arch/x86/boot/version.c b/arch/x86/boot/version.c index a1aaaf6c06a6..945383f0f606 100644 --- a/arch/x86/boot/version.c +++ b/arch/x86/boot/version.c @@ -11,6 +11,7 @@ */ #include "boot.h" +#include #include #include diff --git a/init/.gitignore b/init/.gitignore new file mode 100644 index 000000000000..cbbe270cec00 --- /dev/null +++ b/init/.gitignore @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0-only +/utsversion-tmp.h diff --git a/init/Makefile b/init/Makefile index d82623d7fc8e..ba90eb817185 100644 --- a/init/Makefile +++ b/init/Makefile @@ -19,20 +19,49 @@ mounts-y := do_mounts.o mounts-$(CONFIG_BLK_DEV_RAM) += do_mounts_rd.o mounts-$(CONFIG_BLK_DEV_INITRD) += do_mounts_initrd.o -# dependencies on generated files need to be listed explicitly -$(obj)/version.o: include/generated/compile.h +# +# UTS_VERSION +# + +smp-flag-$(CONFIG_SMP) := SMP +preempt-flag-$(CONFIG_PREEMPT_BUILD) := PREEMPT +preempt-flag-$(CONFIG_PREEMPT_DYNAMIC) := PREEMPT_DYNAMIC +preempt-flag-$(CONFIG_PREEMPT_RT) := PREEMPT_RT + +build-version = $(or $(KBUILD_BUILD_VERSION), $(build-version-auto)) +build-timestamp = $(or $(KBUILD_BUILD_TIMESTAMP), $(build-timestamp-auto)) + +# Maximum length of UTS_VERSION is 64 chars +filechk_uts_version = \ + utsver=$$(echo '$(pound)'"$(build-version)" $(smp-flag-y) $(preempt-flag-y) "$(build-timestamp)" | cut -b -64); \ + echo '$(pound)'define UTS_VERSION \""$${utsver}"\" + +# +# Build version.c with temporary UTS_VERSION +# -# compile.h changes depending on hostname, generation number, etc, -# so we regenerate it always. -# mkcompile_h will make sure to only update the -# actual file if its content has changed. +$(obj)/utsversion-tmp.h: FORCE + $(call filechk,uts_version) -quiet_cmd_compile.h = CHK $@ - cmd_compile.h = \ - $(CONFIG_SHELL) $(srctree)/scripts/mkcompile_h $@ \ - "$(UTS_MACHINE)" "$(CONFIG_SMP)" "$(CONFIG_PREEMPT_BUILD)" \ - "$(CONFIG_PREEMPT_DYNAMIC)" "$(CONFIG_PREEMPT_RT)" \ - "$(CONFIG_CC_VERSION_TEXT)" "$(LD)" +clean-files += utsversion-tmp.h + +$(obj)/version.o: include/generated/compile.h $(obj)/utsversion-tmp.h +CFLAGS_version.o := -include $(obj)/utsversion-tmp.h + +filechk_compile.h = $(srctree)/scripts/mkcompile_h \ + "$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)" include/generated/compile.h: FORCE - $(call cmd,compile.h) + $(call filechk,compile.h) + +# +# Build version-timestamp.c with final UTS_VERSION +# + +include/generated/utsversion.h: build-version-auto = $(shell $(srctree)/$(src)/build-version) +include/generated/utsversion.h: build-timestamp-auto = $(shell LC_ALL=C date) +include/generated/utsversion.h: FORCE + $(call filechk,uts_version) + +$(obj)/version-timestamp.o: include/generated/utsversion.h +CFLAGS_version-timestamp.o := -include include/generated/utsversion.h diff --git a/init/build-version b/init/build-version new file mode 100755 index 000000000000..537d45815083 --- /dev/null +++ b/init/build-version @@ -0,0 +1,10 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0-only + +prev_ver=$(cat .version 2>/dev/null) && +ver=$(expr ${prev_ver} + 1 2>/dev/null) || +ver=1 + +echo ${ver} > .version + +echo ${ver} diff --git a/init/version-timestamp.c b/init/version-timestamp.c new file mode 100644 index 000000000000..179e93bae539 --- /dev/null +++ b/init/version-timestamp.c @@ -0,0 +1,31 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include +#include +#include +#include +#include +#include +#include + +struct uts_namespace init_uts_ns = { + .ns.count = REFCOUNT_INIT(2), + .name = { + .sysname = UTS_SYSNAME, + .nodename = UTS_NODENAME, + .release = UTS_RELEASE, + .version = UTS_VERSION, + .machine = UTS_MACHINE, + .domainname = UTS_DOMAINNAME, + }, + .user_ns = &init_user_ns, + .ns.inum = PROC_UTS_INIT_INO, +#ifdef CONFIG_UTS_NS + .ns.ops = &utsns_operations, +#endif +}; + +/* FIXED STRINGS! Don't touch! */ +const char linux_banner[] = + "Linux version " UTS_RELEASE " (" LINUX_COMPILE_BY "@" + LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION "\n"; diff --git a/init/version.c b/init/version.c index 3391c4051bf3..01d4ab05f0ba 100644 --- a/init/version.c +++ b/init/version.c @@ -18,24 +18,6 @@ #include #include -struct uts_namespace init_uts_ns = { - .ns.count = REFCOUNT_INIT(2), - .name = { - .sysname = UTS_SYSNAME, - .nodename = UTS_NODENAME, - .release = UTS_RELEASE, - .version = UTS_VERSION, - .machine = UTS_MACHINE, - .domainname = UTS_DOMAINNAME, - }, - .user_ns = &init_user_ns, - .ns.inum = PROC_UTS_INIT_INO, -#ifdef CONFIG_UTS_NS - .ns.ops = &utsns_operations, -#endif -}; -EXPORT_SYMBOL_GPL(init_uts_ns); - static int __init early_hostname(char *arg) { size_t bufsize = sizeof(init_uts_ns.name.nodename); @@ -51,11 +33,6 @@ static int __init early_hostname(char *arg) } early_param("hostname", early_hostname); -/* FIXED STRINGS! Don't touch! */ -const char linux_banner[] = - "Linux version " UTS_RELEASE " (" LINUX_COMPILE_BY "@" - LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION "\n"; - const char linux_proc_banner[] = "%s version %s" " (" LINUX_COMPILE_BY "@" LINUX_COMPILE_HOST ")" @@ -63,3 +40,16 @@ const char linux_proc_banner[] = BUILD_SALT; BUILD_LTO_INFO; + +/* + * init_uts_ns and linux_banner contain the build version and timestamp, + * which are really fixed at the very last step of build process. + * They are compiled with __weak first, and without __weak later. + */ + +struct uts_namespace init_uts_ns __weak; +const char linux_banner[] __weak; + +#include "version-timestamp.c" + +EXPORT_SYMBOL_GPL(init_uts_ns); diff --git a/kernel/gen_kheaders.sh b/kernel/gen_kheaders.sh index 0c78e64f747d..473036b43c83 100755 --- a/kernel/gen_kheaders.sh +++ b/kernel/gen_kheaders.sh @@ -31,8 +31,8 @@ if [ "$building_out_of_srctree" ]; then fi all_dirs="$all_dirs $dir_list" -# include/generated/compile.h is ignored because it is touched even when none -# of the source files changed. +# include/generated/utsversion.h is ignored because it is generated after this +# script is executed. (utsversion.h is unneeded for kheaders) # # When Kconfig regenerates include/generated/autoconf.h, its timestamp is # updated, but the contents might be still the same. When any CONFIG option is @@ -42,7 +42,7 @@ all_dirs="$all_dirs $dir_list" # # Ignore them for md5 calculation to avoid pointless regeneration. headers_md5="$(find $all_dirs -name "*.h" | - grep -v "include/generated/compile.h" | + grep -v "include/generated/utsversion.h" | grep -v "include/generated/autoconf.h" | xargs ls -l | md5sum | cut -d ' ' -f1)" diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index eecc1863e556..8d982574145a 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -75,6 +75,8 @@ vmlinux_link() objs="${objs} .vmlinux.export.o" fi + objs="${objs} init/version-timestamp.o" + if [ "${SRCARCH}" = "um" ]; then wl=-Wl, ld="${CC}" @@ -213,19 +215,6 @@ if [ "$1" = "clean" ]; then exit 0 fi -# Update version -info GEN .version -if [ -r .version ]; then - VERSION=$(expr 0$(cat .version) + 1) - echo $VERSION > .version -else - rm -f .version - echo 1 > .version -fi; - -# final build of init/ -${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init need-builtin=1 - #link vmlinux.o ${MAKE} -f "${srctree}/scripts/Makefile.vmlinux_o" @@ -260,6 +249,8 @@ if is_enabled CONFIG_MODULES; then ${MAKE} -f "${srctree}/scripts/Makefile.vmlinux" .vmlinux.export.o fi +${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init init/version-timestamp.o + btf_vmlinux_bin_o="" if is_enabled CONFIG_DEBUG_INFO_BTF; then btf_vmlinux_bin_o=.btf.vmlinux.bin.o diff --git a/scripts/mkcompile_h b/scripts/mkcompile_h index ca40a5258c87..f1a820d49e53 100755 --- a/scripts/mkcompile_h +++ b/scripts/mkcompile_h @@ -1,14 +1,9 @@ #!/bin/sh # SPDX-License-Identifier: GPL-2.0 -TARGET=$1 -ARCH=$2 -SMP=$3 -PREEMPT=$4 -PREEMPT_DYNAMIC=$5 -PREEMPT_RT=$6 -CC_VERSION="$7" -LD=$8 +UTS_MACHINE=$1 +CC_VERSION="$2" +LD=$3 # Do not expand names set -f @@ -17,17 +12,6 @@ set -f LC_ALL=C export LC_ALL -if [ -z "$KBUILD_BUILD_VERSION" ]; then - VERSION=$(cat .version 2>/dev/null || echo 1) -else - VERSION=$KBUILD_BUILD_VERSION -fi - -if [ -z "$KBUILD_BUILD_TIMESTAMP" ]; then - TIMESTAMP=`date` -else - TIMESTAMP=$KBUILD_BUILD_TIMESTAMP -fi if test -z "$KBUILD_BUILD_USER"; then LINUX_COMPILE_BY=$(whoami | sed 's/\\/\\\\/') else @@ -39,63 +23,12 @@ else LINUX_COMPILE_HOST=$KBUILD_BUILD_HOST fi -UTS_VERSION="#$VERSION" -CONFIG_FLAGS="" -if [ -n "$SMP" ] ; then CONFIG_FLAGS="SMP"; fi - -if [ -n "$PREEMPT_RT" ] ; then - CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT_RT" -elif [ -n "$PREEMPT_DYNAMIC" ] ; then - CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT_DYNAMIC" -elif [ -n "$PREEMPT" ] ; then - CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT" -fi - -# Truncate to maximum length -UTS_LEN=64 -UTS_VERSION="$(echo $UTS_VERSION $CONFIG_FLAGS $TIMESTAMP | cut -b -$UTS_LEN)" - -# Generate a temporary compile.h - -{ echo /\* This file is auto generated, version $VERSION \*/ - if [ -n "$CONFIG_FLAGS" ] ; then echo "/* $CONFIG_FLAGS */"; fi +LD_VERSION=$($LD -v | head -n1 | sed 's/(compatible with [^)]*)//' \ + | sed 's/[[:space:]]*$//') - echo \#define UTS_MACHINE \"$ARCH\" - - echo \#define UTS_VERSION \"$UTS_VERSION\" - - printf '#define LINUX_COMPILE_BY "%s"\n' "$LINUX_COMPILE_BY" - echo \#define LINUX_COMPILE_HOST \"$LINUX_COMPILE_HOST\" - - LD_VERSION=$($LD -v | head -n1 | sed 's/(compatible with [^)]*)//' \ - | sed 's/[[:space:]]*$//') - printf '#define LINUX_COMPILER "%s"\n' "$CC_VERSION, $LD_VERSION" -} > .tmpcompile - -# Only replace the real compile.h if the new one is different, -# in order to preserve the timestamp and avoid unnecessary -# recompilations. -# We don't consider the file changed if only the date/time changed, -# unless KBUILD_BUILD_TIMESTAMP was explicitly set (e.g. for -# reproducible builds with that value referring to a commit timestamp). -# A kernel config change will increase the generation number, thus -# causing compile.h to be updated (including date/time) due to the -# changed comment in the -# first line. - -if [ -z "$KBUILD_BUILD_TIMESTAMP" ]; then - IGNORE_PATTERN="UTS_VERSION" -else - IGNORE_PATTERN="NOT_A_PATTERN_TO_BE_MATCHED" -fi - -if [ -r $TARGET ] && \ - grep -v $IGNORE_PATTERN $TARGET > .tmpver.1 && \ - grep -v $IGNORE_PATTERN .tmpcompile > .tmpver.2 && \ - cmp -s .tmpver.1 .tmpver.2; then - rm -f .tmpcompile -else - echo " UPD $TARGET" - mv -f .tmpcompile $TARGET -fi -rm -f .tmpver.1 .tmpver.2 +cat < Date: Sun, 28 Aug 2022 11:39:55 +0900 Subject: scripts/mkcompile_h: move LC_ALL=C to '$LD -v' Minimize the scope of LC_ALL=C like before commit 87c94bfb8ad3 ("kbuild: override build timestamp & version"). Give LC_ALL=C to '$LD -v' to get the consistent version output, as commit bcbcf50f5218 ("kbuild: fix ld-version.sh to not be affected by locale") mentioned the LD version is affected by locale. While I was here, I merged two sed invocations. Signed-off-by: Masahiro Yamada --- scripts/mkcompile_h | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'scripts') diff --git a/scripts/mkcompile_h b/scripts/mkcompile_h index f1a820d49e53..b76ccbbc094b 100755 --- a/scripts/mkcompile_h +++ b/scripts/mkcompile_h @@ -8,10 +8,6 @@ LD=$3 # Do not expand names set -f -# Fix the language to get consistent output -LC_ALL=C -export LC_ALL - if test -z "$KBUILD_BUILD_USER"; then LINUX_COMPILE_BY=$(whoami | sed 's/\\/\\\\/') else @@ -23,8 +19,8 @@ else LINUX_COMPILE_HOST=$KBUILD_BUILD_HOST fi -LD_VERSION=$($LD -v | head -n1 | sed 's/(compatible with [^)]*)//' \ - | sed 's/[[:space:]]*$//') +LD_VERSION=$(LC_ALL=C $LD -v | head -n1 | + sed -e 's/(compatible with [^)]*)//' -e 's/[[:space:]]*$//') cat < Date: Sun, 28 Aug 2022 11:39:56 +0900 Subject: Revert "kbuild: Make scripts/compile.h when sh != bash" This reverts commit [1] in the pre-git era. I do not know what problem happened in the script when sh != bash because there is no commit message. Now that this script is much simpler than it used to be, let's revert it, and let' see. (If this turns out to be problematic, fix the code with proper commit description.) [1]: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=11acbbbb8a50f4de7dbe4bc1b5acc440dfe81810 Signed-off-by: Masahiro Yamada --- scripts/mkcompile_h | 3 --- 1 file changed, 3 deletions(-) (limited to 'scripts') diff --git a/scripts/mkcompile_h b/scripts/mkcompile_h index b76ccbbc094b..2596f78e52ef 100755 --- a/scripts/mkcompile_h +++ b/scripts/mkcompile_h @@ -5,9 +5,6 @@ UTS_MACHINE=$1 CC_VERSION="$2" LD=$3 -# Do not expand names -set -f - if test -z "$KBUILD_BUILD_USER"; then LINUX_COMPILE_BY=$(whoami | sed 's/\\/\\\\/') else -- cgit v1.2.3-59-g8ed1b From 033a52d033607dab1c9b93962921dc6a9a9146b3 Mon Sep 17 00:00:00 2001 From: Owen Rafferty Date: Wed, 31 Aug 2022 15:57:08 -0500 Subject: kbuild: rewrite check-local-export in sh/awk Remove the bash build dependency for those who otherwise do not have it installed. This also provides a significant speedup: $ make defconfig $ make yes2modconfig ... $ find . -name "*.o" | grep -v vmlinux | wc 3169 3169 89615 $ export NM=nm $ time sh -c 'find . -name "*.o" | grep -v vmlinux | xargs -n1 ./scripts/check-local-export' Without patch: 0m15.90s real 0m12.17s user 0m05.28s system With patch: dash + nawk 0m02.16s real 0m02.92s user 0m00.34s system dash + busybox awk 0m02.36s real 0m03.36s user 0m00.34s system dash + gawk 0m02.07s real 0m03.26s user 0m00.32s system bash + gawk 0m03.55s real 0m05.00s user 0m00.54s system Signed-off-by: Owen Rafferty Signed-off-by: Masahiro Yamada --- scripts/check-local-export | 97 +++++++++++++++++++++++----------------------- 1 file changed, 48 insertions(+), 49 deletions(-) (limited to 'scripts') diff --git a/scripts/check-local-export b/scripts/check-local-export index 6ccc2f467416..f90b5a9c67b3 100755 --- a/scripts/check-local-export +++ b/scripts/check-local-export @@ -1,25 +1,14 @@ -#!/usr/bin/env bash +#!/bin/sh # SPDX-License-Identifier: GPL-2.0-only # # Copyright (C) 2022 Masahiro Yamada +# Copyright (C) 2022 Owen Rafferty # # Exit with error if a local exported symbol is found. # EXPORT_SYMBOL should be used for global symbols. set -e - -# catch errors from ${NM} -set -o pipefail - -# Run the last element of a pipeline in the current shell. -# Without this, the while-loop would be executed in a subshell, and -# the changes made to 'symbol_types' and 'export_symbols' would be lost. -shopt -s lastpipe - -declare -A symbol_types -declare -a export_symbols - -exit_code=0 +pid=$$ # If there is no symbol in the object, ${NM} (both GNU nm and llvm-nm) shows # 'no symbols' diagnostic (but exits with 0). It is harmless and hidden by @@ -29,43 +18,53 @@ exit_code=0 # TODO: # Use --quiet instead of 2>/dev/null when we upgrade the minimum version of # binutils to 2.37, llvm to 13.0.0. -# Then, the following line will be really simple: -# ${NM} --quiet ${1} | +# Then, the following line will be simpler: +# { ${NM} --quiet ${1} || kill 0; } | + +{ ${NM} ${1} 2>/dev/null || { echo "${0}: ${NM} failed" >&2; kill $pid; } } | +${AWK} -v "file=${1}" ' +BEGIN { + i = 0 +} + +# Skip the line if the number of fields is less than 3. +# +# case 1) +# For undefined symbols, the first field (value) is empty. +# The outout looks like this: +# " U _printk" +# It is unneeded to record undefined symbols. +# +# case 2) +# For Clang LTO, llvm-nm outputs a line with type t but empty name: +# "---------------- t" +!length($3) { + next +} -{ ${NM} ${1} 2>/dev/null || { echo "${0}: ${NM} failed" >&2; false; } } | -while read value type name -do - # Skip the line if the number of fields is less than 3. - # - # case 1) - # For undefined symbols, the first field (value) is empty. - # The outout looks like this: - # " U _printk" - # It is unneeded to record undefined symbols. - # - # case 2) - # For Clang LTO, llvm-nm outputs a line with type 't' but empty name: - # "---------------- t" - if [[ -z ${name} ]]; then - continue - fi +# save (name, type) in the associative array +{ symbol_types[$3]=$2 } - # save (name, type) in the associative array - symbol_types[${name}]=${type} +# append the exported symbol to the array +($3 ~ /^__ksymtab_/) { + export_symbols[i] = $3 + sub(/^__ksymtab_/, "", export_symbols[i]) + i++ +} - # append the exported symbol to the array - if [[ ${name} == __ksymtab_* ]]; then - export_symbols+=(${name#__ksymtab_}) - fi -done +END { + exit_code = 0 + for (j = 0; j < i; ++j) { + name = export_symbols[j] + # nm(3) says "If lowercase, the symbol is usually local" + if (symbol_types[name] ~ /[a-z]/) { + printf "%s: error: local symbol %s was exported\n", + file, name | "cat 1>&2" + exit_code = 1 + } + } -for name in "${export_symbols[@]}" -do - # nm(3) says "If lowercase, the symbol is usually local" - if [[ ${symbol_types[$name]} =~ [a-z] ]]; then - echo "$@: error: local symbol '${name}' was exported" >&2 - exit_code=1 - fi -done + exit exit_code +}' -exit ${exit_code} +exit $? -- cgit v1.2.3-59-g8ed1b From cc306abd19e8acdd85072b162d09e80408389cd8 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 6 Sep 2022 15:13:06 +0900 Subject: kbuild: fix and refactor single target build The single target build has a subtle bug for the combination for an individual file and a subdirectory. [1] 'make kernel/fork.i' builds only kernel/fork.i $ make kernel/fork.i CALL scripts/checksyscalls.sh DESCEND objtool CPP kernel/fork.i [2] 'make kernel/' builds only under the kernel/ directory. $ make kernel/ CALL scripts/checksyscalls.sh DESCEND objtool CC kernel/fork.o CC kernel/exec_domain.o [snip] CC kernel/rseq.o AR kernel/built-in.a But, if you try to do [1] and [2] in a single command, you will get only [1] with a weird log: $ make kernel/fork.i kernel/ CALL scripts/checksyscalls.sh DESCEND objtool CPP kernel/fork.i make[2]: Nothing to be done for 'kernel/'. With 'make kernel/fork.i kernel/', you should get both [1] and [2]. Rewrite the single target build. Signed-off-by: Masahiro Yamada --- Makefile | 9 ++++----- scripts/Makefile.build | 54 +++++++++++++++----------------------------------- 2 files changed, 20 insertions(+), 43 deletions(-) (limited to 'scripts') diff --git a/Makefile b/Makefile index f9756ff7c750..b0a3cba5af94 100644 --- a/Makefile +++ b/Makefile @@ -1819,11 +1819,11 @@ single_modpost: $(single-no-ko) modules_prepare $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost $(Q)rm -f $(MODORDER) -export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod_prefix), $(single-no-ko)) +single-goals := $(addprefix $(extmod_prefix), $(single-no-ko)) # trim unrelated directories build-dirs := $(foreach d, $(build-dirs), \ - $(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d))) + $(if $(filter $d/%, $(single-goals)), $d)) endif @@ -1835,9 +1835,8 @@ endif PHONY += descend $(build-dirs) descend: $(build-dirs) $(build-dirs): prepare - $(Q)$(MAKE) $(build)=$@ \ - single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \ - need-builtin=1 need-modorder=1 + $(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 \ + $(filter $@/%, $(single-goals)) clean-dirs := $(addprefix _clean_, $(clean-dirs)) PHONY += $(clean-dirs) clean diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 0df488d0bbb0..91d2e5461a3e 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -5,8 +5,8 @@ src := $(obj) -PHONY := __build -__build: +PHONY := $(obj)/ +$(obj)/: # Init all relevant variables used in kbuild files so # 1) they have correct type @@ -323,7 +323,7 @@ $(obj)/%.o: $(src)/%.S FORCE targets += $(filter-out $(subdir-builtin), $(real-obj-y)) targets += $(filter-out $(subdir-modorder), $(real-obj-m)) -targets += $(real-dtb-y) $(lib-y) $(always-y) $(MAKECMDGOALS) +targets += $(real-dtb-y) $(lib-y) $(always-y) # Linker scripts preprocessor (.lds.S -> .lds) # --------------------------------------------------------------------------- @@ -400,8 +400,6 @@ $(multi-obj-m): %.o: %.mod FORCE $(call if_changed_rule,ld_multi_m) $(call multi_depend, $(multi-obj-m), .o, -objs -y -m) -targets := $(filter-out $(PHONY), $(targets)) - # Add intermediate targets: # When building objects with specific suffix patterns, add intermediate # targets that the final targets are derived from. @@ -420,52 +418,29 @@ targets += $(call intermediate_targets, .asn1.o, .asn1.c .asn1.h) \ # Build # --------------------------------------------------------------------------- -ifdef single-build - -KBUILD_SINGLE_TARGETS := $(filter $(obj)/%, $(KBUILD_SINGLE_TARGETS)) - -curdir-single := $(sort $(foreach x, $(KBUILD_SINGLE_TARGETS), \ - $(if $(filter $(x) $(basename $(x)).o, $(targets)), $(x)))) - -# Handle single targets without any rule: show "Nothing to be done for ..." or -# "No rule to make target ..." depending on whether the target exists. -unknown-single := $(filter-out $(addsuffix /%, $(subdir-ym)), \ - $(filter-out $(curdir-single), $(KBUILD_SINGLE_TARGETS))) - -single-subdirs := $(foreach d, $(subdir-ym), \ - $(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d))) - -__build: $(curdir-single) $(single-subdirs) -ifneq ($(unknown-single),) - $(Q)$(MAKE) -f /dev/null $(unknown-single) -endif +$(obj)/: $(if $(KBUILD_BUILTIN), $(targets-for-builtin)) \ + $(if $(KBUILD_MODULES), $(targets-for-modules)) \ + $(subdir-ym) $(always-y) @: -ifeq ($(curdir-single),) -# Nothing to do in this directory. Do not include any .*.cmd file for speed-up -targets := -else -targets += $(curdir-single) -endif +# Single targets +# --------------------------------------------------------------------------- -else +single-subdirs := $(foreach d, $(subdir-ym), $(if $(filter $d/%, $(MAKECMDGOALS)), $d)) +single-subdir-goals := $(filter $(addsuffix /%, $(single-subdirs)), $(MAKECMDGOALS)) -__build: $(if $(KBUILD_BUILTIN), $(targets-for-builtin)) \ - $(if $(KBUILD_MODULES), $(targets-for-modules)) \ - $(subdir-ym) $(always-y) +$(single-subdir-goals): $(single-subdirs) @: -endif - # Descending # --------------------------------------------------------------------------- PHONY += $(subdir-ym) $(subdir-ym): $(Q)$(MAKE) $(build)=$@ \ - $(if $(filter $@/, $(KBUILD_SINGLE_TARGETS)),single-build=) \ need-builtin=$(if $(filter $@/built-in.a, $(subdir-builtin)),1) \ - need-modorder=$(if $(filter $@/modules.order, $(subdir-modorder)),1) + need-modorder=$(if $(filter $@/modules.order, $(subdir-modorder)),1) \ + $(filter $@/%, $(single-subdir-goals)) # Add FORCE to the prequisites of a target to force it to be always rebuilt. # --------------------------------------------------------------------------- @@ -474,6 +449,9 @@ PHONY += FORCE FORCE: +targets += $(filter-out $(single-subdir-goals), $(MAKECMDGOALS)) +targets := $(filter-out $(PHONY), $(targets)) + # Read all saved command lines and dependencies for the $(targets) we # may be building above, using $(if_changed{,_dep}). As an # optimization, we don't need to read them if the target does not -- cgit v1.2.3-59-g8ed1b From 9ec6ab6ee5ca72afdf8f60c330ad997825c0819b Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 7 Sep 2022 03:49:35 +0900 Subject: kbuild: use objtool-args-y to clean up objtool arguments Based on Linus' patch. Refactor scripts/Makefile.vmlinux_o as well. Link: https://lore.kernel.org/lkml/CAHk-=wgjTMQgiKzBZTmb=uWGDEQxDdyF1+qxBkODYciuNsmwnw@mail.gmail.com/ Suggested-by: Linus Torvalds Signed-off-by: Masahiro Yamada Acked-by: Peter Zijlstra Reviewed-by: Nick Desaulniers --- scripts/Makefile.lib | 31 ++++++++++++++++--------------- scripts/Makefile.vmlinux_o | 15 ++++----------- 2 files changed, 20 insertions(+), 26 deletions(-) (limited to 'scripts') diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 3fb6a99e78c4..52811b2783de 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -229,25 +229,26 @@ ifdef CONFIG_OBJTOOL objtool := $(objtree)/tools/objtool/objtool -objtool_args = \ - $(if $(CONFIG_HAVE_JUMP_LABEL_HACK), --hacks=jump_label) \ - $(if $(CONFIG_HAVE_NOINSTR_HACK), --hacks=noinstr) \ - $(if $(CONFIG_X86_KERNEL_IBT), --ibt) \ - $(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount) \ - $(if $(CONFIG_UNWINDER_ORC), --orc) \ - $(if $(CONFIG_RETPOLINE), --retpoline) \ - $(if $(CONFIG_RETHUNK), --rethunk) \ - $(if $(CONFIG_SLS), --sls) \ - $(if $(CONFIG_STACK_VALIDATION), --stackval) \ - $(if $(CONFIG_HAVE_STATIC_CALL_INLINE), --static-call) \ - $(if $(CONFIG_HAVE_UACCESS_VALIDATION), --uaccess) \ +objtool-args-$(CONFIG_HAVE_JUMP_LABEL_HACK) += --hacks=jump_label +objtool-args-$(CONFIG_HAVE_NOINSTR_HACK) += --hacks=noinstr +objtool-args-$(CONFIG_X86_KERNEL_IBT) += --ibt +objtool-args-$(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL) += --mcount +objtool-args-$(CONFIG_UNWINDER_ORC) += --orc +objtool-args-$(CONFIG_RETPOLINE) += --retpoline +objtool-args-$(CONFIG_RETHUNK) += --rethunk +objtool-args-$(CONFIG_SLS) += --sls +objtool-args-$(CONFIG_STACK_VALIDATION) += --stackval +objtool-args-$(CONFIG_HAVE_STATIC_CALL_INLINE) += --static-call +objtool-args-$(CONFIG_HAVE_UACCESS_VALIDATION) += --uaccess +objtool-args-$(CONFIG_GCOV_KERNEL) += --no-unreachable + +objtool-args = $(objtool-args-y) \ $(if $(delay-objtool), --link) \ - $(if $(part-of-module), --module) \ - $(if $(CONFIG_GCOV_KERNEL), --no-unreachable) + $(if $(part-of-module), --module) delay-objtool := $(or $(CONFIG_LTO_CLANG),$(CONFIG_X86_KERNEL_IBT)) -cmd_objtool = $(if $(objtool-enabled), ; $(objtool) $(objtool_args) $@) +cmd_objtool = $(if $(objtool-enabled), ; $(objtool) $(objtool-args) $@) cmd_gen_objtooldep = $(if $(objtool-enabled), { echo ; echo '$@: $$(wildcard $(objtool))' ; } >> $(dot-target).cmd) endif # CONFIG_OBJTOOL diff --git a/scripts/Makefile.vmlinux_o b/scripts/Makefile.vmlinux_o index 84019814f33f..7d531b825712 100644 --- a/scripts/Makefile.vmlinux_o +++ b/scripts/Makefile.vmlinux_o @@ -35,18 +35,11 @@ endif objtool-enabled := $(or $(delay-objtool),$(CONFIG_NOINSTR_VALIDATION)) -# Reuse objtool_args defined in scripts/Makefile.lib if LTO or IBT is enabled. -# -# Add some more flags as needed. -# --no-unreachable and --link might be added twice, but it is fine. -# -# Expand objtool_args to a simple variable to avoid circular reference. +vmlinux-objtool-args-$(delay-objtool) += $(objtool-args-y) +vmlinux-objtool-args-$(CONFIG_GCOV_KERNEL) += --no-unreachable +vmlinux-objtool-args-$(CONFIG_NOINSTR_VALIDATION) += --noinstr $(if $(CONFIG_CPU_UNRET_ENTRY), --unret) -objtool_args := \ - $(if $(delay-objtool),$(objtool_args)) \ - $(if $(CONFIG_NOINSTR_VALIDATION), --noinstr $(if $(CONFIG_CPU_UNRET_ENTRY), --unret)) \ - $(if $(CONFIG_GCOV_KERNEL), --no-unreachable) \ - --link +objtool-args = $(vmlinux-objtool-args-y) --link # Link of vmlinux.o used for section mismatch analysis # --------------------------------------------------------------------------- -- cgit v1.2.3-59-g8ed1b From efc8338e3a72baf95294634b48c5f2d80dce1c5c Mon Sep 17 00:00:00 2001 From: Zeng Heng Date: Wed, 14 Sep 2022 09:59:06 +0800 Subject: Kconfig: remove sym_set_choice_value sym_set_choice_value could be removed and directly call sym_set_tristate_value instead. Signed-off-by: Zeng Heng Suggested-by: Masahiro Yamada Signed-off-by: Masahiro Yamada --- scripts/kconfig/conf.c | 2 +- scripts/kconfig/lkc.h | 5 ----- 2 files changed, 1 insertion(+), 6 deletions(-) (limited to 'scripts') diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c index 4178065ca27f..33d19e419908 100644 --- a/scripts/kconfig/conf.c +++ b/scripts/kconfig/conf.c @@ -551,7 +551,7 @@ static int conf_choice(struct menu *menu) print_help(child); continue; } - sym_set_choice_value(sym, child->sym); + sym_set_tristate_value(child->sym, yes); for (child = child->list; child; child = child->next) { indent += 2; conf(child); diff --git a/scripts/kconfig/lkc.h b/scripts/kconfig/lkc.h index c396aa104090..6ac2eabe109d 100644 --- a/scripts/kconfig/lkc.h +++ b/scripts/kconfig/lkc.h @@ -123,11 +123,6 @@ static inline struct symbol *sym_get_choice_value(struct symbol *sym) return (struct symbol *)sym->curr.val; } -static inline bool sym_set_choice_value(struct symbol *ch, struct symbol *chval) -{ - return sym_set_tristate_value(chval, yes); -} - static inline bool sym_is_choice(struct symbol *sym) { return sym->flags & SYMBOL_CHOICE ? true : false; -- cgit v1.2.3-59-g8ed1b From a8d5692659358eba46d3b2f7d96da7c390f41f71 Mon Sep 17 00:00:00 2001 From: Zeng Heng Date: Wed, 14 Sep 2022 20:09:21 +0800 Subject: scripts: remove unused argument 'type' Remove unused function argument, and there is no logic changes. Signed-off-by: Zeng Heng Signed-off-by: Masahiro Yamada --- scripts/asn1_compiler.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'scripts') diff --git a/scripts/asn1_compiler.c b/scripts/asn1_compiler.c index adabd4145264..71d4a7c87900 100644 --- a/scripts/asn1_compiler.c +++ b/scripts/asn1_compiler.c @@ -832,7 +832,7 @@ static void parse(void) static struct element *element_list; -static struct element *alloc_elem(struct token *type) +static struct element *alloc_elem(void) { struct element *e = calloc(1, sizeof(*e)); if (!e) { @@ -860,7 +860,7 @@ static struct element *parse_type(struct token **_cursor, struct token *end, char *p; int labelled = 0, implicit = 0; - top = element = alloc_elem(cursor); + top = element = alloc_elem(); element->class = ASN1_UNIV; element->method = ASN1_PRIM; element->tag = token_to_tag[cursor->token_type]; @@ -939,7 +939,7 @@ static struct element *parse_type(struct token **_cursor, struct token *end, if (!implicit) element->method |= ASN1_CONS; element->compound = implicit ? TAG_OVERRIDE : SEQUENCE; - element->children = alloc_elem(cursor); + element->children = alloc_elem(); element = element->children; element->class = ASN1_UNIV; element->method = ASN1_PRIM; -- cgit v1.2.3-59-g8ed1b From 2e07005f4813a9ff6e895787e0c2d1fea859b033 Mon Sep 17 00:00:00 2001 From: Janis Schoetterl-Glausch Date: Fri, 16 Sep 2022 14:41:12 +0200 Subject: kbuild: rpm-pkg: fix breakage when V=1 is used Doing make V=1 binrpm-pkg results in: Executing(%install): /bin/sh -e /var/tmp/rpm-tmp.EgV6qJ + umask 022 + cd . + /bin/rm -rf /home/scgl/rpmbuild/BUILDROOT/kernel-6.0.0_rc5+-1.s390x + /bin/mkdir -p /home/scgl/rpmbuild/BUILDROOT + /bin/mkdir /home/scgl/rpmbuild/BUILDROOT/kernel-6.0.0_rc5+-1.s390x + mkdir -p /home/scgl/rpmbuild/BUILDROOT/kernel-6.0.0_rc5+-1.s390x/boot + make -f ./Makefile image_name + cp test -e include/generated/autoconf.h -a -e include/config/auto.conf || ( \ echo >&2; \ echo >&2 " ERROR: Kernel configuration is invalid."; \ echo >&2 " include/generated/autoconf.h or include/config/auto.conf are missing.";\ echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \ echo >&2 ; \ /bin/false) arch/s390/boot/bzImage /home/scgl/rpmbuild/BUILDROOT/kernel-6.0.0_rc5+-1.s390x/boot/vmlinuz-6.0.0-rc5+ cp: invalid option -- 'e' Try 'cp --help' for more information. error: Bad exit status from /var/tmp/rpm-tmp.EgV6qJ (%install) Because the make call to get the image name is verbose and prints additional information. Fixes: 993bdde94547 ("kbuild: add image_name to no-sync-config-targets") Signed-off-by: Janis Schoetterl-Glausch Signed-off-by: Masahiro Yamada --- scripts/package/mkspec | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/package/mkspec b/scripts/package/mkspec index 8fa7c5b8a1a1..c920c1b18e7a 100755 --- a/scripts/package/mkspec +++ b/scripts/package/mkspec @@ -88,10 +88,10 @@ $S mkdir -p %{buildroot}/boot %ifarch ia64 mkdir -p %{buildroot}/boot/efi - cp \$($MAKE image_name) %{buildroot}/boot/efi/vmlinuz-$KERNELRELEASE + cp \$($MAKE -s image_name) %{buildroot}/boot/efi/vmlinuz-$KERNELRELEASE ln -s efi/vmlinuz-$KERNELRELEASE %{buildroot}/boot/ %else - cp \$($MAKE image_name) %{buildroot}/boot/vmlinuz-$KERNELRELEASE + cp \$($MAKE -s image_name) %{buildroot}/boot/vmlinuz-$KERNELRELEASE %endif $M $MAKE %{?_smp_mflags} INSTALL_MOD_PATH=%{buildroot} modules_install $MAKE %{?_smp_mflags} INSTALL_HDR_PATH=%{buildroot}/usr headers_install -- cgit v1.2.3-59-g8ed1b From 88b61e3bff93f99712718db785b4aa0c1165f35c Mon Sep 17 00:00:00 2001 From: Nick Desaulniers Date: Mon, 19 Sep 2022 10:08:28 -0700 Subject: Makefile.compiler: replace cc-ifversion with compiler-specific macros cc-ifversion is GCC specific. Replace it with compiler specific variants. Update the users of cc-ifversion to use these new macros. Link: https://github.com/ClangBuiltLinux/linux/issues/350 Link: https://lore.kernel.org/llvm/CAGG=3QWSAUakO42kubrCap8fp-gm1ERJJAYXTnP1iHk_wrH=BQ@mail.gmail.com/ Suggested-by: Bill Wendling Reviewed-by: Nathan Chancellor Signed-off-by: Nick Desaulniers Signed-off-by: Masahiro Yamada --- Documentation/kbuild/makefiles.rst | 29 +++++++++++++++++------------ Makefile | 6 ++---- drivers/gpu/drm/amd/display/dc/dml/Makefile | 2 +- scripts/Makefile.compiler | 10 +++++++--- scripts/Makefile.extrawarn | 4 ++-- 5 files changed, 29 insertions(+), 22 deletions(-) (limited to 'scripts') diff --git a/Documentation/kbuild/makefiles.rst b/Documentation/kbuild/makefiles.rst index 11a296e52d68..ee7e3ea1fbe1 100644 --- a/Documentation/kbuild/makefiles.rst +++ b/Documentation/kbuild/makefiles.rst @@ -682,22 +682,27 @@ more details, with real examples. In the above example, -Wno-unused-but-set-variable will be added to KBUILD_CFLAGS only if gcc really accepts it. - cc-ifversion - cc-ifversion tests the version of $(CC) and equals the fourth parameter - if version expression is true, or the fifth (if given) if the version - expression is false. + gcc-min-version + gcc-min-version tests if the value of $(CONFIG_GCC_VERSION) is greater than + or equal to the provided value and evaluates to y if so. Example:: - #fs/reiserfs/Makefile - ccflags-y := $(call cc-ifversion, -lt, 0402, -O1) + cflags-$(call gcc-min-version, 70100) := -foo - In this example, ccflags-y will be assigned the value -O1 if the - $(CC) version is less than 4.2. - cc-ifversion takes all the shell operators: - -eq, -ne, -lt, -le, -gt, and -ge - The third parameter may be a text as in this example, but it may also - be an expanded variable or a macro. + In this example, cflags-y will be assigned the value -foo if $(CC) is gcc and + $(CONFIG_GCC_VERSION) is >= 7.1. + + clang-min-version + clang-min-version tests if the value of $(CONFIG_CLANG_VERSION) is greater + than or equal to the provided value and evaluates to y if so. + + Example:: + + cflags-$(call clang-min-version, 110000) := -foo + + In this example, cflags-y will be assigned the value -foo if $(CC) is clang + and $(CONFIG_CLANG_VERSION) is >= 11.0.0. cc-cross-prefix cc-cross-prefix is used to check if there exists a $(CC) in path with diff --git a/Makefile b/Makefile index b0a3cba5af94..09c9d9a005bd 100644 --- a/Makefile +++ b/Makefile @@ -790,7 +790,6 @@ KBUILD_CFLAGS += $(stackp-flags-y) KBUILD_CFLAGS-$(CONFIG_WERROR) += -Werror KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds -KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH) ifdef CONFIG_CC_IS_CLANG KBUILD_CPPFLAGS += -Qunused-arguments @@ -972,7 +971,6 @@ ifdef CONFIG_CC_IS_GCC KBUILD_CFLAGS += -Wno-maybe-uninitialized endif -ifdef CONFIG_CC_IS_GCC # The allocators already balk at large sizes, so silence the compiler # warnings for bounds checks involving those possible values. While # -Wno-alloc-size-larger-than would normally be used here, earlier versions @@ -984,8 +982,8 @@ ifdef CONFIG_CC_IS_GCC # ignored, continuing to default to PTRDIFF_MAX. So, left with no other # choice, we must perform a versioned check to disable this warning. # https://lore.kernel.org/lkml/20210824115859.187f272f@canb.auug.org.au -KBUILD_CFLAGS += $(call cc-ifversion, -ge, 0901, -Wno-alloc-size-larger-than) -endif +KBUILD_CFLAGS-$(call gcc-min-version, 90100) += -Wno-alloc-size-larger-than +KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH) # disable invalid "can't wrap" optimizations for signed / pointers KBUILD_CFLAGS += -fno-strict-overflow diff --git a/drivers/gpu/drm/amd/display/dc/dml/Makefile b/drivers/gpu/drm/amd/display/dc/dml/Makefile index cb81ed2fbd53..d70838edba80 100644 --- a/drivers/gpu/drm/amd/display/dc/dml/Makefile +++ b/drivers/gpu/drm/amd/display/dc/dml/Makefile @@ -34,7 +34,7 @@ dml_ccflags := -mhard-float -maltivec endif ifdef CONFIG_CC_IS_GCC -ifeq ($(call cc-ifversion, -lt, 0701, y), y) +ifneq ($(call gcc-min-version, 70100),y) IS_OLD_GCC = 1 endif endif diff --git a/scripts/Makefile.compiler b/scripts/Makefile.compiler index 94d0d40cddb3..20d353dcabfb 100644 --- a/scripts/Makefile.compiler +++ b/scripts/Makefile.compiler @@ -61,9 +61,13 @@ cc-option-yn = $(call try-run,\ cc-disable-warning = $(call try-run,\ $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1))) -# cc-ifversion -# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1) -cc-ifversion = $(shell [ $(CONFIG_GCC_VERSION)0 $(1) $(2)000 ] && echo $(3) || echo $(4)) +# gcc-min-version +# Usage: cflags-$(call gcc-min-version, 70100) += -foo +gcc-min-version = $(shell [ $(CONFIG_GCC_VERSION)0 -ge $(1)0 ] && echo y) + +# clang-min-version +# Usage: cflags-$(call clang-min-version, 110000) += -foo +clang-min-version = $(shell [ $(CONFIG_CLANG_VERSION)0 -ge $(1)0 ] && echo y) # ld-option # Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y) diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn index 6ae482158bc4..5769c1939d40 100644 --- a/scripts/Makefile.extrawarn +++ b/scripts/Makefile.extrawarn @@ -48,7 +48,7 @@ else ifdef CONFIG_CC_IS_CLANG KBUILD_CFLAGS += -Wno-initializer-overrides # Clang before clang-16 would warn on default argument promotions. -ifeq ($(shell [ $(CONFIG_CLANG_VERSION) -lt 160000 ] && echo y),y) +ifneq ($(call clang-min-version, 160000),y) # Disable -Wformat KBUILD_CFLAGS += -Wno-format # Then re-enable flags that were part of the -Wformat group that aren't @@ -56,7 +56,7 @@ KBUILD_CFLAGS += -Wno-format KBUILD_CFLAGS += -Wformat-extra-args -Wformat-invalid-specifier KBUILD_CFLAGS += -Wformat-zero-length -Wnonnull # Requires clang-12+. -ifeq ($(shell [ $(CONFIG_CLANG_VERSION) -ge 120000 ] && echo y),y) +ifeq ($(call clang-min-version, 120000),y) KBUILD_CFLAGS += -Wformat-insufficient-args endif endif -- cgit v1.2.3-59-g8ed1b From 5750121ae7382ebac8d47ce6d68012d6cd1d7926 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 25 Sep 2022 03:19:10 +0900 Subject: kbuild: list sub-directories in ./Kbuild Use the ordinary obj-y syntax to list subdirectories. Note1: Previously, the link order of lib-y depended on CONFIG_MODULES; lib-y was linked before drivers-y when CONFIG_MODULES=y, otherwise after drivers-y. This was a bug of commit 7273ad2b08f8 ("kbuild: link lib-y objects to vmlinux forcibly when CONFIG_MODULES=y"), but it was not a big deal after all. Now, all objects listed in lib-y are linked last, irrespective of CONFIG_MODULES. Note2: Finally, the single target build in arch/*/lib/ works correctly. There was a bug report about this. [1] $ make ARCH=arm arch/arm/lib/findbit.o CALL scripts/checksyscalls.sh AS arch/arm/lib/findbit.o [1]: https://lore.kernel.org/linux-kbuild/YvUQOwL6lD4%2F5%2FU6@shell.armlinux.org.uk/ Signed-off-by: Masahiro Yamada Tested-by: Nick Desaulniers Reviewed-by: Nicolas Schier --- Kbuild | 24 ++++++++++++++++++++ Makefile | 63 +++++++++++++++++----------------------------------- scripts/Makefile.lib | 2 ++ 3 files changed, 46 insertions(+), 43 deletions(-) (limited to 'scripts') diff --git a/Kbuild b/Kbuild index 0b9e8a16a621..8a37584d1fd6 100644 --- a/Kbuild +++ b/Kbuild @@ -72,3 +72,27 @@ $(atomic-checks): $(obj)/.checked-%: include/linux/atomic/% FORCE PHONY += prepare prepare: $(offsets-file) missing-syscalls $(atomic-checks) @: + +# Ordinary directory descending +# --------------------------------------------------------------------------- + +obj-y += init/ +obj-y += usr/ +obj-y += arch/$(SRCARCH)/ +obj-y += $(ARCH_CORE) +obj-y += kernel/ +obj-y += certs/ +obj-y += mm/ +obj-y += fs/ +obj-y += ipc/ +obj-y += security/ +obj-y += crypto/ +obj-$(CONFIG_BLOCK) += block/ +obj-$(CONFIG_IO_URING) += io_uring/ +obj-y += $(ARCH_LIB) +obj-y += drivers/ +obj-y += sound/ +obj-$(CONFIG_SAMPLES) += samples/ +obj-$(CONFIG_NET) += net/ +obj-y += virt/ +obj-y += $(ARCH_DRIVERS) diff --git a/Makefile b/Makefile index 09c9d9a005bd..317e9f09440c 100644 --- a/Makefile +++ b/Makefile @@ -676,11 +676,8 @@ endif ifeq ($(KBUILD_EXTMOD),) # Objects we will link into vmlinux / subdirs we need to visit -core-y := init/ usr/ arch/$(SRCARCH)/ -drivers-y := drivers/ sound/ -drivers-$(CONFIG_SAMPLES) += samples/ -drivers-$(CONFIG_NET) += net/ -drivers-y += virt/ +core-y := +drivers-y := libs-y := lib/ endif # KBUILD_EXTMOD @@ -1099,31 +1096,24 @@ export MODORDER := $(extmod_prefix)modules.order export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps ifeq ($(KBUILD_EXTMOD),) -core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ -core-$(CONFIG_BLOCK) += block/ -core-$(CONFIG_IO_URING) += io_uring/ -vmlinux-dirs := $(patsubst %/,%,$(filter %/, \ - $(core-y) $(core-m) $(drivers-y) $(drivers-m) \ - $(libs-y) $(libs-m))) - -build-dirs := $(vmlinux-dirs) -clean-dirs := $(sort $(vmlinux-dirs) Documentation . \ +build-dir := . +clean-dirs := $(sort . Documentation \ $(patsubst %/,%,$(filter %/, $(core-) \ $(drivers-) $(libs-)))) -subdir-modorder := $(addsuffix /modules.order, $(build-dirs)) - +export ARCH_CORE := $(core-y) +export ARCH_LIB := $(filter %/, $(libs-y)) +export ARCH_DRIVERS := $(drivers-y) $(drivers-m) # Externally visible symbols (used by link-vmlinux.sh) -KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y)) -KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y))) + +KBUILD_VMLINUX_OBJS := $(head-y) ./built-in.a ifdef CONFIG_MODULES KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y))) KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y)) else KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y)) endif -KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y)) export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds @@ -1138,7 +1128,7 @@ ifdef CONFIG_TRIM_UNUSED_KSYMS # (this can be evaluated only once include/config/auto.conf has been included) KBUILD_MODULES := 1 -autoksyms_recursive: descend modules.order +autoksyms_recursive: $(build-dir) modules.order $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \ "$(MAKE) -f $(srctree)/Makefile autoksyms_recursive" endif @@ -1166,7 +1156,7 @@ targets := vmlinux # The actual objects are generated when descending, # make sure no implicit rule kicks in -$(sort $(vmlinux-deps) $(subdir-modorder)): descend ; +$(sort $(vmlinux-deps)): . ; filechk_kernel.release = \ echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))" @@ -1437,13 +1427,6 @@ endif modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_prepare -cmd_modules_order = cat $(real-prereqs) > $@ - -modules.order: $(subdir-modorder) FORCE - $(call if_changed,modules_order) - -targets += modules.order - # Target to prepare building external modules modules_prepare: prepare $(Q)$(MAKE) $(build)=scripts scripts/module.lds @@ -1714,9 +1697,7 @@ else # KBUILD_EXTMOD KBUILD_BUILTIN := KBUILD_MODULES := 1 -build-dirs := $(KBUILD_EXTMOD) -$(MODORDER): descend - @: +build-dir := $(KBUILD_EXTMOD) compile_commands.json: $(extmod_prefix)compile_commands.json PHONY += compile_commands.json @@ -1754,6 +1735,9 @@ PHONY += modules modules_install modules_prepare ifdef CONFIG_MODULES +$(MODORDER): $(build-dir) + @: + modules: modules_check $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost @@ -1807,7 +1791,7 @@ single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \ $(single-ko): single_modpost @: -$(single-no-ko): descend +$(single-no-ko): $(build-dir) @: # Remove MODORDER when done because it is not the real one. @@ -1817,24 +1801,17 @@ single_modpost: $(single-no-ko) modules_prepare $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost $(Q)rm -f $(MODORDER) -single-goals := $(addprefix $(extmod_prefix), $(single-no-ko)) - -# trim unrelated directories -build-dirs := $(foreach d, $(build-dirs), \ - $(if $(filter $d/%, $(single-goals)), $d)) +single-goals := $(addprefix $(build-dir)/, $(single-no-ko)) endif -# Handle descending into subdirectories listed in $(build-dirs) # Preset locale variables to speed up the build process. Limit locale # tweaks to this spot to avoid wrong language settings when running # make menuconfig etc. # Error messages still appears in the original language -PHONY += descend $(build-dirs) -descend: $(build-dirs) -$(build-dirs): prepare - $(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 \ - $(filter $@/%, $(single-goals)) +PHONY += $(build-dir) +$(build-dir): prepare + $(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals) clean-dirs := $(addprefix _clean_, $(clean-dirs)) PHONY += $(clean-dirs) clean diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 52811b2783de..b7e650bc70f2 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -89,6 +89,7 @@ always-y += $(dtb-y) # Add subdir path +ifneq ($(obj),.) extra-y := $(addprefix $(obj)/,$(extra-y)) always-y := $(addprefix $(obj)/,$(always-y)) targets := $(addprefix $(obj)/,$(targets)) @@ -100,6 +101,7 @@ multi-obj-m := $(addprefix $(obj)/, $(multi-obj-m)) multi-dtb-y := $(addprefix $(obj)/, $(multi-dtb-y)) real-dtb-y := $(addprefix $(obj)/, $(real-dtb-y)) subdir-ym := $(addprefix $(obj)/,$(subdir-ym)) +endif # Finds the multi-part object the current object will be linked into. # If the object belongs to two or more multi-part objects, list them all. -- cgit v1.2.3-59-g8ed1b From 26ef40de5cbb24728a34a319e8d42cdec99f186c Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 25 Sep 2022 03:19:11 +0900 Subject: kbuild: move .vmlinux.objs rule to Makefile.modpost .vmlinux.objs is used by modpost, so scripts/Makefile.modpost is a better place to generate it. It is used only when CONFIG_MODVERSIONS=y. It should be guarded by "ifdef CONFIG_MODVERSIONS". Signed-off-by: Masahiro Yamada Tested-by: Nick Desaulniers Reviewed-by: Nicolas Schier --- Makefile | 2 +- scripts/Makefile.modpost | 30 ++++++++++++++++++++++++++++-- scripts/link-vmlinux.sh | 18 ------------------ 3 files changed, 29 insertions(+), 21 deletions(-) (limited to 'scripts') diff --git a/Makefile b/Makefile index 317e9f09440c..dac4ca2b900c 100644 --- a/Makefile +++ b/Makefile @@ -1477,7 +1477,7 @@ endif # CONFIG_MODULES # Directories & files removed with 'make clean' CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \ modules.builtin modules.builtin.modinfo modules.nsdeps \ - compile_commands.json .thinlto-cache + compile_commands.json .thinlto-cache .vmlinux.objs # Directories & files removed with 'make mrproper' MRPROPER_FILES += include/config include/generated \ diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index 911606496341..04ad00917b2f 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -57,6 +57,32 @@ vmlinux.symvers: vmlinux.o __modpost: vmlinux.symvers +# Generate the list of in-tree objects in vmlinux +# --------------------------------------------------------------------------- + +# This is used to retrieve symbol versions generated by genksyms. +ifdef CONFIG_MODVERSIONS +vmlinux.symvers: .vmlinux.objs +endif + +# Ignore libgcc.a +# Some architectures do '$(CC) --print-libgcc-file-name' to borrow libgcc.a +# from the toolchain, but there is no EXPORT_SYMBOL in it. + +quiet_cmd_vmlinux_objs = GEN $@ + cmd_vmlinux_objs = \ + for f in $(real-prereqs); do \ + case $${f} in \ + *libgcc.a) ;; \ + *.a) $(AR) t $${f} ;; \ + *) echo $${f} ;; \ + esac \ + done > $@ + +targets += .vmlinux.objs +.vmlinux.objs: $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS) FORCE + $(call if_changed,vmlinux_objs) + else ifeq ($(KBUILD_EXTMOD),) @@ -134,6 +160,8 @@ ifneq ($(KBUILD_MODPOST_NOFINAL),1) $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal endif +endif + PHONY += FORCE FORCE: @@ -141,6 +169,4 @@ existing-targets := $(wildcard $(sort $(targets))) -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd) -endif - .PHONY: $(PHONY) diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 8d982574145a..161bca64e8aa 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -199,7 +199,6 @@ cleanup() rm -f System.map rm -f vmlinux rm -f vmlinux.map - rm -f .vmlinux.objs rm -f .vmlinux.export.c } @@ -218,23 +217,6 @@ fi #link vmlinux.o ${MAKE} -f "${srctree}/scripts/Makefile.vmlinux_o" -# Generate the list of in-tree objects in vmlinux -# -# This is used to retrieve symbol versions generated by genksyms. -for f in ${KBUILD_VMLINUX_OBJS} ${KBUILD_VMLINUX_LIBS}; do - case ${f} in - *libgcc.a) - # Some architectures do '$(CC) --print-libgcc-file-name' to - # borrow libgcc.a from the toolchain. - # There is no EXPORT_SYMBOL in external objects. Ignore this. - ;; - *.a) - ${AR} t ${f} ;; - *) - echo ${f} ;; - esac -done > .vmlinux.objs - # modpost vmlinux.o to check for section mismatches ${MAKE} -f "${srctree}/scripts/Makefile.modpost" MODPOST_VMLINUX=1 -- cgit v1.2.3-59-g8ed1b From 9c5a0ac3c36917c4258f734bda98be02ca36b992 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 25 Sep 2022 03:19:12 +0900 Subject: kbuild: move vmlinux.o rule to the top Makefile Move the build rules of vmlinux.o out of scripts/link-vmlinux.sh to clearly separate 1) pre-modpost, 2) modpost, 3) post-modpost stages. This will make further refactoring possible. Signed-off-by: Masahiro Yamada Tested-by: Nick Desaulniers Reviewed-by: Nicolas Schier --- Makefile | 9 +++++---- scripts/link-vmlinux.sh | 3 --- 2 files changed, 5 insertions(+), 7 deletions(-) (limited to 'scripts') diff --git a/Makefile b/Makefile index dac4ca2b900c..21c41a03d98d 100644 --- a/Makefile +++ b/Makefile @@ -1118,8 +1118,6 @@ endif export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds -vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS) - # Recurse until adjust_autoksyms.sh is satisfied PHONY += autoksyms_recursive ifdef CONFIG_TRIM_UNUSED_KSYMS @@ -1142,6 +1140,9 @@ quiet_cmd_autoksyms_h = GEN $@ $(autoksyms_h): $(call cmd,autoksyms_h) +vmlinux.o: autoksyms_recursive $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS) FORCE + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o + ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink) # Final link of vmlinux with optional arch pass after final link @@ -1149,14 +1150,14 @@ cmd_link-vmlinux = \ $(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)"; \ $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true) -vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE +vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) FORCE +$(call if_changed_dep,link-vmlinux) targets := vmlinux # The actual objects are generated when descending, # make sure no implicit rule kicks in -$(sort $(vmlinux-deps)): . ; +$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ; filechk_kernel.release = \ echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))" diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 161bca64e8aa..07486f90d5e2 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -214,9 +214,6 @@ if [ "$1" = "clean" ]; then exit 0 fi -#link vmlinux.o -${MAKE} -f "${srctree}/scripts/Makefile.vmlinux_o" - # modpost vmlinux.o to check for section mismatches ${MAKE} -f "${srctree}/scripts/Makefile.modpost" MODPOST_VMLINUX=1 -- cgit v1.2.3-59-g8ed1b From f73edc8951b2de515b5ecc8a357ccd47dd41077e Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 25 Sep 2022 03:19:13 +0900 Subject: kbuild: unify two modpost invocations Currently, modpost is executed twice; first for vmlinux, second for modules. This commit merges them. Current build flow ================== 1) build obj-y and obj-m objects 2) link vmlinux.o 3) modpost for vmlinux 4) link vmlinux 5) modpost for modules 6) link modules (*.ko) The build steps 1) through 6) are serialized, that is, modules are built after vmlinux. You do not get benefits of parallel builds when scripts/link-vmlinux.sh is being run. New build flow ============== 1) build obj-y and obj-m objects 2) link vmlinux.o 3) modpost for vmlinux and modules 4a) link vmlinux 4b) link modules (*.ko) In the new build flow, modpost is invoked just once. vmlinux and modules are built in parallel. One exception is CONFIG_DEBUG_INFO_BTF_MODULES=y, where modules depend on vmlinux. Signed-off-by: Masahiro Yamada Tested-by: Nick Desaulniers Reviewed-by: Nicolas Schier --- Makefile | 32 ++++++++++++---- scripts/Makefile.modfinal | 2 +- scripts/Makefile.modpost | 93 ++++++++++++++--------------------------------- scripts/link-vmlinux.sh | 3 -- 4 files changed, 54 insertions(+), 76 deletions(-) (limited to 'scripts') diff --git a/Makefile b/Makefile index 21c41a03d98d..41ab27601bb4 100644 --- a/Makefile +++ b/Makefile @@ -1150,7 +1150,7 @@ cmd_link-vmlinux = \ $(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)"; \ $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true) -vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) FORCE +vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) modpost FORCE +$(call if_changed_dep,link-vmlinux) targets := vmlinux @@ -1426,7 +1426,13 @@ endif # Build modules # -modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_prepare +# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFOBTF_MODULES +# is an exception. +ifdef CONFIG_DEBUG_INFO_BTF_MODULES +modules: vmlinux +endif + +modules: modules_prepare # Target to prepare building external modules modules_prepare: prepare @@ -1739,8 +1745,12 @@ ifdef CONFIG_MODULES $(MODORDER): $(build-dir) @: -modules: modules_check - $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost +# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules. +# This is solely useful to speed up test compiles. +modules: modpost +ifneq ($(KBUILD_MODPOST_NOFINAL),1) + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal +endif PHONY += modules_check modules_check: $(MODORDER) @@ -1771,6 +1781,11 @@ KBUILD_MODULES := endif # CONFIG_MODULES +PHONY += modpost +modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \ + $(if $(KBUILD_MODULES), modules_check) + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost + # Single targets # --------------------------------------------------------------------------- # To build individual files in subdirectories, you can do like this: @@ -1790,16 +1805,19 @@ single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS))) single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \ $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko))) -$(single-ko): single_modpost +$(single-ko): single_modules @: $(single-no-ko): $(build-dir) @: # Remove MODORDER when done because it is not the real one. -PHONY += single_modpost -single_modpost: $(single-no-ko) modules_prepare +PHONY += single_modules +single_modules: $(single-no-ko) modules_prepare $(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER) $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost +ifneq ($(KBUILD_MODPOST_NOFINAL),1) + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal +endif $(Q)rm -f $(MODORDER) single-goals := $(addprefix $(build-dir)/, $(single-no-ko)) diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal index 35100e981f4a..a3cf9e3647c9 100644 --- a/scripts/Makefile.modfinal +++ b/scripts/Makefile.modfinal @@ -55,7 +55,7 @@ if_changed_except = $(if $(call newer_prereqs_except,$(2))$(cmd-check), \ printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:) # Re-generate module BTFs if either module's .ko or vmlinux changed -$(modules): %.ko: %.o %.mod.o scripts/module.lds $(if $(KBUILD_BUILTIN),vmlinux) FORCE +$(modules): %.ko: %.o %.mod.o scripts/module.lds $(and $(CONFIG_DEBUG_INFO_BTF_MODULES),$(KBUILD_BUILTIN),vmlinux) FORCE +$(call if_changed_except,ld_ko_o,vmlinux) ifdef CONFIG_DEBUG_INFO_BTF_MODULES +$(if $(newer-prereqs),$(call cmd,btf_ko)) diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index 04ad00917b2f..2daf760eeb25 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -32,9 +32,6 @@ # Step 4 is solely used to allow module versioning in external modules, # where the CRC of each module is retrieved from the Module.symvers file. -# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules. -# This is solely useful to speed up test compiles - PHONY := __modpost __modpost: @@ -45,24 +42,23 @@ MODPOST = scripts/mod/modpost \ $(if $(CONFIG_MODVERSIONS),-m) \ $(if $(CONFIG_MODULE_SRCVERSION_ALL),-a) \ $(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \ + $(if $(KBUILD_NSDEPS),-d $(MODULES_NSDEPS)) \ + $(if $(CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS)$(KBUILD_NSDEPS),-N) \ -o $@ -ifdef MODPOST_VMLINUX - -quiet_cmd_modpost = MODPOST $@ - cmd_modpost = $(MODPOST) $< - -vmlinux.symvers: vmlinux.o - $(call cmd,modpost) +# 'make -i -k' ignores compile errors, and builds as many modules as possible. +ifneq ($(findstring i,$(filter-out --%,$(MAKEFLAGS))),) +MODPOST += -n +endif -__modpost: vmlinux.symvers +ifeq ($(KBUILD_EXTMOD),) # Generate the list of in-tree objects in vmlinux # --------------------------------------------------------------------------- # This is used to retrieve symbol versions generated by genksyms. ifdef CONFIG_MODVERSIONS -vmlinux.symvers: .vmlinux.objs +vmlinux.symvers Module.symvers: .vmlinux.objs endif # Ignore libgcc.a @@ -83,24 +79,12 @@ targets += .vmlinux.objs .vmlinux.objs: $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS) FORCE $(call if_changed,vmlinux_objs) -else - -ifeq ($(KBUILD_EXTMOD),) - -input-symdump := vmlinux.symvers -output-symdump := modules-only.symvers - -quiet_cmd_cat = GEN $@ - cmd_cat = cat $(real-prereqs) > $@ - -ifneq ($(wildcard vmlinux.symvers),) - -__modpost: Module.symvers -Module.symvers: vmlinux.symvers modules-only.symvers FORCE - $(call if_changed,cat) - -targets += Module.symvers +vmlinux.o-if-present := $(wildcard vmlinux.o) +output-symdump := vmlinux.symvers +ifdef KBUILD_MODULES +output-symdump := $(if $(vmlinux.o-if-present), Module.symvers, modules-only.symvers) +missing-input := $(filter-out $(vmlinux.o-if-present),vmlinux.o) endif else @@ -112,56 +96,35 @@ src := $(obj) # Include the module's Makefile to find KBUILD_EXTRA_SYMBOLS include $(or $(wildcard $(src)/Kbuild), $(src)/Makefile) -# modpost option for external modules -MODPOST += -e - -input-symdump := Module.symvers $(KBUILD_EXTRA_SYMBOLS) +module.symvers-if-present := $(wildcard Module.symvers) output-symdump := $(KBUILD_EXTMOD)/Module.symvers +missing-input := $(filter-out $(module.symvers-if-present), Module.symvers) -endif - -existing-input-symdump := $(wildcard $(input-symdump)) - -# modpost options for modules (both in-kernel and external) -MODPOST += \ - $(addprefix -i ,$(existing-input-symdump)) \ - $(if $(KBUILD_NSDEPS),-d $(MODULES_NSDEPS)) \ - $(if $(CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS)$(KBUILD_NSDEPS),-N) - -# 'make -i -k' ignores compile errors, and builds as many modules as possible. -ifneq ($(findstring i,$(filter-out --%,$(MAKEFLAGS))),) -MODPOST += -n -endif +MODPOST += -e $(addprefix -i ,$(module.symvers-if-present) $(KBUILD_EXTRA_SYMBOLS)) -# Clear VPATH to not search for *.symvers in $(srctree). Check only $(objtree). -VPATH := -$(input-symdump): - @echo >&2 'WARNING: Symbol version dump "$@" is missing.' - @echo >&2 ' Modules may not have dependencies or modversions.' - @echo >&2 ' You may get many unresolved symbol warnings.' +endif # ($(KBUILD_EXTMOD),) -# KBUILD_MODPOST_WARN can be set to avoid error out in case of undefined symbols -ifneq ($(KBUILD_MODPOST_WARN)$(filter-out $(existing-input-symdump), $(input-symdump)),) +ifneq ($(KBUILD_MODPOST_WARN)$(missing-input),) MODPOST += -w endif +modorder-if-needed := $(if $(KBUILD_MODULES), $(MODORDER)) + # Read out modules.order to pass in modpost. # Otherwise, allmodconfig would fail with "Argument list too long". quiet_cmd_modpost = MODPOST $@ - cmd_modpost = sed 's/ko$$/o/' $< | $(MODPOST) -T - - -$(output-symdump): $(MODORDER) $(input-symdump) FORCE - $(call if_changed,modpost) + cmd_modpost = \ + $(if $(missing-input), \ + echo >&2 "WARNING: $(missing-input) is missing."; \ + echo >&2 " Modules may not have dependencies or modversions."; \ + echo >&2 " You may get many unresolved symbol warnings.";) \ + sed 's/ko$$/o/' $(or $(modorder-if-needed), /dev/null) | $(MODPOST) $(vmlinux.o-if-present) -T - targets += $(output-symdump) +$(output-symdump): $(modorder-if-needed) $(vmlinux.o-if-present) $(moudle.symvers-if-present) FORCE + $(call if_changed,modpost) __modpost: $(output-symdump) -ifneq ($(KBUILD_MODPOST_NOFINAL),1) - $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal -endif - -endif - PHONY += FORCE FORCE: diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 07486f90d5e2..6a197d8a88ac 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -214,9 +214,6 @@ if [ "$1" = "clean" ]; then exit 0 fi -# modpost vmlinux.o to check for section mismatches -${MAKE} -f "${srctree}/scripts/Makefile.modpost" MODPOST_VMLINUX=1 - info MODINFO modules.builtin.modinfo ${OBJCOPY} -j .modinfo -O binary vmlinux.o modules.builtin.modinfo info GEN modules.builtin -- cgit v1.2.3-59-g8ed1b From 425937381ec492d454cd4d8ba594711331128a44 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 15 Sep 2022 15:26:23 +0900 Subject: kbuild: re-run modpost when it is updated Modpost generates .vmlinux.export.c and *.mod.c, which are prerequisites of vmlinux and modules, respectively. The modpost stage should be re-run when the modpost code is updated. Signed-off-by: Masahiro Yamada --- scripts/Makefile.modpost | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) (limited to 'scripts') diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index 2daf760eeb25..40a3e9b0512b 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -38,7 +38,7 @@ __modpost: include include/config/auto.conf include $(srctree)/scripts/Kbuild.include -MODPOST = scripts/mod/modpost \ +modpost-args = \ $(if $(CONFIG_MODVERSIONS),-m) \ $(if $(CONFIG_MODULE_SRCVERSION_ALL),-a) \ $(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \ @@ -48,7 +48,7 @@ MODPOST = scripts/mod/modpost \ # 'make -i -k' ignores compile errors, and builds as many modules as possible. ifneq ($(findstring i,$(filter-out --%,$(MAKEFLAGS))),) -MODPOST += -n +modpost-args += -n endif ifeq ($(KBUILD_EXTMOD),) @@ -100,16 +100,18 @@ module.symvers-if-present := $(wildcard Module.symvers) output-symdump := $(KBUILD_EXTMOD)/Module.symvers missing-input := $(filter-out $(module.symvers-if-present), Module.symvers) -MODPOST += -e $(addprefix -i ,$(module.symvers-if-present) $(KBUILD_EXTRA_SYMBOLS)) +modpost-args += -e $(addprefix -i ,$(module.symvers-if-present) $(KBUILD_EXTRA_SYMBOLS)) endif # ($(KBUILD_EXTMOD),) ifneq ($(KBUILD_MODPOST_WARN)$(missing-input),) -MODPOST += -w +modpost-args += -w endif modorder-if-needed := $(if $(KBUILD_MODULES), $(MODORDER)) +MODPOST = scripts/mod/modpost + # Read out modules.order to pass in modpost. # Otherwise, allmodconfig would fail with "Argument list too long". quiet_cmd_modpost = MODPOST $@ @@ -118,10 +120,10 @@ quiet_cmd_modpost = MODPOST $@ echo >&2 "WARNING: $(missing-input) is missing."; \ echo >&2 " Modules may not have dependencies or modversions."; \ echo >&2 " You may get many unresolved symbol warnings.";) \ - sed 's/ko$$/o/' $(or $(modorder-if-needed), /dev/null) | $(MODPOST) $(vmlinux.o-if-present) -T - + sed 's/ko$$/o/' $(or $(modorder-if-needed), /dev/null) | $(MODPOST) $(modpost-args) $(vmlinux.o-if-present) -T - targets += $(output-symdump) -$(output-symdump): $(modorder-if-needed) $(vmlinux.o-if-present) $(moudle.symvers-if-present) FORCE +$(output-symdump): $(modorder-if-needed) $(vmlinux.o-if-present) $(moudle.symvers-if-present) $(MODPOST) FORCE $(call if_changed,modpost) __modpost: $(output-symdump) -- cgit v1.2.3-59-g8ed1b From f4bf1cd4ac9c8c4610b687e49a1ba691ab286235 Mon Sep 17 00:00:00 2001 From: Jonathan Corbet Date: Tue, 27 Sep 2022 10:05:57 -0600 Subject: docs: move asm-annotations.rst into core-api This one file should not really be in the top-level documentation directory. core-api/ may not be a perfect fit but seems to be best, so move it there. Adjust a couple of internal document references to make them location-independent, and point checkpatch.pl at the new location. Cc: Jiri Slaby Cc: Joe Perches Reviewed-by: David Vernet Acked-by: Jani Nikula Signed-off-by: Jonathan Corbet Acked-by: Randy Dunlap Link: https://lore.kernel.org/r/20220927160559.97154-6-corbet@lwn.net Signed-off-by: Jonathan Corbet --- Documentation/asm-annotations.rst | 221 ---------------------------- Documentation/core-api/asm-annotations.rst | 222 +++++++++++++++++++++++++++++ Documentation/core-api/index.rst | 1 + Documentation/index.rst | 8 -- scripts/checkpatch.pl | 2 +- 5 files changed, 224 insertions(+), 230 deletions(-) delete mode 100644 Documentation/asm-annotations.rst create mode 100644 Documentation/core-api/asm-annotations.rst (limited to 'scripts') diff --git a/Documentation/asm-annotations.rst b/Documentation/asm-annotations.rst deleted file mode 100644 index a64f2ca469d4..000000000000 --- a/Documentation/asm-annotations.rst +++ /dev/null @@ -1,221 +0,0 @@ -Assembler Annotations -===================== - -Copyright (c) 2017-2019 Jiri Slaby - -This document describes the new macros for annotation of data and code in -assembly. In particular, it contains information about ``SYM_FUNC_START``, -``SYM_FUNC_END``, ``SYM_CODE_START``, and similar. - -Rationale ---------- -Some code like entries, trampolines, or boot code needs to be written in -assembly. The same as in C, such code is grouped into functions and -accompanied with data. Standard assemblers do not force users into precisely -marking these pieces as code, data, or even specifying their length. -Nevertheless, assemblers provide developers with such annotations to aid -debuggers throughout assembly. On top of that, developers also want to mark -some functions as *global* in order to be visible outside of their translation -units. - -Over time, the Linux kernel has adopted macros from various projects (like -``binutils``) to facilitate such annotations. So for historic reasons, -developers have been using ``ENTRY``, ``END``, ``ENDPROC``, and other -annotations in assembly. Due to the lack of their documentation, the macros -are used in rather wrong contexts at some locations. Clearly, ``ENTRY`` was -intended to denote the beginning of global symbols (be it data or code). -``END`` used to mark the end of data or end of special functions with -*non-standard* calling convention. In contrast, ``ENDPROC`` should annotate -only ends of *standard* functions. - -When these macros are used correctly, they help assemblers generate a nice -object with both sizes and types set correctly. For example, the result of -``arch/x86/lib/putuser.S``:: - - Num: Value Size Type Bind Vis Ndx Name - 25: 0000000000000000 33 FUNC GLOBAL DEFAULT 1 __put_user_1 - 29: 0000000000000030 37 FUNC GLOBAL DEFAULT 1 __put_user_2 - 32: 0000000000000060 36 FUNC GLOBAL DEFAULT 1 __put_user_4 - 35: 0000000000000090 37 FUNC GLOBAL DEFAULT 1 __put_user_8 - -This is not only important for debugging purposes. When there are properly -annotated objects like this, tools can be run on them to generate more useful -information. In particular, on properly annotated objects, ``objtool`` can be -run to check and fix the object if needed. Currently, ``objtool`` can report -missing frame pointer setup/destruction in functions. It can also -automatically generate annotations for :doc:`ORC unwinder ` -for most code. Both of these are especially important to support reliable -stack traces which are in turn necessary for :doc:`Kernel live patching -`. - -Caveat and Discussion ---------------------- -As one might realize, there were only three macros previously. That is indeed -insufficient to cover all the combinations of cases: - -* standard/non-standard function -* code/data -* global/local symbol - -There was a discussion_ and instead of extending the current ``ENTRY/END*`` -macros, it was decided that brand new macros should be introduced instead:: - - So how about using macro names that actually show the purpose, instead - of importing all the crappy, historic, essentially randomly chosen - debug symbol macro names from the binutils and older kernels? - -.. _discussion: https://lore.kernel.org/r/20170217104757.28588-1-jslaby@suse.cz - -Macros Description ------------------- - -The new macros are prefixed with the ``SYM_`` prefix and can be divided into -three main groups: - -1. ``SYM_FUNC_*`` -- to annotate C-like functions. This means functions with - standard C calling conventions. For example, on x86, this means that the - stack contains a return address at the predefined place and a return from - the function can happen in a standard way. When frame pointers are enabled, - save/restore of frame pointer shall happen at the start/end of a function, - respectively, too. - - Checking tools like ``objtool`` should ensure such marked functions conform - to these rules. The tools can also easily annotate these functions with - debugging information (like *ORC data*) automatically. - -2. ``SYM_CODE_*`` -- special functions called with special stack. Be it - interrupt handlers with special stack content, trampolines, or startup - functions. - - Checking tools mostly ignore checking of these functions. But some debug - information still can be generated automatically. For correct debug data, - this code needs hints like ``UNWIND_HINT_REGS`` provided by developers. - -3. ``SYM_DATA*`` -- obviously data belonging to ``.data`` sections and not to - ``.text``. Data do not contain instructions, so they have to be treated - specially by the tools: they should not treat the bytes as instructions, - nor assign any debug information to them. - -Instruction Macros -~~~~~~~~~~~~~~~~~~ -This section covers ``SYM_FUNC_*`` and ``SYM_CODE_*`` enumerated above. - -``objtool`` requires that all code must be contained in an ELF symbol. Symbol -names that have a ``.L`` prefix do not emit symbol table entries. ``.L`` -prefixed symbols can be used within a code region, but should be avoided for -denoting a range of code via ``SYM_*_START/END`` annotations. - -* ``SYM_FUNC_START`` and ``SYM_FUNC_START_LOCAL`` are supposed to be **the - most frequent markings**. They are used for functions with standard calling - conventions -- global and local. Like in C, they both align the functions to - architecture specific ``__ALIGN`` bytes. There are also ``_NOALIGN`` variants - for special cases where developers do not want this implicit alignment. - - ``SYM_FUNC_START_WEAK`` and ``SYM_FUNC_START_WEAK_NOALIGN`` markings are - also offered as an assembler counterpart to the *weak* attribute known from - C. - - All of these **shall** be coupled with ``SYM_FUNC_END``. First, it marks - the sequence of instructions as a function and computes its size to the - generated object file. Second, it also eases checking and processing such - object files as the tools can trivially find exact function boundaries. - - So in most cases, developers should write something like in the following - example, having some asm instructions in between the macros, of course:: - - SYM_FUNC_START(memset) - ... asm insns ... - SYM_FUNC_END(memset) - - In fact, this kind of annotation corresponds to the now deprecated ``ENTRY`` - and ``ENDPROC`` macros. - -* ``SYM_FUNC_ALIAS``, ``SYM_FUNC_ALIAS_LOCAL``, and ``SYM_FUNC_ALIAS_WEAK`` can - be used to define multiple names for a function. The typical use is:: - - SYM_FUNC_START(__memset) - ... asm insns ... - SYN_FUNC_END(__memset) - SYM_FUNC_ALIAS(memset, __memset) - - In this example, one can call ``__memset`` or ``memset`` with the same - result, except the debug information for the instructions is generated to - the object file only once -- for the non-``ALIAS`` case. - -* ``SYM_CODE_START`` and ``SYM_CODE_START_LOCAL`` should be used only in - special cases -- if you know what you are doing. This is used exclusively - for interrupt handlers and similar where the calling convention is not the C - one. ``_NOALIGN`` variants exist too. The use is the same as for the ``FUNC`` - category above:: - - SYM_CODE_START_LOCAL(bad_put_user) - ... asm insns ... - SYM_CODE_END(bad_put_user) - - Again, every ``SYM_CODE_START*`` **shall** be coupled by ``SYM_CODE_END``. - - To some extent, this category corresponds to deprecated ``ENTRY`` and - ``END``. Except ``END`` had several other meanings too. - -* ``SYM_INNER_LABEL*`` is used to denote a label inside some - ``SYM_{CODE,FUNC}_START`` and ``SYM_{CODE,FUNC}_END``. They are very similar - to C labels, except they can be made global. An example of use:: - - SYM_CODE_START(ftrace_caller) - /* save_mcount_regs fills in first two parameters */ - ... - - SYM_INNER_LABEL(ftrace_caller_op_ptr, SYM_L_GLOBAL) - /* Load the ftrace_ops into the 3rd parameter */ - ... - - SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL) - call ftrace_stub - ... - retq - SYM_CODE_END(ftrace_caller) - -Data Macros -~~~~~~~~~~~ -Similar to instructions, there is a couple of macros to describe data in the -assembly. - -* ``SYM_DATA_START`` and ``SYM_DATA_START_LOCAL`` mark the start of some data - and shall be used in conjunction with either ``SYM_DATA_END``, or - ``SYM_DATA_END_LABEL``. The latter adds also a label to the end, so that - people can use ``lstack`` and (local) ``lstack_end`` in the following - example:: - - SYM_DATA_START_LOCAL(lstack) - .skip 4096 - SYM_DATA_END_LABEL(lstack, SYM_L_LOCAL, lstack_end) - -* ``SYM_DATA`` and ``SYM_DATA_LOCAL`` are variants for simple, mostly one-line - data:: - - SYM_DATA(HEAP, .long rm_heap) - SYM_DATA(heap_end, .long rm_stack) - - In the end, they expand to ``SYM_DATA_START`` with ``SYM_DATA_END`` - internally. - -Support Macros -~~~~~~~~~~~~~~ -All the above reduce themselves to some invocation of ``SYM_START``, -``SYM_END``, or ``SYM_ENTRY`` at last. Normally, developers should avoid using -these. - -Further, in the above examples, one could see ``SYM_L_LOCAL``. There are also -``SYM_L_GLOBAL`` and ``SYM_L_WEAK``. All are intended to denote linkage of a -symbol marked by them. They are used either in ``_LABEL`` variants of the -earlier macros, or in ``SYM_START``. - - -Overriding Macros -~~~~~~~~~~~~~~~~~ -Architecture can also override any of the macros in their own -``asm/linkage.h``, including macros specifying the type of a symbol -(``SYM_T_FUNC``, ``SYM_T_OBJECT``, and ``SYM_T_NONE``). As every macro -described in this file is surrounded by ``#ifdef`` + ``#endif``, it is enough -to define the macros differently in the aforementioned architecture-dependent -header. diff --git a/Documentation/core-api/asm-annotations.rst b/Documentation/core-api/asm-annotations.rst new file mode 100644 index 000000000000..bc514ed59887 --- /dev/null +++ b/Documentation/core-api/asm-annotations.rst @@ -0,0 +1,222 @@ +Assembler Annotations +===================== + +Copyright (c) 2017-2019 Jiri Slaby + +This document describes the new macros for annotation of data and code in +assembly. In particular, it contains information about ``SYM_FUNC_START``, +``SYM_FUNC_END``, ``SYM_CODE_START``, and similar. + +Rationale +--------- +Some code like entries, trampolines, or boot code needs to be written in +assembly. The same as in C, such code is grouped into functions and +accompanied with data. Standard assemblers do not force users into precisely +marking these pieces as code, data, or even specifying their length. +Nevertheless, assemblers provide developers with such annotations to aid +debuggers throughout assembly. On top of that, developers also want to mark +some functions as *global* in order to be visible outside of their translation +units. + +Over time, the Linux kernel has adopted macros from various projects (like +``binutils``) to facilitate such annotations. So for historic reasons, +developers have been using ``ENTRY``, ``END``, ``ENDPROC``, and other +annotations in assembly. Due to the lack of their documentation, the macros +are used in rather wrong contexts at some locations. Clearly, ``ENTRY`` was +intended to denote the beginning of global symbols (be it data or code). +``END`` used to mark the end of data or end of special functions with +*non-standard* calling convention. In contrast, ``ENDPROC`` should annotate +only ends of *standard* functions. + +When these macros are used correctly, they help assemblers generate a nice +object with both sizes and types set correctly. For example, the result of +``arch/x86/lib/putuser.S``:: + + Num: Value Size Type Bind Vis Ndx Name + 25: 0000000000000000 33 FUNC GLOBAL DEFAULT 1 __put_user_1 + 29: 0000000000000030 37 FUNC GLOBAL DEFAULT 1 __put_user_2 + 32: 0000000000000060 36 FUNC GLOBAL DEFAULT 1 __put_user_4 + 35: 0000000000000090 37 FUNC GLOBAL DEFAULT 1 __put_user_8 + +This is not only important for debugging purposes. When there are properly +annotated objects like this, tools can be run on them to generate more useful +information. In particular, on properly annotated objects, ``objtool`` can be +run to check and fix the object if needed. Currently, ``objtool`` can report +missing frame pointer setup/destruction in functions. It can also +automatically generate annotations for the ORC unwinder +(Documentation/x86/orc-unwinder.rst) +for most code. Both of these are especially important to support reliable +stack traces which are in turn necessary for kernel live patching +(Documentation/livepatch/livepatch.rst). + +Caveat and Discussion +--------------------- +As one might realize, there were only three macros previously. That is indeed +insufficient to cover all the combinations of cases: + +* standard/non-standard function +* code/data +* global/local symbol + +There was a discussion_ and instead of extending the current ``ENTRY/END*`` +macros, it was decided that brand new macros should be introduced instead:: + + So how about using macro names that actually show the purpose, instead + of importing all the crappy, historic, essentially randomly chosen + debug symbol macro names from the binutils and older kernels? + +.. _discussion: https://lore.kernel.org/r/20170217104757.28588-1-jslaby@suse.cz + +Macros Description +------------------ + +The new macros are prefixed with the ``SYM_`` prefix and can be divided into +three main groups: + +1. ``SYM_FUNC_*`` -- to annotate C-like functions. This means functions with + standard C calling conventions. For example, on x86, this means that the + stack contains a return address at the predefined place and a return from + the function can happen in a standard way. When frame pointers are enabled, + save/restore of frame pointer shall happen at the start/end of a function, + respectively, too. + + Checking tools like ``objtool`` should ensure such marked functions conform + to these rules. The tools can also easily annotate these functions with + debugging information (like *ORC data*) automatically. + +2. ``SYM_CODE_*`` -- special functions called with special stack. Be it + interrupt handlers with special stack content, trampolines, or startup + functions. + + Checking tools mostly ignore checking of these functions. But some debug + information still can be generated automatically. For correct debug data, + this code needs hints like ``UNWIND_HINT_REGS`` provided by developers. + +3. ``SYM_DATA*`` -- obviously data belonging to ``.data`` sections and not to + ``.text``. Data do not contain instructions, so they have to be treated + specially by the tools: they should not treat the bytes as instructions, + nor assign any debug information to them. + +Instruction Macros +~~~~~~~~~~~~~~~~~~ +This section covers ``SYM_FUNC_*`` and ``SYM_CODE_*`` enumerated above. + +``objtool`` requires that all code must be contained in an ELF symbol. Symbol +names that have a ``.L`` prefix do not emit symbol table entries. ``.L`` +prefixed symbols can be used within a code region, but should be avoided for +denoting a range of code via ``SYM_*_START/END`` annotations. + +* ``SYM_FUNC_START`` and ``SYM_FUNC_START_LOCAL`` are supposed to be **the + most frequent markings**. They are used for functions with standard calling + conventions -- global and local. Like in C, they both align the functions to + architecture specific ``__ALIGN`` bytes. There are also ``_NOALIGN`` variants + for special cases where developers do not want this implicit alignment. + + ``SYM_FUNC_START_WEAK`` and ``SYM_FUNC_START_WEAK_NOALIGN`` markings are + also offered as an assembler counterpart to the *weak* attribute known from + C. + + All of these **shall** be coupled with ``SYM_FUNC_END``. First, it marks + the sequence of instructions as a function and computes its size to the + generated object file. Second, it also eases checking and processing such + object files as the tools can trivially find exact function boundaries. + + So in most cases, developers should write something like in the following + example, having some asm instructions in between the macros, of course:: + + SYM_FUNC_START(memset) + ... asm insns ... + SYM_FUNC_END(memset) + + In fact, this kind of annotation corresponds to the now deprecated ``ENTRY`` + and ``ENDPROC`` macros. + +* ``SYM_FUNC_ALIAS``, ``SYM_FUNC_ALIAS_LOCAL``, and ``SYM_FUNC_ALIAS_WEAK`` can + be used to define multiple names for a function. The typical use is:: + + SYM_FUNC_START(__memset) + ... asm insns ... + SYN_FUNC_END(__memset) + SYM_FUNC_ALIAS(memset, __memset) + + In this example, one can call ``__memset`` or ``memset`` with the same + result, except the debug information for the instructions is generated to + the object file only once -- for the non-``ALIAS`` case. + +* ``SYM_CODE_START`` and ``SYM_CODE_START_LOCAL`` should be used only in + special cases -- if you know what you are doing. This is used exclusively + for interrupt handlers and similar where the calling convention is not the C + one. ``_NOALIGN`` variants exist too. The use is the same as for the ``FUNC`` + category above:: + + SYM_CODE_START_LOCAL(bad_put_user) + ... asm insns ... + SYM_CODE_END(bad_put_user) + + Again, every ``SYM_CODE_START*`` **shall** be coupled by ``SYM_CODE_END``. + + To some extent, this category corresponds to deprecated ``ENTRY`` and + ``END``. Except ``END`` had several other meanings too. + +* ``SYM_INNER_LABEL*`` is used to denote a label inside some + ``SYM_{CODE,FUNC}_START`` and ``SYM_{CODE,FUNC}_END``. They are very similar + to C labels, except they can be made global. An example of use:: + + SYM_CODE_START(ftrace_caller) + /* save_mcount_regs fills in first two parameters */ + ... + + SYM_INNER_LABEL(ftrace_caller_op_ptr, SYM_L_GLOBAL) + /* Load the ftrace_ops into the 3rd parameter */ + ... + + SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL) + call ftrace_stub + ... + retq + SYM_CODE_END(ftrace_caller) + +Data Macros +~~~~~~~~~~~ +Similar to instructions, there is a couple of macros to describe data in the +assembly. + +* ``SYM_DATA_START`` and ``SYM_DATA_START_LOCAL`` mark the start of some data + and shall be used in conjunction with either ``SYM_DATA_END``, or + ``SYM_DATA_END_LABEL``. The latter adds also a label to the end, so that + people can use ``lstack`` and (local) ``lstack_end`` in the following + example:: + + SYM_DATA_START_LOCAL(lstack) + .skip 4096 + SYM_DATA_END_LABEL(lstack, SYM_L_LOCAL, lstack_end) + +* ``SYM_DATA`` and ``SYM_DATA_LOCAL`` are variants for simple, mostly one-line + data:: + + SYM_DATA(HEAP, .long rm_heap) + SYM_DATA(heap_end, .long rm_stack) + + In the end, they expand to ``SYM_DATA_START`` with ``SYM_DATA_END`` + internally. + +Support Macros +~~~~~~~~~~~~~~ +All the above reduce themselves to some invocation of ``SYM_START``, +``SYM_END``, or ``SYM_ENTRY`` at last. Normally, developers should avoid using +these. + +Further, in the above examples, one could see ``SYM_L_LOCAL``. There are also +``SYM_L_GLOBAL`` and ``SYM_L_WEAK``. All are intended to denote linkage of a +symbol marked by them. They are used either in ``_LABEL`` variants of the +earlier macros, or in ``SYM_START``. + + +Overriding Macros +~~~~~~~~~~~~~~~~~ +Architecture can also override any of the macros in their own +``asm/linkage.h``, including macros specifying the type of a symbol +(``SYM_T_FUNC``, ``SYM_T_OBJECT``, and ``SYM_T_NONE``). As every macro +described in this file is surrounded by ``#ifdef`` + ``#endif``, it is enough +to define the macros differently in the aforementioned architecture-dependent +header. diff --git a/Documentation/core-api/index.rst b/Documentation/core-api/index.rst index dc95df462eea..f5d8e3779fe8 100644 --- a/Documentation/core-api/index.rst +++ b/Documentation/core-api/index.rst @@ -23,6 +23,7 @@ it. printk-formats printk-index symbol-namespaces + asm-annotations Data structures and low-level utilities ======================================= diff --git a/Documentation/index.rst b/Documentation/index.rst index da80c584133c..5a700548ae82 100644 --- a/Documentation/index.rst +++ b/Documentation/index.rst @@ -89,14 +89,6 @@ platform firmwares. devicetree/index -Architecture-agnostic documentation ------------------------------------ - -.. toctree:: - :maxdepth: 1 - - asm-annotations - Architecture-specific documentation ----------------------------------- diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 79e759aac543..812af52f97d2 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -3751,7 +3751,7 @@ sub process { if ($realfile =~ /\.S$/ && $line =~ /^\+\s*(?:[A-Z]+_)?SYM_[A-Z]+_(?:START|END)(?:_[A-Z_]+)?\s*\(\s*\.L/) { WARN("AVOID_L_PREFIX", - "Avoid using '.L' prefixed local symbol names for denoting a range of code via 'SYM_*_START/END' annotations; see Documentation/asm-annotations.rst\n" . $herecurr); + "Avoid using '.L' prefixed local symbol names for denoting a range of code via 'SYM_*_START/END' annotations; see Documentation/core-api/asm-annotations.rst\n" . $herecurr); } # check we are in a valid source file C or perl if not then ignore this hunk -- cgit v1.2.3-59-g8ed1b From 69d517e6e21099f81efbd39e47874649ae575804 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Fri, 23 Sep 2022 13:34:25 +0200 Subject: checkpatch: warn on usage of VM_BUG_ON() and other BUG variants checkpatch does not point out that VM_BUG_ON() and friends should be avoided, however, Linus notes: VM_BUG_ON() has the exact same semantics as BUG_ON. It is literally no different, the only difference is "we can make the code smaller because these are less important". [1] So let's warn on VM_BUG_ON() and other BUG variants as well. While at it, make it clearer that the kernel really shouldn't be crashed. As there are some subsystem BUG macros that actually don't end up crashing the kernel -- for example, KVM_BUG_ON() -- exclude these manually. [1] https://lore.kernel.org/r/CAHk-=wg40EAZofO16Eviaj7mfqDhZ2gVEbvfsMf6gYzspRjYvw@mail.gmail.com Signed-off-by: David Hildenbrand Link: https://lore.kernel.org/r/20220923113426.52871-3-david@redhat.com Signed-off-by: Jonathan Corbet --- scripts/checkpatch.pl | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'scripts') diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 812af52f97d2..4aa09e0cb86a 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -4695,12 +4695,12 @@ sub process { } } -# avoid BUG() or BUG_ON() - if ($line =~ /\b(?:BUG|BUG_ON)\b/) { +# do not use BUG() or variants + if ($line =~ /\b(?!AA_|BUILD_|DCCP_|IDA_|KVM_|RWLOCK_|snd_|SPIN_)(?:[a-zA-Z_]*_)?BUG(?:_ON)?(?:_[A-Z_]+)?\s*\(/) { my $msg_level = \&WARN; $msg_level = \&CHK if ($file); &{$msg_level}("AVOID_BUG", - "Avoid crashing the kernel - try using WARN_ON & recovery code rather than BUG() or BUG_ON()\n" . $herecurr); + "Do not crash the kernel unless it is absolutely unavoidable--use WARN_ON_ONCE() plus recovery code (if feasible) instead of BUG() or variants\n" . $herecurr); } # avoid LINUX_VERSION_CODE -- cgit v1.2.3-59-g8ed1b From 2120635108b35ecad9c59c8b44f6cbdf4f98214e Mon Sep 17 00:00:00 2001 From: Sami Tolvanen Date: Fri, 30 Sep 2022 20:33:10 +0000 Subject: Makefile.extrawarn: Move -Wcast-function-type-strict to W=1 We enable -Wcast-function-type globally in the kernel to warn about mismatching types in function pointer casts. Compilers currently warn only about ABI incompability with this flag, but Clang 16 will enable a stricter version of the check by default that checks for an exact type match. This will be very noisy in the kernel, so disable -Wcast-function-type-strict without W=1 until the new warnings have been addressed. Cc: stable@vger.kernel.org Link: https://reviews.llvm.org/D134831 Link: https://github.com/ClangBuiltLinux/linux/issues/1724 Suggested-by: Nathan Chancellor Signed-off-by: Sami Tolvanen Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20220930203310.4010564-1-samitolvanen@google.com --- scripts/Makefile.extrawarn | 1 + 1 file changed, 1 insertion(+) (limited to 'scripts') diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn index 0621c39a3955..20df48637373 100644 --- a/scripts/Makefile.extrawarn +++ b/scripts/Makefile.extrawarn @@ -52,6 +52,7 @@ KBUILD_CFLAGS += -Wno-sign-compare KBUILD_CFLAGS += $(call cc-disable-warning, pointer-to-enum-cast) KBUILD_CFLAGS += -Wno-tautological-constant-out-of-range-compare KBUILD_CFLAGS += $(call cc-disable-warning, unaligned-access) +KBUILD_CFLAGS += $(call cc-disable-warning, cast-function-type-strict) endif endif -- cgit v1.2.3-59-g8ed1b From 3216484550610470013b7ce1c9ed272da0a74589 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 25 Sep 2022 03:19:14 +0900 Subject: kbuild: use obj-y instead extra-y for objects placed at the head The objects placed at the head of vmlinux need special treatments: - arch/$(SRCARCH)/Makefile adds them to head-y in order to place them before other archives in the linker command line. - arch/$(SRCARCH)/kernel/Makefile adds them to extra-y instead of obj-y to avoid them going into built-in.a. This commit gets rid of the latter. Create vmlinux.a to collect all the objects that are unconditionally linked to vmlinux. The objects listed in head-y are moved to the head of vmlinux.a by using 'ar m'. With this, arch/$(SRCARCH)/kernel/Makefile can consistently use obj-y for builtin objects. There is no *.o that is directly linked to vmlinux. Drop unneeded code in scripts/clang-tools/gen_compile_commands.py. $(AR) mPi needs 'T' to workaround the llvm-ar bug. The fix was suggested by Nathan Chancellor [1]. [1]: https://lore.kernel.org/llvm/YyjjT5gQ2hGMH0ni@dev-arch.thelio-3990X/ Signed-off-by: Masahiro Yamada Tested-by: Nick Desaulniers Reviewed-by: Nicolas Schier --- Documentation/kbuild/makefiles.rst | 18 +----------------- Makefile | 23 ++++++++++++++++++----- arch/alpha/kernel/Makefile | 4 ++-- arch/arc/kernel/Makefile | 4 ++-- arch/arm/kernel/Makefile | 4 ++-- arch/arm64/kernel/Makefile | 4 ++-- arch/csky/kernel/Makefile | 4 ++-- arch/hexagon/kernel/Makefile | 3 ++- arch/ia64/kernel/Makefile | 4 ++-- arch/loongarch/kernel/Makefile | 4 ++-- arch/m68k/68000/Makefile | 2 +- arch/m68k/coldfire/Makefile | 2 +- arch/m68k/kernel/Makefile | 23 ++++++++++++----------- arch/microblaze/kernel/Makefile | 4 ++-- arch/mips/kernel/Makefile | 4 ++-- arch/nios2/kernel/Makefile | 2 +- arch/openrisc/kernel/Makefile | 4 ++-- arch/parisc/kernel/Makefile | 4 ++-- arch/powerpc/kernel/Makefile | 20 ++++++++++---------- arch/riscv/kernel/Makefile | 2 +- arch/s390/kernel/Makefile | 4 ++-- arch/sh/kernel/Makefile | 4 ++-- arch/sparc/kernel/Makefile | 3 +-- arch/x86/kernel/Makefile | 10 +++++----- arch/xtensa/kernel/Makefile | 4 ++-- scripts/Makefile.modpost | 5 ++--- scripts/Makefile.vmlinux_o | 6 +++--- scripts/clang-tools/gen_compile_commands.py | 19 +------------------ scripts/link-vmlinux.sh | 10 ++++------ 29 files changed, 91 insertions(+), 113 deletions(-) (limited to 'scripts') diff --git a/Documentation/kbuild/makefiles.rst b/Documentation/kbuild/makefiles.rst index ee7e3ea1fbe1..5a6a8426cc97 100644 --- a/Documentation/kbuild/makefiles.rst +++ b/Documentation/kbuild/makefiles.rst @@ -340,19 +340,7 @@ more details, with real examples. Examples are: - 1) head objects - - Some objects must be placed at the head of vmlinux. They are - directly linked to vmlinux without going through built-in.a - A typical use-case is an object that contains the entry point. - - arch/$(SRCARCH)/Makefile should specify such objects as head-y. - - Discussion: - Given that we can control the section order in the linker script, - why do we need head-y? - - 2) vmlinux linker script + 1) vmlinux linker script The linker script for vmlinux is located at arch/$(SRCARCH)/kernel/vmlinux.lds @@ -360,10 +348,6 @@ more details, with real examples. Example:: # arch/x86/kernel/Makefile - extra-y := head_$(BITS).o - extra-y += head$(BITS).o - extra-y += ebda.o - extra-y += platform-quirks.o extra-y += vmlinux.lds $(extra-y) should only contain targets needed for vmlinux. diff --git a/Makefile b/Makefile index 22a956b9ffe4..8da45f76ec31 100644 --- a/Makefile +++ b/Makefile @@ -645,6 +645,8 @@ else __all: modules endif +targets := + # Decide whether to build built-in, modular, or both. # Normally, just do built-in. @@ -1107,7 +1109,7 @@ export ARCH_LIB := $(filter %/, $(libs-y)) export ARCH_DRIVERS := $(drivers-y) $(drivers-m) # Externally visible symbols (used by link-vmlinux.sh) -KBUILD_VMLINUX_OBJS := $(head-y) ./built-in.a +KBUILD_VMLINUX_OBJS := ./built-in.a ifdef CONFIG_MODULES KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y))) KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y)) @@ -1115,7 +1117,7 @@ else KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y)) endif -export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS +export KBUILD_VMLINUX_LIBS export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds # Recurse until adjust_autoksyms.sh is satisfied @@ -1140,7 +1142,18 @@ quiet_cmd_autoksyms_h = GEN $@ $(autoksyms_h): $(call cmd,autoksyms_h) -vmlinux.o: autoksyms_recursive $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS) FORCE +# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14 +quiet_cmd_ar_vmlinux.a = AR $@ + cmd_ar_vmlinux.a = \ + rm -f $@; \ + $(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \ + $(AR) mPiT $$($(AR) t $@ | head -n1) $@ $(head-y) + +targets += vmlinux.a +vmlinux.a: $(KBUILD_VMLINUX_OBJS) autoksyms_recursive FORCE + $(call if_changed,ar_vmlinux.a) + +vmlinux.o: vmlinux.a $(KBUILD_VMLINUX_LIBS) FORCE $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink) @@ -1153,7 +1166,7 @@ cmd_link-vmlinux = \ vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) modpost FORCE +$(call if_changed_dep,link-vmlinux) -targets := vmlinux +targets += vmlinux # The actual objects are generated when descending, # make sure no implicit rule kicks in @@ -1878,7 +1891,7 @@ quiet_cmd_gen_compile_commands = GEN $@ cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs)) $(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \ - $(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \ + $(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \ $(if $(CONFIG_MODULES), $(MODORDER)) FORCE $(call if_changed,gen_compile_commands) diff --git a/arch/alpha/kernel/Makefile b/arch/alpha/kernel/Makefile index 5a74581bf0ee..5a5b0a8b7c6a 100644 --- a/arch/alpha/kernel/Makefile +++ b/arch/alpha/kernel/Makefile @@ -3,11 +3,11 @@ # Makefile for the linux kernel. # -extra-y := head.o vmlinux.lds +extra-y := vmlinux.lds asflags-y := $(KBUILD_CFLAGS) ccflags-y := -Wno-sign-compare -obj-y := entry.o traps.o process.o osf_sys.o irq.o \ +obj-y := head.o entry.o traps.o process.o osf_sys.o irq.o \ irq_alpha.o signal.o setup.o ptrace.o time.o \ systbls.o err_common.o io.o bugs.o diff --git a/arch/arc/kernel/Makefile b/arch/arc/kernel/Makefile index 8c4fc4b54c14..0723d888ac44 100644 --- a/arch/arc/kernel/Makefile +++ b/arch/arc/kernel/Makefile @@ -3,7 +3,7 @@ # Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) # -obj-y := arcksyms.o setup.o irq.o reset.o ptrace.o process.o devtree.o +obj-y := head.o arcksyms.o setup.o irq.o reset.o ptrace.o process.o devtree.o obj-y += signal.o traps.o sys.o troubleshoot.o stacktrace.o disasm.o obj-$(CONFIG_ISA_ARCOMPACT) += entry-compact.o intc-compact.o obj-$(CONFIG_ISA_ARCV2) += entry-arcv2.o intc-arcv2.o @@ -31,4 +31,4 @@ else obj-y += ctx_sw_asm.o endif -extra-y := vmlinux.lds head.o +extra-y := vmlinux.lds diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index 553866751e1a..8feaa3217ec5 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -89,7 +89,7 @@ obj-$(CONFIG_VDSO) += vdso.o obj-$(CONFIG_EFI) += efi.o obj-$(CONFIG_PARAVIRT) += paravirt.o -head-y := head$(MMUEXT).o +obj-y += head$(MMUEXT).o obj-$(CONFIG_DEBUG_LL) += debug.o obj-$(CONFIG_EARLY_PRINTK) += early_printk.o obj-$(CONFIG_ARM_PATCH_PHYS_VIRT) += phys2virt.o @@ -109,4 +109,4 @@ obj-$(CONFIG_HAVE_ARM_SMCCC) += smccc-call.o obj-$(CONFIG_GENERIC_CPU_VULNERABILITIES) += spectre.o -extra-y := $(head-y) vmlinux.lds +extra-y := vmlinux.lds diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 1add7b01efa7..b619ff207a57 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -85,8 +85,8 @@ $(obj)/vdso-wrap.o: $(obj)/vdso/vdso.so $(obj)/vdso32-wrap.o: $(obj)/vdso32/vdso.so obj-y += probes/ -head-y := head.o -extra-y += $(head-y) vmlinux.lds +obj-y += head.o +extra-y += vmlinux.lds ifeq ($(CONFIG_DEBUG_EFI),y) AFLAGS_head.o += -DVMLINUX_PATH="\"$(realpath $(objtree)/vmlinux)\"" diff --git a/arch/csky/kernel/Makefile b/arch/csky/kernel/Makefile index 6f14c924b20d..8a868316b912 100644 --- a/arch/csky/kernel/Makefile +++ b/arch/csky/kernel/Makefile @@ -1,7 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only -extra-y := head.o vmlinux.lds +extra-y := vmlinux.lds -obj-y += entry.o atomic.o signal.o traps.o irq.o time.o vdso.o vdso/ +obj-y += head.o entry.o atomic.o signal.o traps.o irq.o time.o vdso.o vdso/ obj-y += power.o syscall.o syscall_table.o setup.o io.o obj-y += process.o cpu-probe.o ptrace.o stacktrace.o obj-y += probes/ diff --git a/arch/hexagon/kernel/Makefile b/arch/hexagon/kernel/Makefile index fae3dce32fde..e73cb321630e 100644 --- a/arch/hexagon/kernel/Makefile +++ b/arch/hexagon/kernel/Makefile @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 -extra-y := head.o vmlinux.lds +extra-y := vmlinux.lds +obj-y += head.o obj-$(CONFIG_SMP) += smp.o obj-y += setup.o irq_cpu.o traps.o syscalltab.o signal.o time.o diff --git a/arch/ia64/kernel/Makefile b/arch/ia64/kernel/Makefile index 08d4a2ba0652..4a1fcb121dda 100644 --- a/arch/ia64/kernel/Makefile +++ b/arch/ia64/kernel/Makefile @@ -7,9 +7,9 @@ ifdef CONFIG_DYNAMIC_FTRACE CFLAGS_REMOVE_ftrace.o = -pg endif -extra-y := head.o vmlinux.lds +extra-y := vmlinux.lds -obj-y := entry.o efi.o efi_stub.o gate-data.o fsys.o irq.o irq_ia64.o \ +obj-y := head.o entry.o efi.o efi_stub.o gate-data.o fsys.o irq.o irq_ia64.o \ irq_lsapic.o ivt.o pal.o patch.o process.o ptrace.o sal.o \ salinfo.o setup.o signal.o sys_ia64.o time.o traps.o unaligned.o \ unwind.o mca.o mca_asm.o topology.o dma-mapping.o iosapic.o acpi.o \ diff --git a/arch/loongarch/kernel/Makefile b/arch/loongarch/kernel/Makefile index e5be17009fe8..6c33b5c45573 100644 --- a/arch/loongarch/kernel/Makefile +++ b/arch/loongarch/kernel/Makefile @@ -3,9 +3,9 @@ # Makefile for the Linux/LoongArch kernel. # -extra-y := head.o vmlinux.lds +extra-y := vmlinux.lds -obj-y += cpu-probe.o cacheinfo.o env.o setup.o entry.o genex.o \ +obj-y += head.o cpu-probe.o cacheinfo.o env.o setup.o entry.o genex.o \ traps.o irq.o idle.o process.o dma.o mem.o io.o reset.o switch.o \ elf.o syscall.o signal.o time.o topology.o inst.o ptrace.o vdso.o diff --git a/arch/m68k/68000/Makefile b/arch/m68k/68000/Makefile index 674541fdf5b8..279560add577 100644 --- a/arch/m68k/68000/Makefile +++ b/arch/m68k/68000/Makefile @@ -17,4 +17,4 @@ obj-$(CONFIG_DRAGEN2) += dragen2.o obj-$(CONFIG_UCSIMM) += ucsimm.o obj-$(CONFIG_UCDIMM) += ucsimm.o -extra-y := head.o +obj-y += head.o diff --git a/arch/m68k/coldfire/Makefile b/arch/m68k/coldfire/Makefile index 9419a6c1f036..c56bc0dc7f2e 100644 --- a/arch/m68k/coldfire/Makefile +++ b/arch/m68k/coldfire/Makefile @@ -45,4 +45,4 @@ obj-$(CONFIG_STMARK2) += stmark2.o obj-$(CONFIG_PCI) += pci.o obj-y += gpio.o -extra-y := head.o +obj-y += head.o diff --git a/arch/m68k/kernel/Makefile b/arch/m68k/kernel/Makefile index c0833da6a2ca..af015447dfb4 100644 --- a/arch/m68k/kernel/Makefile +++ b/arch/m68k/kernel/Makefile @@ -3,19 +3,20 @@ # Makefile for the linux kernel. # -extra-$(CONFIG_AMIGA) := head.o -extra-$(CONFIG_ATARI) := head.o -extra-$(CONFIG_MAC) := head.o -extra-$(CONFIG_APOLLO) := head.o -extra-$(CONFIG_VME) := head.o -extra-$(CONFIG_HP300) := head.o -extra-$(CONFIG_Q40) := head.o -extra-$(CONFIG_SUN3X) := head.o -extra-$(CONFIG_VIRT) := head.o -extra-$(CONFIG_SUN3) := sun3-head.o extra-y += vmlinux.lds -obj-y := entry.o irq.o module.o process.o ptrace.o +obj-$(CONFIG_AMIGA) := head.o +obj-$(CONFIG_ATARI) := head.o +obj-$(CONFIG_MAC) := head.o +obj-$(CONFIG_APOLLO) := head.o +obj-$(CONFIG_VME) := head.o +obj-$(CONFIG_HP300) := head.o +obj-$(CONFIG_Q40) := head.o +obj-$(CONFIG_SUN3X) := head.o +obj-$(CONFIG_VIRT) := head.o +obj-$(CONFIG_SUN3) := sun3-head.o + +obj-y += entry.o irq.o module.o process.o ptrace.o obj-y += setup.o signal.o sys_m68k.o syscalltable.o time.o traps.o obj-$(CONFIG_MMU_MOTOROLA) += ints.o vectors.o diff --git a/arch/microblaze/kernel/Makefile b/arch/microblaze/kernel/Makefile index 15a20eb814ce..4393bee64eaf 100644 --- a/arch/microblaze/kernel/Makefile +++ b/arch/microblaze/kernel/Makefile @@ -12,9 +12,9 @@ CFLAGS_REMOVE_ftrace.o = -pg CFLAGS_REMOVE_process.o = -pg endif -extra-y := head.o vmlinux.lds +extra-y := vmlinux.lds -obj-y += dma.o exceptions.o \ +obj-y += head.o dma.o exceptions.o \ hw_exception_handler.o irq.o \ process.o prom.o ptrace.o \ reset.o setup.o signal.o sys_microblaze.o timer.o traps.o unwind.o diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile index 7c96282bff2e..5d1addac5e28 100644 --- a/arch/mips/kernel/Makefile +++ b/arch/mips/kernel/Makefile @@ -3,9 +3,9 @@ # Makefile for the Linux/MIPS kernel. # -extra-y := head.o vmlinux.lds +extra-y := vmlinux.lds -obj-y += branch.o cmpxchg.o elf.o entry.o genex.o idle.o irq.o \ +obj-y += head.o branch.o cmpxchg.o elf.o entry.o genex.o idle.o irq.o \ process.o prom.o ptrace.o reset.o setup.o signal.o \ syscall.o time.o topology.o traps.o unaligned.o watch.o \ vdso.o cacheinfo.o diff --git a/arch/nios2/kernel/Makefile b/arch/nios2/kernel/Makefile index 0b645e1e3158..78a913181fa1 100644 --- a/arch/nios2/kernel/Makefile +++ b/arch/nios2/kernel/Makefile @@ -3,9 +3,9 @@ # Makefile for the nios2 linux kernel. # -extra-y += head.o extra-y += vmlinux.lds +obj-y += head.o obj-y += cpuinfo.o obj-y += entry.o obj-y += insnemu.o diff --git a/arch/openrisc/kernel/Makefile b/arch/openrisc/kernel/Makefile index 2d172e79f58d..79129161f3e0 100644 --- a/arch/openrisc/kernel/Makefile +++ b/arch/openrisc/kernel/Makefile @@ -3,9 +3,9 @@ # Makefile for the linux kernel. # -extra-y := head.o vmlinux.lds +extra-y := vmlinux.lds -obj-y := setup.o or32_ksyms.o process.o dma.o \ +obj-y := head.o setup.o or32_ksyms.o process.o dma.o \ traps.o time.o irq.o entry.o ptrace.o signal.o \ sys_call_table.o unwinder.o diff --git a/arch/parisc/kernel/Makefile b/arch/parisc/kernel/Makefile index d0bfac89a842..3d138c9cf9ce 100644 --- a/arch/parisc/kernel/Makefile +++ b/arch/parisc/kernel/Makefile @@ -3,9 +3,9 @@ # Makefile for arch/parisc/kernel # -extra-y := head.o vmlinux.lds +extra-y := vmlinux.lds -obj-y := cache.o pacache.o setup.o pdt.o traps.o time.o irq.o \ +obj-y := head.o cache.o pacache.o setup.o pdt.o traps.o time.o irq.o \ pa7300lc.o syscall.o entry.o sys_parisc.o firmware.o \ ptrace.o hardware.o inventory.o drivers.o alternative.o \ signal.o hpmc.o real2.o parisc_ksyms.o unaligned.o \ diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index 06d2d1f78f71..ad3decb9f20b 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -118,12 +118,12 @@ obj-$(CONFIG_PPC_FSL_BOOK3E) += cpu_setup_fsl_booke.o obj-$(CONFIG_PPC_DOORBELL) += dbell.o obj-$(CONFIG_JUMP_LABEL) += jump_label.o -extra-$(CONFIG_PPC64) := head_64.o -extra-$(CONFIG_PPC_BOOK3S_32) := head_book3s_32.o -extra-$(CONFIG_40x) := head_40x.o -extra-$(CONFIG_44x) := head_44x.o -extra-$(CONFIG_FSL_BOOKE) := head_fsl_booke.o -extra-$(CONFIG_PPC_8xx) := head_8xx.o +obj-$(CONFIG_PPC64) += head_64.o +obj-$(CONFIG_PPC_BOOK3S_32) += head_book3s_32.o +obj-$(CONFIG_40x) += head_40x.o +obj-$(CONFIG_44x) += head_44x.o +obj-$(CONFIG_FSL_BOOKE) += head_fsl_booke.o +obj-$(CONFIG_PPC_8xx) += head_8xx.o extra-y += vmlinux.lds obj-$(CONFIG_RELOCATABLE) += reloc_$(BITS).o @@ -198,10 +198,10 @@ KCOV_INSTRUMENT_paca.o := n CFLAGS_setup_64.o += -fno-stack-protector CFLAGS_paca.o += -fno-stack-protector -extra-$(CONFIG_PPC_FPU) += fpu.o -extra-$(CONFIG_ALTIVEC) += vector.o -extra-$(CONFIG_PPC64) += entry_64.o -extra-$(CONFIG_PPC_OF_BOOT_TRAMPOLINE) += prom_init.o +obj-$(CONFIG_PPC_FPU) += fpu.o +obj-$(CONFIG_ALTIVEC) += vector.o +obj-$(CONFIG_PPC64) += entry_64.o +obj-$(CONFIG_PPC_OF_BOOT_TRAMPOLINE) += prom_init.o extra-$(CONFIG_PPC_OF_BOOT_TRAMPOLINE) += prom_init_check diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile index 33bb60a354cd..db6e4b1294ba 100644 --- a/arch/riscv/kernel/Makefile +++ b/arch/riscv/kernel/Makefile @@ -28,9 +28,9 @@ KASAN_SANITIZE_cpufeature.o := n endif endif -extra-y += head.o extra-y += vmlinux.lds +obj-y += head.o obj-y += soc.o obj-$(CONFIG_RISCV_ALTERNATIVE) += alternative.o obj-y += cpu.o diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile index 3cbfa9fddd9a..7ce00816b8df 100644 --- a/arch/s390/kernel/Makefile +++ b/arch/s390/kernel/Makefile @@ -33,7 +33,7 @@ CFLAGS_stacktrace.o += -fno-optimize-sibling-calls CFLAGS_dumpstack.o += -fno-optimize-sibling-calls CFLAGS_unwind_bc.o += -fno-optimize-sibling-calls -obj-y := traps.o time.o process.o earlypgm.o early.o setup.o idle.o vtime.o +obj-y := head64.o traps.o time.o process.o earlypgm.o early.o setup.o idle.o vtime.o obj-y += processor.o syscall.o ptrace.o signal.o cpcmd.o ebcdic.o nmi.o obj-y += debug.o irq.o ipl.o dis.o diag.o vdso.o cpufeature.o obj-y += sysinfo.o lgr.o os_info.o machine_kexec.o @@ -42,7 +42,7 @@ obj-y += entry.o reipl.o relocate_kernel.o kdebugfs.o alternative.o obj-y += nospec-branch.o ipl_vmparm.o machine_kexec_reloc.o unwind_bc.o obj-y += smp.o text_amode31.o stacktrace.o -extra-y += head64.o vmlinux.lds +extra-y += vmlinux.lds obj-$(CONFIG_SYSFS) += nospec-sysfs.o CFLAGS_REMOVE_nospec-branch.o += $(CC_FLAGS_EXPOLINE) diff --git a/arch/sh/kernel/Makefile b/arch/sh/kernel/Makefile index aa0fbc9202b1..69cd9ac4b2ab 100644 --- a/arch/sh/kernel/Makefile +++ b/arch/sh/kernel/Makefile @@ -3,7 +3,7 @@ # Makefile for the Linux/SuperH kernel. # -extra-y := head_32.o vmlinux.lds +extra-y := vmlinux.lds ifdef CONFIG_FUNCTION_TRACER # Do not profile debug and lowlevel utilities @@ -12,7 +12,7 @@ endif CFLAGS_REMOVE_return_address.o = -pg -obj-y := debugtraps.o dumpstack.o \ +obj-y := head_32.o debugtraps.o dumpstack.o \ idle.o io.o irq.o irq_32.o kdebugfs.o \ machvec.o nmi_debug.o process.o \ process_32.o ptrace.o ptrace_32.o \ diff --git a/arch/sparc/kernel/Makefile b/arch/sparc/kernel/Makefile index d3a0e072ebe8..b328e4a0bd57 100644 --- a/arch/sparc/kernel/Makefile +++ b/arch/sparc/kernel/Makefile @@ -7,8 +7,6 @@ asflags-y := -ansi ccflags-y := -Werror -extra-y := head_$(BITS).o - # Undefine sparc when processing vmlinux.lds - it is used # And teach CPP we are doing $(BITS) builds (for this case) CPPFLAGS_vmlinux.lds := -Usparc -m$(BITS) @@ -22,6 +20,7 @@ CFLAGS_REMOVE_perf_event.o := -pg CFLAGS_REMOVE_pcr.o := -pg endif +obj-y := head_$(BITS).o obj-$(CONFIG_SPARC64) += urtt_fill.o obj-$(CONFIG_SPARC32) += entry.o wof.o wuf.o obj-$(CONFIG_SPARC32) += etrap_32.o diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index a20a5ebfacd7..956e50ca06e0 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -3,10 +3,6 @@ # Makefile for the linux kernel. # -extra-y := head_$(BITS).o -extra-y += head$(BITS).o -extra-y += ebda.o -extra-y += platform-quirks.o extra-y += vmlinux.lds CPPFLAGS_vmlinux.lds += -U$(UTS_MACHINE) @@ -42,7 +38,11 @@ KCOV_INSTRUMENT := n CFLAGS_irq.o := -I $(srctree)/$(src)/../include/asm/trace -obj-y := process_$(BITS).o signal.o +obj-y += head_$(BITS).o +obj-y += head$(BITS).o +obj-y += ebda.o +obj-y += platform-quirks.o +obj-y += process_$(BITS).o signal.o obj-$(CONFIG_COMPAT) += signal_compat.o obj-y += traps.o idt.o irq.o irq_$(BITS).o dumpstack_$(BITS).o obj-y += time.o ioport.o dumpstack.o nmi.o diff --git a/arch/xtensa/kernel/Makefile b/arch/xtensa/kernel/Makefile index 897c1c741058..f28b8e3d717e 100644 --- a/arch/xtensa/kernel/Makefile +++ b/arch/xtensa/kernel/Makefile @@ -3,9 +3,9 @@ # Makefile for the Linux/Xtensa kernel. # -extra-y := head.o vmlinux.lds +extra-y := vmlinux.lds -obj-y := align.o coprocessor.o entry.o irq.o platform.o process.o \ +obj-y := head.o align.o coprocessor.o entry.o irq.o platform.o process.o \ ptrace.o setup.o signal.o stacktrace.o syscall.o time.o traps.o \ vectors.o diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index 40a3e9b0512b..7740ce3b29e8 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -70,13 +70,12 @@ quiet_cmd_vmlinux_objs = GEN $@ for f in $(real-prereqs); do \ case $${f} in \ *libgcc.a) ;; \ - *.a) $(AR) t $${f} ;; \ - *) echo $${f} ;; \ + *) $(AR) t $${f} ;; \ esac \ done > $@ targets += .vmlinux.objs -.vmlinux.objs: $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS) FORCE +.vmlinux.objs: vmlinux.a $(KBUILD_VMLINUX_LIBS) FORCE $(call if_changed,vmlinux_objs) vmlinux.o-if-present := $(wildcard vmlinux.o) diff --git a/scripts/Makefile.vmlinux_o b/scripts/Makefile.vmlinux_o index 7d531b825712..68c22879bade 100644 --- a/scripts/Makefile.vmlinux_o +++ b/scripts/Makefile.vmlinux_o @@ -18,7 +18,7 @@ quiet_cmd_gen_initcalls_lds = GEN $@ $(PERL) $(real-prereqs) > $@ .tmp_initcalls.lds: $(srctree)/scripts/generate_initcall_order.pl \ - $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS) FORCE + vmlinux.a $(KBUILD_VMLINUX_LIBS) FORCE $(call if_changed,gen_initcalls_lds) targets := .tmp_initcalls.lds @@ -48,7 +48,7 @@ quiet_cmd_ld_vmlinux.o = LD $@ cmd_ld_vmlinux.o = \ $(LD) ${KBUILD_LDFLAGS} -r -o $@ \ $(addprefix -T , $(initcalls-lds)) \ - --whole-archive $(KBUILD_VMLINUX_OBJS) --no-whole-archive \ + --whole-archive vmlinux.a --no-whole-archive \ --start-group $(KBUILD_VMLINUX_LIBS) --end-group \ $(cmd_objtool) @@ -57,7 +57,7 @@ define rule_ld_vmlinux.o $(call cmd,gen_objtooldep) endef -vmlinux.o: $(initcalls-lds) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS) FORCE +vmlinux.o: $(initcalls-lds) vmlinux.a $(KBUILD_VMLINUX_LIBS) FORCE $(call if_changed_rule,ld_vmlinux.o) targets += vmlinux.o diff --git a/scripts/clang-tools/gen_compile_commands.py b/scripts/clang-tools/gen_compile_commands.py index 47da25b3ba7d..d800b2c0af97 100755 --- a/scripts/clang-tools/gen_compile_commands.py +++ b/scripts/clang-tools/gen_compile_commands.py @@ -109,20 +109,6 @@ def to_cmdfile(path): return os.path.join(dir, '.' + base + '.cmd') -def cmdfiles_for_o(obj): - """Generate the iterator of .cmd files associated with the object - - Yield the .cmd file used to build the given object - - Args: - obj: The object path - - Yields: - The path to .cmd file - """ - yield to_cmdfile(obj) - - def cmdfiles_for_a(archive, ar): """Generate the iterator of .cmd files associated with the archive. @@ -211,13 +197,10 @@ def main(): for path in paths: # If 'path' is a directory, handle all .cmd files under it. # Otherwise, handle .cmd files associated with the file. - # Most of built-in objects are linked via archives (built-in.a or lib.a) - # but some objects are linked to vmlinux directly. + # built-in objects are linked via vmlinux.a # Modules are listed in modules.order. if os.path.isdir(path): cmdfiles = cmdfiles_in_dir(path) - elif path.endswith('.o'): - cmdfiles = cmdfiles_for_o(path) elif path.endswith('.a'): cmdfiles = cmdfiles_for_a(path, ar) elif path.endswith('modules.order'): diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 6a197d8a88ac..23ac13fd9d89 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -3,17 +3,15 @@ # # link vmlinux # -# vmlinux is linked from the objects selected by $(KBUILD_VMLINUX_OBJS) and -# $(KBUILD_VMLINUX_LIBS). Most are built-in.a files from top-level directories -# in the kernel tree, others are specified in arch/$(ARCH)/Makefile. +# vmlinux is linked from the objects in vmlinux.a and $(KBUILD_VMLINUX_LIBS). +# vmlinux.a contains objects that are linked unconditionally. # $(KBUILD_VMLINUX_LIBS) are archives which are linked conditionally # (not within --whole-archive), and do not require symbol indexes added. # # vmlinux # ^ # | -# +--< $(KBUILD_VMLINUX_OBJS) -# | +--< init/built-in.a drivers/built-in.a mm/built-in.a + more +# +--< vmlinux.a # | # +--< $(KBUILD_VMLINUX_LIBS) # | +--< lib/lib.a + more @@ -67,7 +65,7 @@ vmlinux_link() objs=vmlinux.o libs= else - objs="${KBUILD_VMLINUX_OBJS}" + objs=vmlinux.a libs="${KBUILD_VMLINUX_LIBS}" fi -- cgit v1.2.3-59-g8ed1b From ce697ccee1a8661da4e23fbe5f3d45d8d6922c20 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 25 Sep 2022 03:19:15 +0900 Subject: kbuild: remove head-y syntax Kbuild puts the objects listed in head-y at the head of vmlinux. Conventionally, we do this for head*.S, which contains the kernel entry point. A counter approach is to control the section order by the linker script. Actually, the code marked as __HEAD goes into the ".head.text" section, which is placed before the normal ".text" section. I do not know if both of them are needed. From the build system perspective, head-y is not mandatory. If you can achieve the proper code placement by the linker script only, it would be cleaner. I collected the current head-y objects into head-object-list.txt. It is a whitelist. My hope is it will be reduced in the long run. Signed-off-by: Masahiro Yamada Tested-by: Nick Desaulniers Reviewed-by: Nicolas Schier --- Documentation/kbuild/makefiles.rst | 9 ++++--- Makefile | 4 +-- arch/alpha/Makefile | 2 -- arch/arc/Makefile | 2 -- arch/arm/Makefile | 3 --- arch/arm64/Makefile | 3 --- arch/csky/Makefile | 2 -- arch/hexagon/Makefile | 2 -- arch/ia64/Makefile | 1 - arch/loongarch/Makefile | 2 -- arch/m68k/Makefile | 9 ------- arch/microblaze/Makefile | 1 - arch/mips/Makefile | 2 -- arch/nios2/Makefile | 1 - arch/openrisc/Makefile | 2 -- arch/parisc/Makefile | 2 -- arch/powerpc/Makefile | 12 --------- arch/riscv/Makefile | 2 -- arch/s390/Makefile | 2 -- arch/sh/Makefile | 2 -- arch/sparc/Makefile | 2 -- arch/x86/Makefile | 5 ---- arch/xtensa/Makefile | 2 -- scripts/head-object-list.txt | 53 ++++++++++++++++++++++++++++++++++++++ 24 files changed, 60 insertions(+), 67 deletions(-) create mode 100644 scripts/head-object-list.txt (limited to 'scripts') diff --git a/Documentation/kbuild/makefiles.rst b/Documentation/kbuild/makefiles.rst index 5a6a8426cc97..60134ddf3db1 100644 --- a/Documentation/kbuild/makefiles.rst +++ b/Documentation/kbuild/makefiles.rst @@ -1070,8 +1070,7 @@ When kbuild executes, the following steps are followed (roughly): - The values of the above variables are expanded in arch/$(SRCARCH)/Makefile. 5) All object files are then linked and the resulting file vmlinux is located at the root of the obj tree. - The very first objects linked are listed in head-y, assigned by - arch/$(SRCARCH)/Makefile. + The very first objects linked are listed in scripts/head-object-list.txt. 6) Finally, the architecture-specific part does any required post processing and builds the final bootimage. - This includes building boot records @@ -1219,6 +1218,9 @@ When kbuild executes, the following steps are followed (roughly): All object files for vmlinux. They are linked to vmlinux in the same order as listed in KBUILD_VMLINUX_OBJS. + The objects listed in scripts/head-object-list.txt are exceptions; + they are placed before the other objects. + KBUILD_VMLINUX_LIBS All .a "lib" files for vmlinux. KBUILD_VMLINUX_OBJS and @@ -1262,8 +1264,7 @@ When kbuild executes, the following steps are followed (roughly): machinery is all architecture-independent. - head-y, core-y, libs-y, drivers-y - $(head-y) lists objects to be linked first in vmlinux. + core-y, libs-y, drivers-y $(libs-y) lists directories where a lib.a archive can be located. diff --git a/Makefile b/Makefile index 8da45f76ec31..e4186c171049 100644 --- a/Makefile +++ b/Makefile @@ -1147,10 +1147,10 @@ quiet_cmd_ar_vmlinux.a = AR $@ cmd_ar_vmlinux.a = \ rm -f $@; \ $(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \ - $(AR) mPiT $$($(AR) t $@ | head -n1) $@ $(head-y) + $(AR) mPiT $$($(AR) t $@ | head -n1) $@ $$($(AR) t $@ | grep -F --file=$(srctree)/scripts/head-object-list.txt) targets += vmlinux.a -vmlinux.a: $(KBUILD_VMLINUX_OBJS) autoksyms_recursive FORCE +vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt autoksyms_recursive FORCE $(call if_changed,ar_vmlinux.a) vmlinux.o: vmlinux.a $(KBUILD_VMLINUX_LIBS) FORCE diff --git a/arch/alpha/Makefile b/arch/alpha/Makefile index 881cb913e23a..45158024085e 100644 --- a/arch/alpha/Makefile +++ b/arch/alpha/Makefile @@ -36,8 +36,6 @@ cflags-y += $(cpuflags-y) # BWX is most important, but we don't really want any emulation ever. KBUILD_CFLAGS += $(cflags-y) -Wa,-mev6 -head-y := arch/alpha/kernel/head.o - libs-y += arch/alpha/lib/ # export what is needed by arch/alpha/boot/Makefile diff --git a/arch/arc/Makefile b/arch/arc/Makefile index efc54f3e35e0..329400a1c355 100644 --- a/arch/arc/Makefile +++ b/arch/arc/Makefile @@ -82,8 +82,6 @@ KBUILD_CFLAGS += $(cflags-y) KBUILD_AFLAGS += $(KBUILD_CFLAGS) KBUILD_LDFLAGS += $(ldflags-y) -head-y := arch/arc/kernel/head.o - # w/o this dtb won't embed into kernel binary core-y += arch/arc/boot/dts/ diff --git a/arch/arm/Makefile b/arch/arm/Makefile index 56f655deebb1..29d15c9a433e 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -134,9 +134,6 @@ KBUILD_AFLAGS +=$(CFLAGS_ABI) $(AFLAGS_ISA) $(arch-y) $(tune-y) -include asm/uni CHECKFLAGS += -D__arm__ -#Default value -head-y := arch/arm/kernel/head$(MMUEXT).o - # Text offset. This list is sorted numerically by address in order to # provide a means to avoid/resolve conflicts in multi-arch kernels. # Note: the 32kB below this value is reserved for use by the kernel diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile index 6d9d4a58b898..6e03f15bb041 100644 --- a/arch/arm64/Makefile +++ b/arch/arm64/Makefile @@ -133,9 +133,6 @@ ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_REGS),y) CC_FLAGS_FTRACE := -fpatchable-function-entry=2 endif -# Default value -head-y := arch/arm64/kernel/head.o - ifeq ($(CONFIG_KASAN_SW_TAGS), y) KASAN_SHADOW_SCALE_SHIFT := 4 else ifeq ($(CONFIG_KASAN_GENERIC), y) diff --git a/arch/csky/Makefile b/arch/csky/Makefile index 4e1d619fd5c6..0e4237e55758 100644 --- a/arch/csky/Makefile +++ b/arch/csky/Makefile @@ -59,8 +59,6 @@ LDFLAGS += -EL KBUILD_AFLAGS += $(KBUILD_CFLAGS) -head-y := arch/csky/kernel/head.o - core-y += arch/csky/$(CSKYABI)/ libs-y += arch/csky/lib/ \ diff --git a/arch/hexagon/Makefile b/arch/hexagon/Makefile index 44312bc147d8..92d005958dfb 100644 --- a/arch/hexagon/Makefile +++ b/arch/hexagon/Makefile @@ -32,5 +32,3 @@ KBUILD_LDFLAGS += $(ldflags-y) TIR_NAME := r19 KBUILD_CFLAGS += -ffixed-$(TIR_NAME) -DTHREADINFO_REG=$(TIR_NAME) -D__linux__ KBUILD_AFLAGS += -DTHREADINFO_REG=$(TIR_NAME) - -head-y := arch/hexagon/kernel/head.o diff --git a/arch/ia64/Makefile b/arch/ia64/Makefile index e55c2f138656..56c4bb276b6e 100644 --- a/arch/ia64/Makefile +++ b/arch/ia64/Makefile @@ -44,7 +44,6 @@ quiet_cmd_objcopy = OBJCOPY $@ cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@ KBUILD_CFLAGS += $(cflags-y) -head-y := arch/ia64/kernel/head.o libs-y += arch/ia64/lib/ diff --git a/arch/loongarch/Makefile b/arch/loongarch/Makefile index ec3de6191276..131fc210c2bf 100644 --- a/arch/loongarch/Makefile +++ b/arch/loongarch/Makefile @@ -72,8 +72,6 @@ CHECKFLAGS += $(shell $(CC) $(KBUILD_CFLAGS) -dM -E -x c /dev/null | \ sed -e "s/^\#define /-D'/" -e "s/ /'='/" -e "s/$$/'/" -e 's/\$$/&&/g') endif -head-y := arch/loongarch/kernel/head.o - libs-y += arch/loongarch/lib/ ifeq ($(KBUILD_EXTMOD),) diff --git a/arch/m68k/Makefile b/arch/m68k/Makefile index e358605b70ba..43e39040d3ac 100644 --- a/arch/m68k/Makefile +++ b/arch/m68k/Makefile @@ -86,15 +86,6 @@ ifdef CONFIG_KGDB KBUILD_CFLAGS := $(subst -fomit-frame-pointer,,$(KBUILD_CFLAGS)) -g endif -# -# Select the assembler head startup code. Order is important. The default -# head code is first, processor specific selections can override it after. -# -head-y := arch/m68k/kernel/head.o -head-$(CONFIG_SUN3) := arch/m68k/kernel/sun3-head.o -head-$(CONFIG_M68000) := arch/m68k/68000/head.o -head-$(CONFIG_COLDFIRE) := arch/m68k/coldfire/head.o - libs-y += arch/m68k/lib/ diff --git a/arch/microblaze/Makefile b/arch/microblaze/Makefile index 1826d9ce4459..3f8a86c4336a 100644 --- a/arch/microblaze/Makefile +++ b/arch/microblaze/Makefile @@ -48,7 +48,6 @@ CPUFLAGS-1 += $(call cc-option,-mcpu=v$(CPU_VER)) # r31 holds current when in kernel mode KBUILD_CFLAGS += -ffixed-r31 $(CPUFLAGS-y) $(CPUFLAGS-1) $(CPUFLAGS-2) -head-y := arch/microblaze/kernel/head.o libs-y += arch/microblaze/lib/ boot := arch/microblaze/boot diff --git a/arch/mips/Makefile b/arch/mips/Makefile index 4d2a3e73fc45..b296e33f8e33 100644 --- a/arch/mips/Makefile +++ b/arch/mips/Makefile @@ -324,8 +324,6 @@ endif OBJCOPYFLAGS += --remove-section=.reginfo -head-y := arch/mips/kernel/head.o - libs-y += arch/mips/lib/ libs-$(CONFIG_MIPS_FP_SUPPORT) += arch/mips/math-emu/ diff --git a/arch/nios2/Makefile b/arch/nios2/Makefile index 3f34e6831863..f1ff4ce0f1a2 100644 --- a/arch/nios2/Makefile +++ b/arch/nios2/Makefile @@ -37,7 +37,6 @@ KBUILD_CFLAGS += -DUTS_SYSNAME=\"$(UTS_SYSNAME)\" KBUILD_CFLAGS += -fno-builtin KBUILD_CFLAGS += -G 0 -head-y := arch/nios2/kernel/head.o libs-y += arch/nios2/lib/ $(LIBGCC) INSTALL_PATH ?= /tftpboot diff --git a/arch/openrisc/Makefile b/arch/openrisc/Makefile index b446510173cd..68249521db5a 100644 --- a/arch/openrisc/Makefile +++ b/arch/openrisc/Makefile @@ -55,8 +55,6 @@ ifeq ($(CONFIG_OPENRISC_HAVE_INST_SEXT),y) KBUILD_CFLAGS += $(call cc-option,-msext) endif -head-y := arch/openrisc/kernel/head.o - libs-y += $(LIBGCC) PHONY += vmlinux.bin diff --git a/arch/parisc/Makefile b/arch/parisc/Makefile index e38d993d87f2..a2d8600521f9 100644 --- a/arch/parisc/Makefile +++ b/arch/parisc/Makefile @@ -113,8 +113,6 @@ cflags-$(CONFIG_PA7100LC) += -march=1.1 -mschedule=7100LC cflags-$(CONFIG_PA7300LC) += -march=1.1 -mschedule=7300 cflags-$(CONFIG_PA8X00) += -march=2.0 -mschedule=8000 -head-y := arch/parisc/kernel/head.o - KBUILD_CFLAGS += $(cflags-y) LIBGCC := $(shell $(CC) -print-libgcc-file-name) export LIBGCC diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile index 02742facf895..89c27827a11f 100644 --- a/arch/powerpc/Makefile +++ b/arch/powerpc/Makefile @@ -226,18 +226,6 @@ KBUILD_CFLAGS += $(cpu-as-y) KBUILD_AFLAGS += $(aflags-y) KBUILD_CFLAGS += $(cflags-y) -head-$(CONFIG_PPC64) := arch/powerpc/kernel/head_64.o -head-$(CONFIG_PPC_BOOK3S_32) := arch/powerpc/kernel/head_book3s_32.o -head-$(CONFIG_PPC_8xx) := arch/powerpc/kernel/head_8xx.o -head-$(CONFIG_40x) := arch/powerpc/kernel/head_40x.o -head-$(CONFIG_44x) := arch/powerpc/kernel/head_44x.o -head-$(CONFIG_FSL_BOOKE) := arch/powerpc/kernel/head_fsl_booke.o - -head-$(CONFIG_PPC64) += arch/powerpc/kernel/entry_64.o -head-$(CONFIG_PPC_FPU) += arch/powerpc/kernel/fpu.o -head-$(CONFIG_ALTIVEC) += arch/powerpc/kernel/vector.o -head-$(CONFIG_PPC_OF_BOOT_TRAMPOLINE) += arch/powerpc/kernel/prom_init.o - # Default to zImage, override when needed all: zImage diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index 3fa8ef336822..e013df8e7b8b 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -110,8 +110,6 @@ else KBUILD_IMAGE := $(boot)/Image.gz endif -head-y := arch/riscv/kernel/head.o - libs-y += arch/riscv/lib/ libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a diff --git a/arch/s390/Makefile b/arch/s390/Makefile index 4cb5d17e7ead..de6d8b2ea4d8 100644 --- a/arch/s390/Makefile +++ b/arch/s390/Makefile @@ -119,8 +119,6 @@ export KBUILD_CFLAGS_DECOMPRESSOR OBJCOPYFLAGS := -O binary -head-y := arch/s390/kernel/head64.o - libs-y += arch/s390/lib/ drivers-y += drivers/s390/ diff --git a/arch/sh/Makefile b/arch/sh/Makefile index b39412bf91fb..5c8776482530 100644 --- a/arch/sh/Makefile +++ b/arch/sh/Makefile @@ -114,8 +114,6 @@ endif export ld-bfd -head-y := arch/sh/kernel/head_32.o - # Mach groups machdir-$(CONFIG_SOLUTION_ENGINE) += mach-se machdir-$(CONFIG_SH_HP6XX) += mach-hp6xx diff --git a/arch/sparc/Makefile b/arch/sparc/Makefile index fe58a410b4ce..a4ea5b05f288 100644 --- a/arch/sparc/Makefile +++ b/arch/sparc/Makefile @@ -56,8 +56,6 @@ endif endif -head-y := arch/sparc/kernel/head_$(BITS).o - libs-y += arch/sparc/prom/ libs-y += arch/sparc/lib/ diff --git a/arch/x86/Makefile b/arch/x86/Makefile index bafbd905e6e7..9afd323c6916 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -234,11 +234,6 @@ archheaders: ### # Kernel objects -head-y := arch/x86/kernel/head_$(BITS).o -head-y += arch/x86/kernel/head$(BITS).o -head-y += arch/x86/kernel/ebda.o -head-y += arch/x86/kernel/platform-quirks.o - libs-y += arch/x86/lib/ # drivers-y are linked after core-y diff --git a/arch/xtensa/Makefile b/arch/xtensa/Makefile index 5097caa7bf0c..bfd8e433ed62 100644 --- a/arch/xtensa/Makefile +++ b/arch/xtensa/Makefile @@ -55,8 +55,6 @@ KBUILD_CPPFLAGS += $(patsubst %,-I$(srctree)/%include,$(vardirs) $(plfdirs)) KBUILD_DEFCONFIG := iss_defconfig -head-y := arch/xtensa/kernel/head.o - libs-y += arch/xtensa/lib/ boot := arch/xtensa/boot diff --git a/scripts/head-object-list.txt b/scripts/head-object-list.txt new file mode 100644 index 000000000000..dd2ba2eda636 --- /dev/null +++ b/scripts/head-object-list.txt @@ -0,0 +1,53 @@ +# Head objects +# +# The objects listed here are placed at the head of vmlinux. A typical use-case +# is an object that contains the entry point. This is kept for compatibility +# with head-y, which Kbuild used to support. +# +# A counter approach is to control the section placement by the linker script. +# The code marked as __HEAD goes into the ".head.text" section, which is placed +# before the normal ".text" section. +# +# If you can achieve the correct code ordering by linker script, please delete +# the entry from this file. +# +arch/alpha/kernel/head.o +arch/arc/kernel/head.o +arch/arm/kernel/head-nommu.o +arch/arm/kernel/head.o +arch/arm64/kernel/head.o +arch/csky/kernel/head.o +arch/hexagon/kernel/head.o +arch/ia64/kernel/head.o +arch/loongarch/kernel/head.o +arch/m68k/68000/head.o +arch/m68k/coldfire/head.o +arch/m68k/kernel/head.o +arch/m68k/kernel/sun3-head.o +arch/microblaze/kernel/head.o +arch/mips/kernel/head.o +arch/nios2/kernel/head.o +arch/openrisc/kernel/head.o +arch/parisc/kernel/head.o +arch/powerpc/kernel/head_40x.o +arch/powerpc/kernel/head_44x.o +arch/powerpc/kernel/head_64.o +arch/powerpc/kernel/head_8xx.o +arch/powerpc/kernel/head_book3s_32.o +arch/powerpc/kernel/head_fsl_booke.o +arch/powerpc/kernel/entry_64.o +arch/powerpc/kernel/fpu.o +arch/powerpc/kernel/vector.o +arch/powerpc/kernel/prom_init.o +arch/riscv/kernel/head.o +arch/s390/kernel/head64.o +arch/sh/kernel/head_32.o +arch/sparc/kernel/head_32.o +arch/sparc/kernel/head_64.o +arch/x86/kernel/head_32.o +arch/x86/kernel/head_64.o +arch/x86/kernel/head32.o +arch/x86/kernel/head64.o +arch/x86/kernel/ebda.o +arch/x86/kernel/platform-quirks.o +arch/xtensa/kernel/head.o -- cgit v1.2.3-59-g8ed1b From c13461693ea21d787f82232ce3a5667da370d973 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 26 Sep 2022 18:02:25 +0900 Subject: mksysmap: update comment about __crc_* Since commit 7b4537199a4a ("kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS"), __crc_* symbols never become absolute. Keep ignoring __crc_*, but update the comment. Signed-off-by: Masahiro Yamada --- scripts/mksysmap | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'scripts') diff --git a/scripts/mksysmap b/scripts/mksysmap index ad8bbc52267d..bc5396e255d8 100755 --- a/scripts/mksysmap +++ b/scripts/mksysmap @@ -37,8 +37,8 @@ # readprofile starts reading symbols when _stext is found, and # continue until it finds a symbol which is not either of 'T', 't', -# 'W' or 'w'. __crc_ are 'A' and placed in the middle -# so we just ignore them to let readprofile continue to work. -# (At least sparc64 has __crc_ in the middle). - +# 'W' or 'w'. +# +# Ignored prefixes: +# __crc_ - modversions $NM -n $1 | grep -v '\( [aNUw] \)\|\(__crc_\)\|\( \$[adt]\)\|\( \.L\)\|\( L0\)' > $2 -- cgit v1.2.3-59-g8ed1b From 94ff2f63d6a31501ceb36ebc600240937cfff35f Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 26 Sep 2022 18:02:26 +0900 Subject: kbuild: reuse mksysmap output for kallsyms scripts/mksysmap internally runs ${NM} (dropping some symbols). When CONFIG_KALLSYMS=y, mksysmap creates .tmp_System.map, but it is almost the same as the output from the ${NM} invocation in kallsyms(). It is true scripts/mksysmap drops some symbols, but scripts/kallsyms.c ignores more anyway. Keep the mksysmap output as *.syms, and reuse it for kallsyms and 'cmp -s'. It saves one ${NM} invocation. Signed-off-by: Masahiro Yamada --- scripts/link-vmlinux.sh | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) (limited to 'scripts') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 23ac13fd9d89..6492c0862657 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -157,7 +157,7 @@ kallsyms() fi info KSYMS ${2} - ${NM} -n ${1} | scripts/kallsyms ${kallsymopt} > ${2} + cat ${1} | scripts/kallsyms ${kallsymopt} > ${2} } # Perform one step in kallsyms generation, including temporary linking of @@ -170,7 +170,8 @@ kallsyms_step() kallsyms_S=${kallsyms_vmlinux}.S vmlinux_link ${kallsyms_vmlinux} "${kallsymso_prev}" ${btf_vmlinux_bin_o} - kallsyms ${kallsyms_vmlinux} ${kallsyms_S} + mksysmap ${kallsyms_vmlinux} ${kallsyms_vmlinux}.syms + kallsyms ${kallsyms_vmlinux}.syms ${kallsyms_S} info AS ${kallsyms_S} ${CC} ${NOSTDINC_FLAGS} ${LINUXINCLUDE} ${KBUILD_CPPFLAGS} \ @@ -182,6 +183,7 @@ kallsyms_step() # See mksymap for additional details mksysmap() { + info NM ${2} ${CONFIG_SHELL} "${srctree}/scripts/mksysmap" ${1} ${2} } @@ -283,7 +285,6 @@ if is_enabled CONFIG_DEBUG_INFO_BTF && is_enabled CONFIG_BPF; then ${RESOLVE_BTFIDS} vmlinux fi -info SYSMAP System.map mksysmap vmlinux System.map if is_enabled CONFIG_BUILDTIME_TABLE_SORT; then @@ -296,9 +297,7 @@ fi # step a (see comment above) if is_enabled CONFIG_KALLSYMS; then - mksysmap ${kallsyms_vmlinux} .tmp_System.map - - if ! cmp -s System.map .tmp_System.map; then + if ! cmp -s System.map ${kallsyms_vmlinux}.syms; then echo >&2 Inconsistent kallsyms data echo >&2 Try "make KALLSYMS_EXTRA_PASS=1" as a workaround exit 1 -- cgit v1.2.3-59-g8ed1b From a2833d1b07ab107db71a18e6f3855f6908886361 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 26 Sep 2022 18:02:27 +0900 Subject: kallsyms: drop duplicated ignore patterns from kallsyms.c Now that kallsyms.c parses the output from mksysmap, some symbols have already been dropped. Move comments to scripts/mksysmap. Also, make the grep command readable. Signed-off-by: Masahiro Yamada --- scripts/kallsyms.c | 3 --- scripts/mksysmap | 14 +++++++++++++- 2 files changed, 13 insertions(+), 4 deletions(-) (limited to 'scripts') diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c index f18e6dfc68c5..313cc8161123 100644 --- a/scripts/kallsyms.c +++ b/scripts/kallsyms.c @@ -107,9 +107,6 @@ static bool is_ignored_symbol(const char *name, char type) /* Symbol names that begin with the following are ignored.*/ static const char * const ignored_prefixes[] = { - "$", /* local symbols for ARM, MIPS, etc. */ - ".L", /* local labels, .LBB,.Ltmpxxx,.L__unnamed_xx,.LASANPC, etc. */ - "__crc_", /* modversions */ "__efistub_", /* arm64 EFI stub namespace */ "__kvm_nvhe_$", /* arm64 local symbols in non-VHE KVM namespace */ "__kvm_nvhe_.L", /* arm64 local symbols in non-VHE KVM namespace */ diff --git a/scripts/mksysmap b/scripts/mksysmap index bc5396e255d8..75f3dfd1c156 100755 --- a/scripts/mksysmap +++ b/scripts/mksysmap @@ -40,5 +40,17 @@ # 'W' or 'w'. # # Ignored prefixes: +# $ - local symbols for ARM, MIPS, etc. +# .L - local labels, .LBB,.Ltmpxxx,.L__unnamed_xx,.LASANPC, etc. # __crc_ - modversions -$NM -n $1 | grep -v '\( [aNUw] \)\|\(__crc_\)\|\( \$[adt]\)\|\( \.L\)\|\( L0\)' > $2 +# +# Ignored symbols: +# L0 - for LoongArch? + +$NM -n $1 | grep -v \ + -e ' [aNUw] ' \ + -e ' \$' \ + -e ' \.L' \ + -e ' __crc_' \ + -e ' L0$' \ +> $2 -- cgit v1.2.3-59-g8ed1b From aa221f2ea58655f5360e7b0c6fe5482f7c41855e Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 26 Sep 2022 18:02:28 +0900 Subject: kallsyms: take the input file instead of reading stdin This gets rid of the pipe operator connected with 'cat'. Also use getopt_long() to parse the command line. Signed-off-by: Masahiro Yamada --- scripts/kallsyms.c | 51 ++++++++++++++++++++++++++++++++----------------- scripts/link-vmlinux.sh | 2 +- 2 files changed, 34 insertions(+), 19 deletions(-) (limited to 'scripts') diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c index 313cc8161123..5b091625d4c5 100644 --- a/scripts/kallsyms.c +++ b/scripts/kallsyms.c @@ -18,6 +18,7 @@ * */ +#include #include #include #include @@ -71,7 +72,7 @@ static unsigned char best_table_len[256]; static void usage(void) { fprintf(stderr, "Usage: kallsyms [--all-symbols] [--absolute-percpu] " - "[--base-relative] < in.map > out.S\n"); + "[--base-relative] in.map > out.S\n"); exit(1); } @@ -310,12 +311,19 @@ static void shrink_table(void) } } -static void read_map(FILE *in) +static void read_map(const char *in) { + FILE *fp; struct sym_entry *sym; - while (!feof(in)) { - sym = read_symbol(in); + fp = fopen(in, "r"); + if (!fp) { + perror(in); + exit(1); + } + + while (!feof(fp)) { + sym = read_symbol(fp); if (!sym) continue; @@ -326,12 +334,15 @@ static void read_map(FILE *in) table = realloc(table, sizeof(*table) * table_size); if (!table) { fprintf(stderr, "out of memory\n"); + fclose(fp); exit (1); } } table[table_cnt++] = sym; } + + fclose(fp); } static void output_label(const char *label) @@ -762,22 +773,26 @@ static void record_relative_base(void) int main(int argc, char **argv) { - if (argc >= 2) { - int i; - for (i = 1; i < argc; i++) { - if(strcmp(argv[i], "--all-symbols") == 0) - all_symbols = 1; - else if (strcmp(argv[i], "--absolute-percpu") == 0) - absolute_percpu = 1; - else if (strcmp(argv[i], "--base-relative") == 0) - base_relative = 1; - else - usage(); - } - } else if (argc != 1) + while (1) { + static struct option long_options[] = { + {"all-symbols", no_argument, &all_symbols, 1}, + {"absolute-percpu", no_argument, &absolute_percpu, 1}, + {"base-relative", no_argument, &base_relative, 1}, + {}, + }; + + int c = getopt_long(argc, argv, "", long_options, NULL); + + if (c == -1) + break; + if (c != 0) + usage(); + } + + if (optind >= argc) usage(); - read_map(stdin); + read_map(argv[optind]); shrink_table(); if (absolute_percpu) make_percpus_absolute(); diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 6492c0862657..2782c5d1518b 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -157,7 +157,7 @@ kallsyms() fi info KSYMS ${2} - cat ${1} | scripts/kallsyms ${kallsymopt} > ${2} + scripts/kallsyms ${kallsymopt} ${1} > ${2} } # Perform one step in kallsyms generation, including temporary linking of -- cgit v1.2.3-59-g8ed1b From d32b55f4bb43466bc6cdd98a00f8a600bbf7e8ec Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 26 Sep 2022 18:02:29 +0900 Subject: kallsyms: ignore __kstrtab_* and __kstrtabns_* symbols Every EXPORT_SYMBOL creates __kstrtab_* and __kstrtabns_*, which consumes 15-20% of the kallsyms entries. For example, on the system built from the x86_64 defconfig, $ cat /proc/kallsyms | wc 129527 388581 5685465 $ cat /proc/kallsyms | grep __kstrtab | wc 23489 70467 1187932 We already ignore __crc_* symbols populated by EXPORT_SYMBOL, so it should be fine to ignore __kstrtab_* and __kstrtabns_* as well. This makes vmlinux a bit smaller. $ size vmlinux.before vmlinux.after text data bss dec hex filename 22785374 8559694 1413328 32758396 1f3da7c vmlinux.before 22785374 8137806 1413328 32336508 1ed6a7c vmlinux.after Signed-off-by: Masahiro Yamada --- scripts/mksysmap | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'scripts') diff --git a/scripts/mksysmap b/scripts/mksysmap index 75f3dfd1c156..16a08b8ef2f8 100755 --- a/scripts/mksysmap +++ b/scripts/mksysmap @@ -43,6 +43,8 @@ # $ - local symbols for ARM, MIPS, etc. # .L - local labels, .LBB,.Ltmpxxx,.L__unnamed_xx,.LASANPC, etc. # __crc_ - modversions +# __kstrtab_ - EXPORT_SYMBOL (symbol name) +# __kstrtabns_ - EXPORT_SYMBOL (namespace) # # Ignored symbols: # L0 - for LoongArch? @@ -52,5 +54,7 @@ $NM -n $1 | grep -v \ -e ' \$' \ -e ' \.L' \ -e ' __crc_' \ + -e ' __kstrtab_' \ + -e ' __kstrtabns_' \ -e ' L0$' \ > $2 -- cgit v1.2.3-59-g8ed1b From 7a342e6c7735e13b294374cb0a0f6283d8667496 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 28 Sep 2022 15:39:40 +0900 Subject: kbuild: move modules.builtin(.modinfo) rules to Makefile.vmlinux_o Do not build modules.builtin(.modinfo) as a side-effect of vmlinux. There are no good reason to rebuild them just because any of vmlinux's prerequistes (vmlinux.lds, .vmlinux.export.c, etc.) has been updated. Signed-off-by: Masahiro Yamada --- Makefile | 6 +++++- scripts/Makefile.vmlinux_o | 26 +++++++++++++++++++++++++- scripts/link-vmlinux.sh | 7 ------- 3 files changed, 30 insertions(+), 9 deletions(-) (limited to 'scripts') diff --git a/Makefile b/Makefile index e4186c171049..2fcbd753cb27 100644 --- a/Makefile +++ b/Makefile @@ -1153,9 +1153,13 @@ targets += vmlinux.a vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt autoksyms_recursive FORCE $(call if_changed,ar_vmlinux.a) -vmlinux.o: vmlinux.a $(KBUILD_VMLINUX_LIBS) FORCE +PHONY += vmlinux_o +vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS) $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o +vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o + @: + ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink) # Final link of vmlinux with optional arch pass after final link diff --git a/scripts/Makefile.vmlinux_o b/scripts/Makefile.vmlinux_o index 68c22879bade..0edfdb40364b 100644 --- a/scripts/Makefile.vmlinux_o +++ b/scripts/Makefile.vmlinux_o @@ -1,7 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only PHONY := __default -__default: vmlinux.o +__default: vmlinux.o modules.builtin.modinfo modules.builtin include include/config/auto.conf include $(srctree)/scripts/Kbuild.include @@ -62,6 +62,30 @@ vmlinux.o: $(initcalls-lds) vmlinux.a $(KBUILD_VMLINUX_LIBS) FORCE targets += vmlinux.o +# module.builtin.modinfo +# --------------------------------------------------------------------------- + +OBJCOPYFLAGS_modules.builtin.modinfo := -j .modinfo -O binary + +targets += modules.builtin.modinfo +modules.builtin.modinfo: vmlinux.o FORCE + $(call if_changed,objcopy) + +# module.builtin +# --------------------------------------------------------------------------- + +# The second line aids cases where multiple modules share the same object. + +quiet_cmd_modules_builtin = GEN $@ + cmd_modules_builtin = \ + tr '\0' '\n' < $< | \ + sed -n 's/^[[:alnum:]:_]*\.file=//p' | \ + tr ' ' '\n' | uniq | sed -e 's:^:kernel/:' -e 's/$$/.ko/' > $@ + +targets += modules.builtin +modules.builtin: modules.builtin.modinfo FORCE + $(call if_changed,modules_builtin) + # Add FORCE to the prequisites of a target to force it to be always rebuilt. # --------------------------------------------------------------------------- diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 2782c5d1518b..e3d42202e54c 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -214,13 +214,6 @@ if [ "$1" = "clean" ]; then exit 0 fi -info MODINFO modules.builtin.modinfo -${OBJCOPY} -j .modinfo -O binary vmlinux.o modules.builtin.modinfo -info GEN modules.builtin -# The second line aids cases where multiple modules share the same object. -tr '\0' '\n' < modules.builtin.modinfo | sed -n 's/^[[:alnum:]:_]*\.file=//p' | - tr ' ' '\n' | uniq | sed -e 's:^:kernel/:' -e 's/$/.ko/' > modules.builtin - if is_enabled CONFIG_MODULES; then ${MAKE} -f "${srctree}/scripts/Makefile.vmlinux" .vmlinux.export.o fi -- cgit v1.2.3-59-g8ed1b From 5d4aeffbf7092b6bd7b2de71c2cd6fa14dffbad5 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 28 Sep 2022 15:39:41 +0900 Subject: kbuild: rebuild .vmlinux.export.o when its prerequisite is updated When include/linux/export-internal.h is updated, .vmlinux.export.o must be rebuilt, but it does not happen because its rule is hidden behind scripts/link-vmlinux.sh. Move it out of the shell script, so that Make can see the dependency between vmlinux and .vmlinux.export.o. Move the vmlinux rule to scripts/Makefile.vmlinux. Signed-off-by: Masahiro Yamada --- Makefile | 18 +++++------------- scripts/Makefile.vmlinux | 21 ++++++++++++++++++++- scripts/link-vmlinux.sh | 5 ----- 3 files changed, 25 insertions(+), 19 deletions(-) (limited to 'scripts') diff --git a/Makefile b/Makefile index 2fcbd753cb27..f10a27c09d88 100644 --- a/Makefile +++ b/Makefile @@ -502,7 +502,7 @@ AFLAGS_MODULE = LDFLAGS_MODULE = CFLAGS_KERNEL = AFLAGS_KERNEL = -LDFLAGS_vmlinux = +export LDFLAGS_vmlinux = # Use USERINCLUDE when you must reference the UAPI directories only. USERINCLUDE := \ @@ -1160,17 +1160,9 @@ vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS) vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o @: -ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink) - -# Final link of vmlinux with optional arch pass after final link -cmd_link-vmlinux = \ - $(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)"; \ - $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true) - -vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) modpost FORCE - +$(call if_changed_dep,link-vmlinux) - -targets += vmlinux +PHONY += vmlinux +vmlinux: vmlinux.o $(KBUILD_LDS) modpost + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux # The actual objects are generated when descending, # make sure no implicit rule kicks in @@ -1501,7 +1493,7 @@ endif # CONFIG_MODULES # Directories & files removed with 'make clean' CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \ modules.builtin modules.builtin.modinfo modules.nsdeps \ - compile_commands.json .thinlto-cache .vmlinux.objs + compile_commands.json .thinlto-cache .vmlinux.objs .vmlinux.export.c # Directories & files removed with 'make mrproper' MRPROPER_FILES += include/config include/generated \ diff --git a/scripts/Makefile.vmlinux b/scripts/Makefile.vmlinux index 7a63abf22399..49946cb96844 100644 --- a/scripts/Makefile.vmlinux +++ b/scripts/Makefile.vmlinux @@ -1,18 +1,37 @@ # SPDX-License-Identifier: GPL-2.0-only +PHONY := __default +__default: vmlinux + include include/config/auto.conf include $(srctree)/scripts/Kbuild.include # for c_flags include $(srctree)/scripts/Makefile.lib +targets := + quiet_cmd_cc_o_c = CC $@ cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< %.o: %.c FORCE $(call if_changed_dep,cc_o_c) -targets := $(MAKECMDGOALS) +ifdef CONFIG_MODULES +targets += .vmlinux.export.o +vmlinux: .vmlinux.export.o +endif + +ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink) + +# Final link of vmlinux with optional arch pass after final link +cmd_link_vmlinux = \ + $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)"; \ + $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true) + +targets += vmlinux +vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) FORCE + +$(call if_changed_dep,link_vmlinux) # Add FORCE to the prequisites of a target to force it to be always rebuilt. # --------------------------------------------------------------------------- diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index e3d42202e54c..918470d768e9 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -199,7 +199,6 @@ cleanup() rm -f System.map rm -f vmlinux rm -f vmlinux.map - rm -f .vmlinux.export.c } # Use "make V=1" to debug this script @@ -214,10 +213,6 @@ if [ "$1" = "clean" ]; then exit 0 fi -if is_enabled CONFIG_MODULES; then - ${MAKE} -f "${srctree}/scripts/Makefile.vmlinux" .vmlinux.export.o -fi - ${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init init/version-timestamp.o btf_vmlinux_bin_o="" -- cgit v1.2.3-59-g8ed1b From f80be4571b19b9fd8dd1528cd2a2f123aff51f70 Mon Sep 17 00:00:00 2001 From: Alexander Potapenko Date: Thu, 15 Sep 2022 17:03:45 +0200 Subject: kmsan: add KMSAN runtime core MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit For each memory location KernelMemorySanitizer maintains two types of metadata: 1. The so-called shadow of that location - а byte:byte mapping describing whether or not individual bits of memory are initialized (shadow is 0) or not (shadow is 1). 2. The origins of that location - а 4-byte:4-byte mapping containing 4-byte IDs of the stack traces where uninitialized values were created. Each struct page now contains pointers to two struct pages holding KMSAN metadata (shadow and origins) for the original struct page. Utility routines in mm/kmsan/core.c and mm/kmsan/shadow.c handle the metadata creation, addressing, copying and checking. mm/kmsan/report.c performs error reporting in the cases an uninitialized value is used in a way that leads to undefined behavior. KMSAN compiler instrumentation is responsible for tracking the metadata along with the kernel memory. mm/kmsan/instrumentation.c provides the implementation for instrumentation hooks that are called from files compiled with -fsanitize=kernel-memory. To aid parameter passing (also done at instrumentation level), each task_struct now contains a struct kmsan_task_state used to track the metadata of function parameters and return values for that task. Finally, this patch provides CONFIG_KMSAN that enables KMSAN, and declares CFLAGS_KMSAN, which are applied to files compiled with KMSAN. The KMSAN_SANITIZE:=n Makefile directive can be used to completely disable KMSAN instrumentation for certain files. Similarly, KMSAN_ENABLE_CHECKS:=n disables KMSAN checks and makes newly created stack memory initialized. Users can also use functions from include/linux/kmsan-checks.h to mark certain memory regions as uninitialized or initialized (this is called "poisoning" and "unpoisoning") or check that a particular region is initialized. Link: https://lkml.kernel.org/r/20220915150417.722975-12-glider@google.com Signed-off-by: Alexander Potapenko Acked-by: Marco Elver Cc: Alexander Viro Cc: Alexei Starovoitov Cc: Andrey Konovalov Cc: Andrey Konovalov Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Borislav Petkov Cc: Christoph Hellwig Cc: Christoph Lameter Cc: David Rientjes Cc: Dmitry Vyukov Cc: Eric Biggers Cc: Eric Biggers Cc: Eric Dumazet Cc: Greg Kroah-Hartman Cc: Herbert Xu Cc: Ilya Leoshkevich Cc: Ingo Molnar Cc: Jens Axboe Cc: Joonsoo Kim Cc: Kees Cook Cc: Mark Rutland Cc: Matthew Wilcox Cc: Michael S. Tsirkin Cc: Pekka Enberg Cc: Peter Zijlstra Cc: Petr Mladek Cc: Stephen Rothwell Cc: Steven Rostedt Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Vegard Nossum Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- Makefile | 1 + include/linux/kmsan-checks.h | 64 +++++++ include/linux/kmsan_types.h | 35 ++++ include/linux/mm_types.h | 12 ++ include/linux/sched.h | 5 + lib/Kconfig.debug | 1 + lib/Kconfig.kmsan | 50 +++++ mm/Makefile | 1 + mm/kmsan/Makefile | 23 +++ mm/kmsan/core.c | 440 +++++++++++++++++++++++++++++++++++++++++++ mm/kmsan/hooks.c | 66 +++++++ mm/kmsan/instrumentation.c | 307 ++++++++++++++++++++++++++++++ mm/kmsan/kmsan.h | 204 ++++++++++++++++++++ mm/kmsan/report.c | 219 +++++++++++++++++++++ mm/kmsan/shadow.c | 147 +++++++++++++++ scripts/Makefile.kmsan | 8 + scripts/Makefile.lib | 9 + 17 files changed, 1592 insertions(+) create mode 100644 include/linux/kmsan-checks.h create mode 100644 include/linux/kmsan_types.h create mode 100644 lib/Kconfig.kmsan create mode 100644 mm/kmsan/Makefile create mode 100644 mm/kmsan/core.c create mode 100644 mm/kmsan/hooks.c create mode 100644 mm/kmsan/instrumentation.c create mode 100644 mm/kmsan/kmsan.h create mode 100644 mm/kmsan/report.c create mode 100644 mm/kmsan/shadow.c create mode 100644 scripts/Makefile.kmsan (limited to 'scripts') diff --git a/Makefile b/Makefile index 952d354069a4..c9f37d25ea63 100644 --- a/Makefile +++ b/Makefile @@ -1015,6 +1015,7 @@ include-y := scripts/Makefile.extrawarn include-$(CONFIG_DEBUG_INFO) += scripts/Makefile.debug include-$(CONFIG_KASAN) += scripts/Makefile.kasan include-$(CONFIG_KCSAN) += scripts/Makefile.kcsan +include-$(CONFIG_KMSAN) += scripts/Makefile.kmsan include-$(CONFIG_UBSAN) += scripts/Makefile.ubsan include-$(CONFIG_KCOV) += scripts/Makefile.kcov include-$(CONFIG_RANDSTRUCT) += scripts/Makefile.randstruct diff --git a/include/linux/kmsan-checks.h b/include/linux/kmsan-checks.h new file mode 100644 index 000000000000..a6522a0c28df --- /dev/null +++ b/include/linux/kmsan-checks.h @@ -0,0 +1,64 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * KMSAN checks to be used for one-off annotations in subsystems. + * + * Copyright (C) 2017-2022 Google LLC + * Author: Alexander Potapenko + * + */ + +#ifndef _LINUX_KMSAN_CHECKS_H +#define _LINUX_KMSAN_CHECKS_H + +#include + +#ifdef CONFIG_KMSAN + +/** + * kmsan_poison_memory() - Mark the memory range as uninitialized. + * @address: address to start with. + * @size: size of buffer to poison. + * @flags: GFP flags for allocations done by this function. + * + * Until other data is written to this range, KMSAN will treat it as + * uninitialized. Error reports for this memory will reference the call site of + * kmsan_poison_memory() as origin. + */ +void kmsan_poison_memory(const void *address, size_t size, gfp_t flags); + +/** + * kmsan_unpoison_memory() - Mark the memory range as initialized. + * @address: address to start with. + * @size: size of buffer to unpoison. + * + * Until other data is written to this range, KMSAN will treat it as + * initialized. + */ +void kmsan_unpoison_memory(const void *address, size_t size); + +/** + * kmsan_check_memory() - Check the memory range for being initialized. + * @address: address to start with. + * @size: size of buffer to check. + * + * If any piece of the given range is marked as uninitialized, KMSAN will report + * an error. + */ +void kmsan_check_memory(const void *address, size_t size); + +#else + +static inline void kmsan_poison_memory(const void *address, size_t size, + gfp_t flags) +{ +} +static inline void kmsan_unpoison_memory(const void *address, size_t size) +{ +} +static inline void kmsan_check_memory(const void *address, size_t size) +{ +} + +#endif + +#endif /* _LINUX_KMSAN_CHECKS_H */ diff --git a/include/linux/kmsan_types.h b/include/linux/kmsan_types.h new file mode 100644 index 000000000000..8bfa6c98176d --- /dev/null +++ b/include/linux/kmsan_types.h @@ -0,0 +1,35 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * A minimal header declaring types added by KMSAN to existing kernel structs. + * + * Copyright (C) 2017-2022 Google LLC + * Author: Alexander Potapenko + * + */ +#ifndef _LINUX_KMSAN_TYPES_H +#define _LINUX_KMSAN_TYPES_H + +/* These constants are defined in the MSan LLVM instrumentation pass. */ +#define KMSAN_RETVAL_SIZE 800 +#define KMSAN_PARAM_SIZE 800 + +struct kmsan_context_state { + char param_tls[KMSAN_PARAM_SIZE]; + char retval_tls[KMSAN_RETVAL_SIZE]; + char va_arg_tls[KMSAN_PARAM_SIZE]; + char va_arg_origin_tls[KMSAN_PARAM_SIZE]; + u64 va_arg_overflow_size_tls; + char param_origin_tls[KMSAN_PARAM_SIZE]; + u32 retval_origin_tls; +}; + +#undef KMSAN_PARAM_SIZE +#undef KMSAN_RETVAL_SIZE + +struct kmsan_ctx { + struct kmsan_context_state cstate; + int kmsan_in_runtime; + bool allow_reporting; +}; + +#endif /* _LINUX_KMSAN_TYPES_H */ diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 5c87d0f292a2..500e536796ca 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -224,6 +224,18 @@ struct page { not kmapped, ie. highmem) */ #endif /* WANT_PAGE_VIRTUAL */ +#ifdef CONFIG_KMSAN + /* + * KMSAN metadata for this page: + * - shadow page: every bit indicates whether the corresponding + * bit of the original page is initialized (0) or not (1); + * - origin page: every 4 bytes contain an id of the stack trace + * where the uninitialized value was created. + */ + struct page *kmsan_shadow; + struct page *kmsan_origin; +#endif + #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS int _last_cpupid; #endif diff --git a/include/linux/sched.h b/include/linux/sched.h index fbac3c19fe35..88a043f7235e 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -1362,6 +1363,10 @@ struct task_struct { #endif #endif +#ifdef CONFIG_KMSAN + struct kmsan_ctx kmsan_ctx; +#endif + #if IS_ENABLED(CONFIG_KUNIT) struct kunit *kunit_test; #endif diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 6d1544d9201e..0129bee7de01 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -970,6 +970,7 @@ config DEBUG_STACKOVERFLOW source "lib/Kconfig.kasan" source "lib/Kconfig.kfence" +source "lib/Kconfig.kmsan" endmenu # "Memory Debugging" diff --git a/lib/Kconfig.kmsan b/lib/Kconfig.kmsan new file mode 100644 index 000000000000..5b19dbd34d76 --- /dev/null +++ b/lib/Kconfig.kmsan @@ -0,0 +1,50 @@ +# SPDX-License-Identifier: GPL-2.0-only +config HAVE_ARCH_KMSAN + bool + +config HAVE_KMSAN_COMPILER + # Clang versions <14.0.0 also support -fsanitize=kernel-memory, but not + # all the features necessary to build the kernel with KMSAN. + depends on CC_IS_CLANG && CLANG_VERSION >= 140000 + def_bool $(cc-option,-fsanitize=kernel-memory -mllvm -msan-disable-checks=1) + +config KMSAN + bool "KMSAN: detector of uninitialized values use" + depends on HAVE_ARCH_KMSAN && HAVE_KMSAN_COMPILER + depends on SLUB && DEBUG_KERNEL && !KASAN && !KCSAN + select STACKDEPOT + select STACKDEPOT_ALWAYS_INIT + help + KernelMemorySanitizer (KMSAN) is a dynamic detector of uses of + uninitialized values in the kernel. It is based on compiler + instrumentation provided by Clang and thus requires Clang to build. + + An important note is that KMSAN is not intended for production use, + because it drastically increases kernel memory footprint and slows + the whole system down. + + See for more details. + +if KMSAN + +config HAVE_KMSAN_PARAM_RETVAL + # -fsanitize-memory-param-retval is supported only by Clang >= 14. + depends on HAVE_KMSAN_COMPILER + def_bool $(cc-option,-fsanitize=kernel-memory -fsanitize-memory-param-retval) + +config KMSAN_CHECK_PARAM_RETVAL + bool "Check for uninitialized values passed to and returned from functions" + default y + depends on HAVE_KMSAN_PARAM_RETVAL + help + If the compiler supports -fsanitize-memory-param-retval, KMSAN will + eagerly check every function parameter passed by value and every + function return value. + + Disabling KMSAN_CHECK_PARAM_RETVAL will result in tracking shadow for + function parameters and return values across function borders. This + is a more relaxed mode, but it generates more instrumentation code and + may potentially report errors in corner cases when non-instrumented + functions call instrumented ones. + +endif diff --git a/mm/Makefile b/mm/Makefile index a731d1decbb1..cc23b0052584 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -89,6 +89,7 @@ obj-$(CONFIG_SLAB) += slab.o obj-$(CONFIG_SLUB) += slub.o obj-$(CONFIG_KASAN) += kasan/ obj-$(CONFIG_KFENCE) += kfence/ +obj-$(CONFIG_KMSAN) += kmsan/ obj-$(CONFIG_FAILSLAB) += failslab.o obj-$(CONFIG_MEMTEST) += memtest.o obj-$(CONFIG_MIGRATION) += migrate.o diff --git a/mm/kmsan/Makefile b/mm/kmsan/Makefile new file mode 100644 index 000000000000..550ad8625e4f --- /dev/null +++ b/mm/kmsan/Makefile @@ -0,0 +1,23 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for KernelMemorySanitizer (KMSAN). +# +# +obj-y := core.o instrumentation.o hooks.o report.o shadow.o + +KMSAN_SANITIZE := n +KCOV_INSTRUMENT := n +UBSAN_SANITIZE := n + +# Disable instrumentation of KMSAN runtime with other tools. +CC_FLAGS_KMSAN_RUNTIME := -fno-stack-protector +CC_FLAGS_KMSAN_RUNTIME += $(call cc-option,-fno-conserve-stack) +CC_FLAGS_KMSAN_RUNTIME += -DDISABLE_BRANCH_PROFILING + +CFLAGS_REMOVE.o = $(CC_FLAGS_FTRACE) + +CFLAGS_core.o := $(CC_FLAGS_KMSAN_RUNTIME) +CFLAGS_hooks.o := $(CC_FLAGS_KMSAN_RUNTIME) +CFLAGS_instrumentation.o := $(CC_FLAGS_KMSAN_RUNTIME) +CFLAGS_report.o := $(CC_FLAGS_KMSAN_RUNTIME) +CFLAGS_shadow.o := $(CC_FLAGS_KMSAN_RUNTIME) diff --git a/mm/kmsan/core.c b/mm/kmsan/core.c new file mode 100644 index 000000000000..5330138fda5b --- /dev/null +++ b/mm/kmsan/core.c @@ -0,0 +1,440 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * KMSAN runtime library. + * + * Copyright (C) 2017-2022 Google LLC + * Author: Alexander Potapenko + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../slab.h" +#include "kmsan.h" + +bool kmsan_enabled __read_mostly; + +/* + * Per-CPU KMSAN context to be used in interrupts, where current->kmsan is + * unavaliable. + */ +DEFINE_PER_CPU(struct kmsan_ctx, kmsan_percpu_ctx); + +void kmsan_internal_poison_memory(void *address, size_t size, gfp_t flags, + unsigned int poison_flags) +{ + u32 extra_bits = + kmsan_extra_bits(/*depth*/ 0, poison_flags & KMSAN_POISON_FREE); + bool checked = poison_flags & KMSAN_POISON_CHECK; + depot_stack_handle_t handle; + + handle = kmsan_save_stack_with_flags(flags, extra_bits); + kmsan_internal_set_shadow_origin(address, size, -1, handle, checked); +} + +void kmsan_internal_unpoison_memory(void *address, size_t size, bool checked) +{ + kmsan_internal_set_shadow_origin(address, size, 0, 0, checked); +} + +depot_stack_handle_t kmsan_save_stack_with_flags(gfp_t flags, + unsigned int extra) +{ + unsigned long entries[KMSAN_STACK_DEPTH]; + unsigned int nr_entries; + + nr_entries = stack_trace_save(entries, KMSAN_STACK_DEPTH, 0); + + /* Don't sleep (see might_sleep_if() in __alloc_pages_nodemask()). */ + flags &= ~__GFP_DIRECT_RECLAIM; + + return __stack_depot_save(entries, nr_entries, extra, flags, true); +} + +/* Copy the metadata following the memmove() behavior. */ +void kmsan_internal_memmove_metadata(void *dst, void *src, size_t n) +{ + depot_stack_handle_t old_origin = 0, new_origin = 0; + int src_slots, dst_slots, i, iter, step, skip_bits; + depot_stack_handle_t *origin_src, *origin_dst; + void *shadow_src, *shadow_dst; + u32 *align_shadow_src, shadow; + bool backwards; + + shadow_dst = kmsan_get_metadata(dst, KMSAN_META_SHADOW); + if (!shadow_dst) + return; + KMSAN_WARN_ON(!kmsan_metadata_is_contiguous(dst, n)); + + shadow_src = kmsan_get_metadata(src, KMSAN_META_SHADOW); + if (!shadow_src) { + /* + * @src is untracked: zero out destination shadow, ignore the + * origins, we're done. + */ + __memset(shadow_dst, 0, n); + return; + } + KMSAN_WARN_ON(!kmsan_metadata_is_contiguous(src, n)); + + __memmove(shadow_dst, shadow_src, n); + + origin_dst = kmsan_get_metadata(dst, KMSAN_META_ORIGIN); + origin_src = kmsan_get_metadata(src, KMSAN_META_ORIGIN); + KMSAN_WARN_ON(!origin_dst || !origin_src); + src_slots = (ALIGN((u64)src + n, KMSAN_ORIGIN_SIZE) - + ALIGN_DOWN((u64)src, KMSAN_ORIGIN_SIZE)) / + KMSAN_ORIGIN_SIZE; + dst_slots = (ALIGN((u64)dst + n, KMSAN_ORIGIN_SIZE) - + ALIGN_DOWN((u64)dst, KMSAN_ORIGIN_SIZE)) / + KMSAN_ORIGIN_SIZE; + KMSAN_WARN_ON((src_slots < 1) || (dst_slots < 1)); + KMSAN_WARN_ON((src_slots - dst_slots > 1) || + (dst_slots - src_slots < -1)); + + backwards = dst > src; + i = backwards ? min(src_slots, dst_slots) - 1 : 0; + iter = backwards ? -1 : 1; + + align_shadow_src = + (u32 *)ALIGN_DOWN((u64)shadow_src, KMSAN_ORIGIN_SIZE); + for (step = 0; step < min(src_slots, dst_slots); step++, i += iter) { + KMSAN_WARN_ON(i < 0); + shadow = align_shadow_src[i]; + if (i == 0) { + /* + * If @src isn't aligned on KMSAN_ORIGIN_SIZE, don't + * look at the first @src % KMSAN_ORIGIN_SIZE bytes + * of the first shadow slot. + */ + skip_bits = ((u64)src % KMSAN_ORIGIN_SIZE) * 8; + shadow = (shadow >> skip_bits) << skip_bits; + } + if (i == src_slots - 1) { + /* + * If @src + n isn't aligned on + * KMSAN_ORIGIN_SIZE, don't look at the last + * (@src + n) % KMSAN_ORIGIN_SIZE bytes of the + * last shadow slot. + */ + skip_bits = (((u64)src + n) % KMSAN_ORIGIN_SIZE) * 8; + shadow = (shadow << skip_bits) >> skip_bits; + } + /* + * Overwrite the origin only if the corresponding + * shadow is nonempty. + */ + if (origin_src[i] && (origin_src[i] != old_origin) && shadow) { + old_origin = origin_src[i]; + new_origin = kmsan_internal_chain_origin(old_origin); + /* + * kmsan_internal_chain_origin() may return + * NULL, but we don't want to lose the previous + * origin value. + */ + if (!new_origin) + new_origin = old_origin; + } + if (shadow) + origin_dst[i] = new_origin; + else + origin_dst[i] = 0; + } + /* + * If dst_slots is greater than src_slots (i.e. + * dst_slots == src_slots + 1), there is an extra origin slot at the + * beginning or end of the destination buffer, for which we take the + * origin from the previous slot. + * This is only done if the part of the source shadow corresponding to + * slot is non-zero. + * + * E.g. if we copy 8 aligned bytes that are marked as uninitialized + * and have origins o111 and o222, to an unaligned buffer with offset 1, + * these two origins are copied to three origin slots, so one of then + * needs to be duplicated, depending on the copy direction (@backwards) + * + * src shadow: |uuuu|uuuu|....| + * src origin: |o111|o222|....| + * + * backwards = 0: + * dst shadow: |.uuu|uuuu|u...| + * dst origin: |....|o111|o222| - fill the empty slot with o111 + * backwards = 1: + * dst shadow: |.uuu|uuuu|u...| + * dst origin: |o111|o222|....| - fill the empty slot with o222 + */ + if (src_slots < dst_slots) { + if (backwards) { + shadow = align_shadow_src[src_slots - 1]; + skip_bits = (((u64)dst + n) % KMSAN_ORIGIN_SIZE) * 8; + shadow = (shadow << skip_bits) >> skip_bits; + if (shadow) + /* src_slots > 0, therefore dst_slots is at least 2 */ + origin_dst[dst_slots - 1] = + origin_dst[dst_slots - 2]; + } else { + shadow = align_shadow_src[0]; + skip_bits = ((u64)dst % KMSAN_ORIGIN_SIZE) * 8; + shadow = (shadow >> skip_bits) << skip_bits; + if (shadow) + origin_dst[0] = origin_dst[1]; + } + } +} + +depot_stack_handle_t kmsan_internal_chain_origin(depot_stack_handle_t id) +{ + unsigned long entries[3]; + u32 extra_bits; + int depth; + bool uaf; + + if (!id) + return id; + /* + * Make sure we have enough spare bits in @id to hold the UAF bit and + * the chain depth. + */ + BUILD_BUG_ON( + (1 << STACK_DEPOT_EXTRA_BITS) <= (KMSAN_MAX_ORIGIN_DEPTH << 1)); + + extra_bits = stack_depot_get_extra_bits(id); + depth = kmsan_depth_from_eb(extra_bits); + uaf = kmsan_uaf_from_eb(extra_bits); + + /* + * Stop chaining origins once the depth reached KMSAN_MAX_ORIGIN_DEPTH. + * This mostly happens in the case structures with uninitialized padding + * are copied around many times. Origin chains for such structures are + * usually periodic, and it does not make sense to fully store them. + */ + if (depth == KMSAN_MAX_ORIGIN_DEPTH) + return id; + + depth++; + extra_bits = kmsan_extra_bits(depth, uaf); + + entries[0] = KMSAN_CHAIN_MAGIC_ORIGIN; + entries[1] = kmsan_save_stack_with_flags(GFP_ATOMIC, 0); + entries[2] = id; + /* + * @entries is a local var in non-instrumented code, so KMSAN does not + * know it is initialized. Explicitly unpoison it to avoid false + * positives when __stack_depot_save() passes it to instrumented code. + */ + kmsan_internal_unpoison_memory(entries, sizeof(entries), false); + return __stack_depot_save(entries, ARRAY_SIZE(entries), extra_bits, + GFP_ATOMIC, true); +} + +void kmsan_internal_set_shadow_origin(void *addr, size_t size, int b, + u32 origin, bool checked) +{ + u64 address = (u64)addr; + void *shadow_start; + u32 *origin_start; + size_t pad = 0; + + KMSAN_WARN_ON(!kmsan_metadata_is_contiguous(addr, size)); + shadow_start = kmsan_get_metadata(addr, KMSAN_META_SHADOW); + if (!shadow_start) { + /* + * kmsan_metadata_is_contiguous() is true, so either all shadow + * and origin pages are NULL, or all are non-NULL. + */ + if (checked) { + pr_err("%s: not memsetting %ld bytes starting at %px, because the shadow is NULL\n", + __func__, size, addr); + KMSAN_WARN_ON(true); + } + return; + } + __memset(shadow_start, b, size); + + if (!IS_ALIGNED(address, KMSAN_ORIGIN_SIZE)) { + pad = address % KMSAN_ORIGIN_SIZE; + address -= pad; + size += pad; + } + size = ALIGN(size, KMSAN_ORIGIN_SIZE); + origin_start = + (u32 *)kmsan_get_metadata((void *)address, KMSAN_META_ORIGIN); + + for (int i = 0; i < size / KMSAN_ORIGIN_SIZE; i++) + origin_start[i] = origin; +} + +struct page *kmsan_vmalloc_to_page_or_null(void *vaddr) +{ + struct page *page; + + if (!kmsan_internal_is_vmalloc_addr(vaddr) && + !kmsan_internal_is_module_addr(vaddr)) + return NULL; + page = vmalloc_to_page(vaddr); + if (pfn_valid(page_to_pfn(page))) + return page; + else + return NULL; +} + +void kmsan_internal_check_memory(void *addr, size_t size, const void *user_addr, + int reason) +{ + depot_stack_handle_t cur_origin = 0, new_origin = 0; + unsigned long addr64 = (unsigned long)addr; + depot_stack_handle_t *origin = NULL; + unsigned char *shadow = NULL; + int cur_off_start = -1; + int chunk_size; + size_t pos = 0; + + if (!size) + return; + KMSAN_WARN_ON(!kmsan_metadata_is_contiguous(addr, size)); + while (pos < size) { + chunk_size = min(size - pos, + PAGE_SIZE - ((addr64 + pos) % PAGE_SIZE)); + shadow = kmsan_get_metadata((void *)(addr64 + pos), + KMSAN_META_SHADOW); + if (!shadow) { + /* + * This page is untracked. If there were uninitialized + * bytes before, report them. + */ + if (cur_origin) { + kmsan_enter_runtime(); + kmsan_report(cur_origin, addr, size, + cur_off_start, pos - 1, user_addr, + reason); + kmsan_leave_runtime(); + } + cur_origin = 0; + cur_off_start = -1; + pos += chunk_size; + continue; + } + for (int i = 0; i < chunk_size; i++) { + if (!shadow[i]) { + /* + * This byte is unpoisoned. If there were + * poisoned bytes before, report them. + */ + if (cur_origin) { + kmsan_enter_runtime(); + kmsan_report(cur_origin, addr, size, + cur_off_start, pos + i - 1, + user_addr, reason); + kmsan_leave_runtime(); + } + cur_origin = 0; + cur_off_start = -1; + continue; + } + origin = kmsan_get_metadata((void *)(addr64 + pos + i), + KMSAN_META_ORIGIN); + KMSAN_WARN_ON(!origin); + new_origin = *origin; + /* + * Encountered new origin - report the previous + * uninitialized range. + */ + if (cur_origin != new_origin) { + if (cur_origin) { + kmsan_enter_runtime(); + kmsan_report(cur_origin, addr, size, + cur_off_start, pos + i - 1, + user_addr, reason); + kmsan_leave_runtime(); + } + cur_origin = new_origin; + cur_off_start = pos + i; + } + } + pos += chunk_size; + } + KMSAN_WARN_ON(pos != size); + if (cur_origin) { + kmsan_enter_runtime(); + kmsan_report(cur_origin, addr, size, cur_off_start, pos - 1, + user_addr, reason); + kmsan_leave_runtime(); + } +} + +bool kmsan_metadata_is_contiguous(void *addr, size_t size) +{ + char *cur_shadow = NULL, *next_shadow = NULL, *cur_origin = NULL, + *next_origin = NULL; + u64 cur_addr = (u64)addr, next_addr = cur_addr + PAGE_SIZE; + depot_stack_handle_t *origin_p; + bool all_untracked = false; + + if (!size) + return true; + + /* The whole range belongs to the same page. */ + if (ALIGN_DOWN(cur_addr + size - 1, PAGE_SIZE) == + ALIGN_DOWN(cur_addr, PAGE_SIZE)) + return true; + + cur_shadow = kmsan_get_metadata((void *)cur_addr, /*is_origin*/ false); + if (!cur_shadow) + all_untracked = true; + cur_origin = kmsan_get_metadata((void *)cur_addr, /*is_origin*/ true); + if (all_untracked && cur_origin) + goto report; + + for (; next_addr < (u64)addr + size; + cur_addr = next_addr, cur_shadow = next_shadow, + cur_origin = next_origin, next_addr += PAGE_SIZE) { + next_shadow = kmsan_get_metadata((void *)next_addr, false); + next_origin = kmsan_get_metadata((void *)next_addr, true); + if (all_untracked) { + if (next_shadow || next_origin) + goto report; + if (!next_shadow && !next_origin) + continue; + } + if (((u64)cur_shadow == ((u64)next_shadow - PAGE_SIZE)) && + ((u64)cur_origin == ((u64)next_origin - PAGE_SIZE))) + continue; + goto report; + } + return true; + +report: + pr_err("%s: attempting to access two shadow page ranges.\n", __func__); + pr_err("Access of size %ld at %px.\n", size, addr); + pr_err("Addresses belonging to different ranges: %px and %px\n", + (void *)cur_addr, (void *)next_addr); + pr_err("page[0].shadow: %px, page[1].shadow: %px\n", cur_shadow, + next_shadow); + pr_err("page[0].origin: %px, page[1].origin: %px\n", cur_origin, + next_origin); + origin_p = kmsan_get_metadata(addr, KMSAN_META_ORIGIN); + if (origin_p) { + pr_err("Origin: %08x\n", *origin_p); + kmsan_print_origin(*origin_p); + } else { + pr_err("Origin: unavailable\n"); + } + return false; +} diff --git a/mm/kmsan/hooks.c b/mm/kmsan/hooks.c new file mode 100644 index 000000000000..4ac62fa67a02 --- /dev/null +++ b/mm/kmsan/hooks.c @@ -0,0 +1,66 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * KMSAN hooks for kernel subsystems. + * + * These functions handle creation of KMSAN metadata for memory allocations. + * + * Copyright (C) 2018-2022 Google LLC + * Author: Alexander Potapenko + * + */ + +#include +#include +#include +#include +#include +#include + +#include "../internal.h" +#include "../slab.h" +#include "kmsan.h" + +/* + * Instrumented functions shouldn't be called under + * kmsan_enter_runtime()/kmsan_leave_runtime(), because this will lead to + * skipping effects of functions like memset() inside instrumented code. + */ + +/* Functions from kmsan-checks.h follow. */ +void kmsan_poison_memory(const void *address, size_t size, gfp_t flags) +{ + if (!kmsan_enabled || kmsan_in_runtime()) + return; + kmsan_enter_runtime(); + /* The users may want to poison/unpoison random memory. */ + kmsan_internal_poison_memory((void *)address, size, flags, + KMSAN_POISON_NOCHECK); + kmsan_leave_runtime(); +} +EXPORT_SYMBOL(kmsan_poison_memory); + +void kmsan_unpoison_memory(const void *address, size_t size) +{ + unsigned long ua_flags; + + if (!kmsan_enabled || kmsan_in_runtime()) + return; + + ua_flags = user_access_save(); + kmsan_enter_runtime(); + /* The users may want to poison/unpoison random memory. */ + kmsan_internal_unpoison_memory((void *)address, size, + KMSAN_POISON_NOCHECK); + kmsan_leave_runtime(); + user_access_restore(ua_flags); +} +EXPORT_SYMBOL(kmsan_unpoison_memory); + +void kmsan_check_memory(const void *addr, size_t size) +{ + if (!kmsan_enabled) + return; + return kmsan_internal_check_memory((void *)addr, size, /*user_addr*/ 0, + REASON_ANY); +} +EXPORT_SYMBOL(kmsan_check_memory); diff --git a/mm/kmsan/instrumentation.c b/mm/kmsan/instrumentation.c new file mode 100644 index 000000000000..280d15413268 --- /dev/null +++ b/mm/kmsan/instrumentation.c @@ -0,0 +1,307 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * KMSAN compiler API. + * + * This file implements __msan_XXX hooks that Clang inserts into the code + * compiled with -fsanitize=kernel-memory. + * See Documentation/dev-tools/kmsan.rst for more information on how KMSAN + * instrumentation works. + * + * Copyright (C) 2017-2022 Google LLC + * Author: Alexander Potapenko + * + */ + +#include "kmsan.h" +#include +#include +#include + +static inline bool is_bad_asm_addr(void *addr, uintptr_t size, bool is_store) +{ + if ((u64)addr < TASK_SIZE) + return true; + if (!kmsan_get_metadata(addr, KMSAN_META_SHADOW)) + return true; + return false; +} + +static inline struct shadow_origin_ptr +get_shadow_origin_ptr(void *addr, u64 size, bool store) +{ + unsigned long ua_flags = user_access_save(); + struct shadow_origin_ptr ret; + + ret = kmsan_get_shadow_origin_ptr(addr, size, store); + user_access_restore(ua_flags); + return ret; +} + +/* Get shadow and origin pointers for a memory load with non-standard size. */ +struct shadow_origin_ptr __msan_metadata_ptr_for_load_n(void *addr, + uintptr_t size) +{ + return get_shadow_origin_ptr(addr, size, /*store*/ false); +} +EXPORT_SYMBOL(__msan_metadata_ptr_for_load_n); + +/* Get shadow and origin pointers for a memory store with non-standard size. */ +struct shadow_origin_ptr __msan_metadata_ptr_for_store_n(void *addr, + uintptr_t size) +{ + return get_shadow_origin_ptr(addr, size, /*store*/ true); +} +EXPORT_SYMBOL(__msan_metadata_ptr_for_store_n); + +/* + * Declare functions that obtain shadow/origin pointers for loads and stores + * with fixed size. + */ +#define DECLARE_METADATA_PTR_GETTER(size) \ + struct shadow_origin_ptr __msan_metadata_ptr_for_load_##size( \ + void *addr) \ + { \ + return get_shadow_origin_ptr(addr, size, /*store*/ false); \ + } \ + EXPORT_SYMBOL(__msan_metadata_ptr_for_load_##size); \ + struct shadow_origin_ptr __msan_metadata_ptr_for_store_##size( \ + void *addr) \ + { \ + return get_shadow_origin_ptr(addr, size, /*store*/ true); \ + } \ + EXPORT_SYMBOL(__msan_metadata_ptr_for_store_##size) + +DECLARE_METADATA_PTR_GETTER(1); +DECLARE_METADATA_PTR_GETTER(2); +DECLARE_METADATA_PTR_GETTER(4); +DECLARE_METADATA_PTR_GETTER(8); + +/* + * Handle a memory store performed by inline assembly. KMSAN conservatively + * attempts to unpoison the outputs of asm() directives to prevent false + * positives caused by missed stores. + */ +void __msan_instrument_asm_store(void *addr, uintptr_t size) +{ + unsigned long ua_flags; + + if (!kmsan_enabled || kmsan_in_runtime()) + return; + + ua_flags = user_access_save(); + /* + * Most of the accesses are below 32 bytes. The two exceptions so far + * are clwb() (64 bytes) and FPU state (512 bytes). + * It's unlikely that the assembly will touch more than 512 bytes. + */ + if (size > 512) { + WARN_ONCE(1, "assembly store size too big: %ld\n", size); + size = 8; + } + if (is_bad_asm_addr(addr, size, /*is_store*/ true)) { + user_access_restore(ua_flags); + return; + } + kmsan_enter_runtime(); + /* Unpoisoning the memory on best effort. */ + kmsan_internal_unpoison_memory(addr, size, /*checked*/ false); + kmsan_leave_runtime(); + user_access_restore(ua_flags); +} +EXPORT_SYMBOL(__msan_instrument_asm_store); + +/* + * KMSAN instrumentation pass replaces LLVM memcpy, memmove and memset + * intrinsics with calls to respective __msan_ functions. We use + * get_param0_metadata() and set_retval_metadata() to store the shadow/origin + * values for the destination argument of these functions and use them for the + * functions' return values. + */ +static inline void get_param0_metadata(u64 *shadow, + depot_stack_handle_t *origin) +{ + struct kmsan_ctx *ctx = kmsan_get_context(); + + *shadow = *(u64 *)(ctx->cstate.param_tls); + *origin = ctx->cstate.param_origin_tls[0]; +} + +static inline void set_retval_metadata(u64 shadow, depot_stack_handle_t origin) +{ + struct kmsan_ctx *ctx = kmsan_get_context(); + + *(u64 *)(ctx->cstate.retval_tls) = shadow; + ctx->cstate.retval_origin_tls = origin; +} + +/* Handle llvm.memmove intrinsic. */ +void *__msan_memmove(void *dst, const void *src, uintptr_t n) +{ + depot_stack_handle_t origin; + void *result; + u64 shadow; + + get_param0_metadata(&shadow, &origin); + result = __memmove(dst, src, n); + if (!n) + /* Some people call memmove() with zero length. */ + return result; + if (!kmsan_enabled || kmsan_in_runtime()) + return result; + + kmsan_enter_runtime(); + kmsan_internal_memmove_metadata(dst, (void *)src, n); + kmsan_leave_runtime(); + + set_retval_metadata(shadow, origin); + return result; +} +EXPORT_SYMBOL(__msan_memmove); + +/* Handle llvm.memcpy intrinsic. */ +void *__msan_memcpy(void *dst, const void *src, uintptr_t n) +{ + depot_stack_handle_t origin; + void *result; + u64 shadow; + + get_param0_metadata(&shadow, &origin); + result = __memcpy(dst, src, n); + if (!n) + /* Some people call memcpy() with zero length. */ + return result; + + if (!kmsan_enabled || kmsan_in_runtime()) + return result; + + kmsan_enter_runtime(); + /* Using memmove instead of memcpy doesn't affect correctness. */ + kmsan_internal_memmove_metadata(dst, (void *)src, n); + kmsan_leave_runtime(); + + set_retval_metadata(shadow, origin); + return result; +} +EXPORT_SYMBOL(__msan_memcpy); + +/* Handle llvm.memset intrinsic. */ +void *__msan_memset(void *dst, int c, uintptr_t n) +{ + depot_stack_handle_t origin; + void *result; + u64 shadow; + + get_param0_metadata(&shadow, &origin); + result = __memset(dst, c, n); + if (!kmsan_enabled || kmsan_in_runtime()) + return result; + + kmsan_enter_runtime(); + /* + * Clang doesn't pass parameter metadata here, so it is impossible to + * use shadow of @c to set up the shadow for @dst. + */ + kmsan_internal_unpoison_memory(dst, n, /*checked*/ false); + kmsan_leave_runtime(); + + set_retval_metadata(shadow, origin); + return result; +} +EXPORT_SYMBOL(__msan_memset); + +/* + * Create a new origin from an old one. This is done when storing an + * uninitialized value to memory. When reporting an error, KMSAN unrolls and + * prints the whole chain of stores that preceded the use of this value. + */ +depot_stack_handle_t __msan_chain_origin(depot_stack_handle_t origin) +{ + depot_stack_handle_t ret = 0; + unsigned long ua_flags; + + if (!kmsan_enabled || kmsan_in_runtime()) + return ret; + + ua_flags = user_access_save(); + + /* Creating new origins may allocate memory. */ + kmsan_enter_runtime(); + ret = kmsan_internal_chain_origin(origin); + kmsan_leave_runtime(); + user_access_restore(ua_flags); + return ret; +} +EXPORT_SYMBOL(__msan_chain_origin); + +/* Poison a local variable when entering a function. */ +void __msan_poison_alloca(void *address, uintptr_t size, char *descr) +{ + depot_stack_handle_t handle; + unsigned long entries[4]; + unsigned long ua_flags; + + if (!kmsan_enabled || kmsan_in_runtime()) + return; + + ua_flags = user_access_save(); + entries[0] = KMSAN_ALLOCA_MAGIC_ORIGIN; + entries[1] = (u64)descr; + entries[2] = (u64)__builtin_return_address(0); + /* + * With frame pointers enabled, it is possible to quickly fetch the + * second frame of the caller stack without calling the unwinder. + * Without them, simply do not bother. + */ + if (IS_ENABLED(CONFIG_UNWINDER_FRAME_POINTER)) + entries[3] = (u64)__builtin_return_address(1); + else + entries[3] = 0; + + /* stack_depot_save() may allocate memory. */ + kmsan_enter_runtime(); + handle = stack_depot_save(entries, ARRAY_SIZE(entries), GFP_ATOMIC); + kmsan_leave_runtime(); + + kmsan_internal_set_shadow_origin(address, size, -1, handle, + /*checked*/ true); + user_access_restore(ua_flags); +} +EXPORT_SYMBOL(__msan_poison_alloca); + +/* Unpoison a local variable. */ +void __msan_unpoison_alloca(void *address, uintptr_t size) +{ + if (!kmsan_enabled || kmsan_in_runtime()) + return; + + kmsan_enter_runtime(); + kmsan_internal_unpoison_memory(address, size, /*checked*/ true); + kmsan_leave_runtime(); +} +EXPORT_SYMBOL(__msan_unpoison_alloca); + +/* + * Report that an uninitialized value with the given origin was used in a way + * that constituted undefined behavior. + */ +void __msan_warning(u32 origin) +{ + if (!kmsan_enabled || kmsan_in_runtime()) + return; + kmsan_enter_runtime(); + kmsan_report(origin, /*address*/ 0, /*size*/ 0, + /*off_first*/ 0, /*off_last*/ 0, /*user_addr*/ 0, + REASON_ANY); + kmsan_leave_runtime(); +} +EXPORT_SYMBOL(__msan_warning); + +/* + * At the beginning of an instrumented function, obtain the pointer to + * `struct kmsan_context_state` holding the metadata for function parameters. + */ +struct kmsan_context_state *__msan_get_context_state(void) +{ + return &kmsan_get_context()->cstate; +} +EXPORT_SYMBOL(__msan_get_context_state); diff --git a/mm/kmsan/kmsan.h b/mm/kmsan/kmsan.h new file mode 100644 index 000000000000..97d48b45dba5 --- /dev/null +++ b/mm/kmsan/kmsan.h @@ -0,0 +1,204 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Functions used by the KMSAN runtime. + * + * Copyright (C) 2017-2022 Google LLC + * Author: Alexander Potapenko + * + */ + +#ifndef __MM_KMSAN_KMSAN_H +#define __MM_KMSAN_KMSAN_H + +#include +#include +#include +#include +#include +#include +#include +#include + +#define KMSAN_ALLOCA_MAGIC_ORIGIN 0xabcd0100 +#define KMSAN_CHAIN_MAGIC_ORIGIN 0xabcd0200 + +#define KMSAN_POISON_NOCHECK 0x0 +#define KMSAN_POISON_CHECK 0x1 +#define KMSAN_POISON_FREE 0x2 + +#define KMSAN_ORIGIN_SIZE 4 +#define KMSAN_MAX_ORIGIN_DEPTH 7 + +#define KMSAN_STACK_DEPTH 64 + +#define KMSAN_META_SHADOW (false) +#define KMSAN_META_ORIGIN (true) + +extern bool kmsan_enabled; +extern int panic_on_kmsan; + +/* + * KMSAN performs a lot of consistency checks that are currently enabled by + * default. BUG_ON is normally discouraged in the kernel, unless used for + * debugging, but KMSAN itself is a debugging tool, so it makes little sense to + * recover if something goes wrong. + */ +#define KMSAN_WARN_ON(cond) \ + ({ \ + const bool __cond = WARN_ON(cond); \ + if (unlikely(__cond)) { \ + WRITE_ONCE(kmsan_enabled, false); \ + if (panic_on_kmsan) { \ + /* Can't call panic() here because */ \ + /* of uaccess checks. */ \ + BUG(); \ + } \ + } \ + __cond; \ + }) + +/* + * A pair of metadata pointers to be returned by the instrumentation functions. + */ +struct shadow_origin_ptr { + void *shadow, *origin; +}; + +struct shadow_origin_ptr kmsan_get_shadow_origin_ptr(void *addr, u64 size, + bool store); +void *kmsan_get_metadata(void *addr, bool is_origin); + +enum kmsan_bug_reason { + REASON_ANY, + REASON_COPY_TO_USER, + REASON_SUBMIT_URB, +}; + +void kmsan_print_origin(depot_stack_handle_t origin); + +/** + * kmsan_report() - Report a use of uninitialized value. + * @origin: Stack ID of the uninitialized value. + * @address: Address at which the memory access happens. + * @size: Memory access size. + * @off_first: Offset (from @address) of the first byte to be reported. + * @off_last: Offset (from @address) of the last byte to be reported. + * @user_addr: When non-NULL, denotes the userspace address to which the kernel + * is leaking data. + * @reason: Error type from enum kmsan_bug_reason. + * + * kmsan_report() prints an error message for a consequent group of bytes + * sharing the same origin. If an uninitialized value is used in a comparison, + * this function is called once without specifying the addresses. When checking + * a memory range, KMSAN may call kmsan_report() multiple times with the same + * @address, @size, @user_addr and @reason, but different @off_first and + * @off_last corresponding to different @origin values. + */ +void kmsan_report(depot_stack_handle_t origin, void *address, int size, + int off_first, int off_last, const void *user_addr, + enum kmsan_bug_reason reason); + +DECLARE_PER_CPU(struct kmsan_ctx, kmsan_percpu_ctx); + +static __always_inline struct kmsan_ctx *kmsan_get_context(void) +{ + return in_task() ? ¤t->kmsan_ctx : raw_cpu_ptr(&kmsan_percpu_ctx); +} + +/* + * When a compiler hook or KMSAN runtime function is invoked, it may make a + * call to instrumented code and eventually call itself recursively. To avoid + * that, we guard the runtime entry regions with + * kmsan_enter_runtime()/kmsan_leave_runtime() and exit the hook if + * kmsan_in_runtime() is true. + * + * Non-runtime code may occasionally get executed in nested IRQs from the + * runtime code (e.g. when called via smp_call_function_single()). Because some + * KMSAN routines may take locks (e.g. for memory allocation), we conservatively + * bail out instead of calling them. To minimize the effect of this (potentially + * missing initialization events) kmsan_in_runtime() is not checked in + * non-blocking runtime functions. + */ +static __always_inline bool kmsan_in_runtime(void) +{ + if ((hardirq_count() >> HARDIRQ_SHIFT) > 1) + return true; + return kmsan_get_context()->kmsan_in_runtime; +} + +static __always_inline void kmsan_enter_runtime(void) +{ + struct kmsan_ctx *ctx; + + ctx = kmsan_get_context(); + KMSAN_WARN_ON(ctx->kmsan_in_runtime++); +} + +static __always_inline void kmsan_leave_runtime(void) +{ + struct kmsan_ctx *ctx = kmsan_get_context(); + + KMSAN_WARN_ON(--ctx->kmsan_in_runtime); +} + +depot_stack_handle_t kmsan_save_stack(void); +depot_stack_handle_t kmsan_save_stack_with_flags(gfp_t flags, + unsigned int extra_bits); + +/* + * Pack and unpack the origin chain depth and UAF flag to/from the extra bits + * provided by the stack depot. + * The UAF flag is stored in the lowest bit, followed by the depth in the upper + * bits. + * set_dsh_extra_bits() is responsible for clamping the value. + */ +static __always_inline unsigned int kmsan_extra_bits(unsigned int depth, + bool uaf) +{ + return (depth << 1) | uaf; +} + +static __always_inline bool kmsan_uaf_from_eb(unsigned int extra_bits) +{ + return extra_bits & 1; +} + +static __always_inline unsigned int kmsan_depth_from_eb(unsigned int extra_bits) +{ + return extra_bits >> 1; +} + +/* + * kmsan_internal_ functions are supposed to be very simple and not require the + * kmsan_in_runtime() checks. + */ +void kmsan_internal_memmove_metadata(void *dst, void *src, size_t n); +void kmsan_internal_poison_memory(void *address, size_t size, gfp_t flags, + unsigned int poison_flags); +void kmsan_internal_unpoison_memory(void *address, size_t size, bool checked); +void kmsan_internal_set_shadow_origin(void *address, size_t size, int b, + u32 origin, bool checked); +depot_stack_handle_t kmsan_internal_chain_origin(depot_stack_handle_t id); + +bool kmsan_metadata_is_contiguous(void *addr, size_t size); +void kmsan_internal_check_memory(void *addr, size_t size, const void *user_addr, + int reason); + +struct page *kmsan_vmalloc_to_page_or_null(void *vaddr); + +/* + * kmsan_internal_is_module_addr() and kmsan_internal_is_vmalloc_addr() are + * non-instrumented versions of is_module_address() and is_vmalloc_addr() that + * are safe to call from KMSAN runtime without recursion. + */ +static inline bool kmsan_internal_is_module_addr(void *vaddr) +{ + return ((u64)vaddr >= MODULES_VADDR) && ((u64)vaddr < MODULES_END); +} + +static inline bool kmsan_internal_is_vmalloc_addr(void *addr) +{ + return ((u64)addr >= VMALLOC_START) && ((u64)addr < VMALLOC_END); +} + +#endif /* __MM_KMSAN_KMSAN_H */ diff --git a/mm/kmsan/report.c b/mm/kmsan/report.c new file mode 100644 index 000000000000..02736ec757f2 --- /dev/null +++ b/mm/kmsan/report.c @@ -0,0 +1,219 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * KMSAN error reporting routines. + * + * Copyright (C) 2019-2022 Google LLC + * Author: Alexander Potapenko + * + */ + +#include +#include +#include +#include +#include + +#include "kmsan.h" + +static DEFINE_RAW_SPINLOCK(kmsan_report_lock); +#define DESCR_SIZE 128 +/* Protected by kmsan_report_lock */ +static char report_local_descr[DESCR_SIZE]; +int panic_on_kmsan __read_mostly; + +#ifdef MODULE_PARAM_PREFIX +#undef MODULE_PARAM_PREFIX +#endif +#define MODULE_PARAM_PREFIX "kmsan." +module_param_named(panic, panic_on_kmsan, int, 0); + +/* + * Skip internal KMSAN frames. + */ +static int get_stack_skipnr(const unsigned long stack_entries[], + int num_entries) +{ + int len, skip; + char buf[64]; + + for (skip = 0; skip < num_entries; ++skip) { + len = scnprintf(buf, sizeof(buf), "%ps", + (void *)stack_entries[skip]); + + /* Never show __msan_* or kmsan_* functions. */ + if ((strnstr(buf, "__msan_", len) == buf) || + (strnstr(buf, "kmsan_", len) == buf)) + continue; + + /* + * No match for runtime functions -- @skip entries to skip to + * get to first frame of interest. + */ + break; + } + + return skip; +} + +/* + * Currently the descriptions of locals generated by Clang look as follows: + * ----local_name@function_name + * We want to print only the name of the local, as other information in that + * description can be confusing. + * The meaningful part of the description is copied to a global buffer to avoid + * allocating memory. + */ +static char *pretty_descr(char *descr) +{ + int pos = 0, len = strlen(descr); + + for (int i = 0; i < len; i++) { + if (descr[i] == '@') + break; + if (descr[i] == '-') + continue; + report_local_descr[pos] = descr[i]; + if (pos + 1 == DESCR_SIZE) + break; + pos++; + } + report_local_descr[pos] = 0; + return report_local_descr; +} + +void kmsan_print_origin(depot_stack_handle_t origin) +{ + unsigned long *entries = NULL, *chained_entries = NULL; + unsigned int nr_entries, chained_nr_entries, skipnr; + void *pc1 = NULL, *pc2 = NULL; + depot_stack_handle_t head; + unsigned long magic; + char *descr = NULL; + unsigned int depth; + + if (!origin) + return; + + while (true) { + nr_entries = stack_depot_fetch(origin, &entries); + depth = kmsan_depth_from_eb(stack_depot_get_extra_bits(origin)); + magic = nr_entries ? entries[0] : 0; + if ((nr_entries == 4) && (magic == KMSAN_ALLOCA_MAGIC_ORIGIN)) { + descr = (char *)entries[1]; + pc1 = (void *)entries[2]; + pc2 = (void *)entries[3]; + pr_err("Local variable %s created at:\n", + pretty_descr(descr)); + if (pc1) + pr_err(" %pSb\n", pc1); + if (pc2) + pr_err(" %pSb\n", pc2); + break; + } + if ((nr_entries == 3) && (magic == KMSAN_CHAIN_MAGIC_ORIGIN)) { + /* + * Origin chains deeper than KMSAN_MAX_ORIGIN_DEPTH are + * not stored, so the output may be incomplete. + */ + if (depth == KMSAN_MAX_ORIGIN_DEPTH) + pr_err("\n\n"); + head = entries[1]; + origin = entries[2]; + pr_err("Uninit was stored to memory at:\n"); + chained_nr_entries = + stack_depot_fetch(head, &chained_entries); + kmsan_internal_unpoison_memory( + chained_entries, + chained_nr_entries * sizeof(*chained_entries), + /*checked*/ false); + skipnr = get_stack_skipnr(chained_entries, + chained_nr_entries); + stack_trace_print(chained_entries + skipnr, + chained_nr_entries - skipnr, 0); + pr_err("\n"); + continue; + } + pr_err("Uninit was created at:\n"); + if (nr_entries) { + skipnr = get_stack_skipnr(entries, nr_entries); + stack_trace_print(entries + skipnr, nr_entries - skipnr, + 0); + } else { + pr_err("(stack is not available)\n"); + } + break; + } +} + +void kmsan_report(depot_stack_handle_t origin, void *address, int size, + int off_first, int off_last, const void *user_addr, + enum kmsan_bug_reason reason) +{ + unsigned long stack_entries[KMSAN_STACK_DEPTH]; + int num_stack_entries, skipnr; + char *bug_type = NULL; + unsigned long ua_flags; + bool is_uaf; + + if (!kmsan_enabled) + return; + if (!current->kmsan_ctx.allow_reporting) + return; + if (!origin) + return; + + current->kmsan_ctx.allow_reporting = false; + ua_flags = user_access_save(); + raw_spin_lock(&kmsan_report_lock); + pr_err("=====================================================\n"); + is_uaf = kmsan_uaf_from_eb(stack_depot_get_extra_bits(origin)); + switch (reason) { + case REASON_ANY: + bug_type = is_uaf ? "use-after-free" : "uninit-value"; + break; + case REASON_COPY_TO_USER: + bug_type = is_uaf ? "kernel-infoleak-after-free" : + "kernel-infoleak"; + break; + case REASON_SUBMIT_URB: + bug_type = is_uaf ? "kernel-usb-infoleak-after-free" : + "kernel-usb-infoleak"; + break; + } + + num_stack_entries = + stack_trace_save(stack_entries, KMSAN_STACK_DEPTH, 1); + skipnr = get_stack_skipnr(stack_entries, num_stack_entries); + + pr_err("BUG: KMSAN: %s in %pSb\n", bug_type, + (void *)stack_entries[skipnr]); + stack_trace_print(stack_entries + skipnr, num_stack_entries - skipnr, + 0); + pr_err("\n"); + + kmsan_print_origin(origin); + + if (size) { + pr_err("\n"); + if (off_first == off_last) + pr_err("Byte %d of %d is uninitialized\n", off_first, + size); + else + pr_err("Bytes %d-%d of %d are uninitialized\n", + off_first, off_last, size); + } + if (address) + pr_err("Memory access of size %d starts at %px\n", size, + address); + if (user_addr && reason == REASON_COPY_TO_USER) + pr_err("Data copied to user address %px\n", user_addr); + pr_err("\n"); + dump_stack_print_info(KERN_ERR); + pr_err("=====================================================\n"); + add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); + raw_spin_unlock(&kmsan_report_lock); + if (panic_on_kmsan) + panic("kmsan.panic set ...\n"); + user_access_restore(ua_flags); + current->kmsan_ctx.allow_reporting = true; +} diff --git a/mm/kmsan/shadow.c b/mm/kmsan/shadow.c new file mode 100644 index 000000000000..acc5279acc3b --- /dev/null +++ b/mm/kmsan/shadow.c @@ -0,0 +1,147 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * KMSAN shadow implementation. + * + * Copyright (C) 2017-2022 Google LLC + * Author: Alexander Potapenko + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../internal.h" +#include "kmsan.h" + +#define shadow_page_for(page) ((page)->kmsan_shadow) + +#define origin_page_for(page) ((page)->kmsan_origin) + +static void *shadow_ptr_for(struct page *page) +{ + return page_address(shadow_page_for(page)); +} + +static void *origin_ptr_for(struct page *page) +{ + return page_address(origin_page_for(page)); +} + +static bool page_has_metadata(struct page *page) +{ + return shadow_page_for(page) && origin_page_for(page); +} + +static void set_no_shadow_origin_page(struct page *page) +{ + shadow_page_for(page) = NULL; + origin_page_for(page) = NULL; +} + +/* + * Dummy load and store pages to be used when the real metadata is unavailable. + * There are separate pages for loads and stores, so that every load returns a + * zero, and every store doesn't affect other loads. + */ +static char dummy_load_page[PAGE_SIZE] __aligned(PAGE_SIZE); +static char dummy_store_page[PAGE_SIZE] __aligned(PAGE_SIZE); + +static unsigned long vmalloc_meta(void *addr, bool is_origin) +{ + unsigned long addr64 = (unsigned long)addr, off; + + KMSAN_WARN_ON(is_origin && !IS_ALIGNED(addr64, KMSAN_ORIGIN_SIZE)); + if (kmsan_internal_is_vmalloc_addr(addr)) { + off = addr64 - VMALLOC_START; + return off + (is_origin ? KMSAN_VMALLOC_ORIGIN_START : + KMSAN_VMALLOC_SHADOW_START); + } + if (kmsan_internal_is_module_addr(addr)) { + off = addr64 - MODULES_VADDR; + return off + (is_origin ? KMSAN_MODULES_ORIGIN_START : + KMSAN_MODULES_SHADOW_START); + } + return 0; +} + +static struct page *virt_to_page_or_null(void *vaddr) +{ + if (kmsan_virt_addr_valid(vaddr)) + return virt_to_page(vaddr); + else + return NULL; +} + +struct shadow_origin_ptr kmsan_get_shadow_origin_ptr(void *address, u64 size, + bool store) +{ + struct shadow_origin_ptr ret; + void *shadow; + + /* + * Even if we redirect this memory access to the dummy page, it will + * go out of bounds. + */ + KMSAN_WARN_ON(size > PAGE_SIZE); + + if (!kmsan_enabled) + goto return_dummy; + + KMSAN_WARN_ON(!kmsan_metadata_is_contiguous(address, size)); + shadow = kmsan_get_metadata(address, KMSAN_META_SHADOW); + if (!shadow) + goto return_dummy; + + ret.shadow = shadow; + ret.origin = kmsan_get_metadata(address, KMSAN_META_ORIGIN); + return ret; + +return_dummy: + if (store) { + /* Ignore this store. */ + ret.shadow = dummy_store_page; + ret.origin = dummy_store_page; + } else { + /* This load will return zero. */ + ret.shadow = dummy_load_page; + ret.origin = dummy_load_page; + } + return ret; +} + +/* + * Obtain the shadow or origin pointer for the given address, or NULL if there's + * none. The caller must check the return value for being non-NULL if needed. + * The return value of this function should not depend on whether we're in the + * runtime or not. + */ +void *kmsan_get_metadata(void *address, bool is_origin) +{ + u64 addr = (u64)address, pad, off; + struct page *page; + + if (is_origin && !IS_ALIGNED(addr, KMSAN_ORIGIN_SIZE)) { + pad = addr % KMSAN_ORIGIN_SIZE; + addr -= pad; + } + address = (void *)addr; + if (kmsan_internal_is_vmalloc_addr(address) || + kmsan_internal_is_module_addr(address)) + return (void *)vmalloc_meta(address, is_origin); + + page = virt_to_page_or_null(address); + if (!page) + return NULL; + if (!page_has_metadata(page)) + return NULL; + off = addr % PAGE_SIZE; + + return (is_origin ? origin_ptr_for(page) : shadow_ptr_for(page)) + off; +} diff --git a/scripts/Makefile.kmsan b/scripts/Makefile.kmsan new file mode 100644 index 000000000000..b5b0aa61322e --- /dev/null +++ b/scripts/Makefile.kmsan @@ -0,0 +1,8 @@ +# SPDX-License-Identifier: GPL-2.0 +kmsan-cflags := -fsanitize=kernel-memory + +ifdef CONFIG_KMSAN_CHECK_PARAM_RETVAL +kmsan-cflags += -fsanitize-memory-param-retval +endif + +export CFLAGS_KMSAN := $(kmsan-cflags) diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 3fb6a99e78c4..ac32429e93b7 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -157,6 +157,15 @@ _c_flags += $(if $(patsubst n%,, \ endif endif +ifeq ($(CONFIG_KMSAN),y) +_c_flags += $(if $(patsubst n%,, \ + $(KMSAN_SANITIZE_$(basetarget).o)$(KMSAN_SANITIZE)y), \ + $(CFLAGS_KMSAN)) +_c_flags += $(if $(patsubst n%,, \ + $(KMSAN_ENABLE_CHECKS_$(basetarget).o)$(KMSAN_ENABLE_CHECKS)y), \ + , -mllvm -msan-disable-checks=1) +endif + ifeq ($(CONFIG_UBSAN),y) _c_flags += $(if $(patsubst n%,, \ $(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \ -- cgit v1.2.3-59-g8ed1b From bd17e036b495bebbf07a5fc814c868e30e1dc131 Mon Sep 17 00:00:00 2001 From: Niklas Söderlund Date: Wed, 14 Sep 2022 12:02:55 +0200 Subject: checkpatch: warn for non-standard fixes tag style MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add a warning for fixes tags that does not follow community conventions. Link: https://lkml.kernel.org/r/20220914100255.1048460-1-niklas.soderlund@corigine.com Signed-off-by: Niklas Söderlund Reviewed-by: Simon Horman Reviewed-by: Louis Peens Reviewed-by: Philippe Schenker Acked-by: Dwaipayan Ray Reviewed-by: Lukas Bulwahn Acked-by: Lukas Bulwahn Acked-by: Joe Perches Signed-off-by: Andrew Morton --- Documentation/dev-tools/checkpatch.rst | 7 ++++++ scripts/checkpatch.pl | 44 ++++++++++++++++++++++++++++++++++ 2 files changed, 51 insertions(+) (limited to 'scripts') diff --git a/Documentation/dev-tools/checkpatch.rst b/Documentation/dev-tools/checkpatch.rst index b52452bc2963..c3389c6f3838 100644 --- a/Documentation/dev-tools/checkpatch.rst +++ b/Documentation/dev-tools/checkpatch.rst @@ -612,6 +612,13 @@ Commit message See: https://www.kernel.org/doc/html/latest/process/submitting-patches.html#describe-your-changes + **BAD_FIXES_TAG** + The Fixes: tag is malformed or does not follow the community conventions. + This can occur if the tag have been split into multiple lines (e.g., when + pasted in an email program with word wrapping enabled). + + See: https://www.kernel.org/doc/html/latest/process/submitting-patches.html#describe-your-changes + Comparison style ---------------- diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 18effbe1fe90..e8e0542f29f0 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -3146,6 +3146,50 @@ sub process { } } +# Check Fixes: styles is correct + if (!$in_header_lines && + $line =~ /^\s*fixes:?\s*(?:commit\s*)?[0-9a-f]{5,}\b/i) { + my $orig_commit = ""; + my $id = "0123456789ab"; + my $title = "commit title"; + my $tag_case = 1; + my $tag_space = 1; + my $id_length = 1; + my $id_case = 1; + my $title_has_quotes = 0; + + if ($line =~ /(\s*fixes:?)\s+([0-9a-f]{5,})\s+($balanced_parens)/i) { + my $tag = $1; + $orig_commit = $2; + $title = $3; + + $tag_case = 0 if $tag eq "Fixes:"; + $tag_space = 0 if ($line =~ /^fixes:? [0-9a-f]{5,} ($balanced_parens)/i); + + $id_length = 0 if ($orig_commit =~ /^[0-9a-f]{12}$/i); + $id_case = 0 if ($orig_commit !~ /[A-F]/); + + # Always strip leading/trailing parens then double quotes if existing + $title = substr($title, 1, -1); + if ($title =~ /^".*"$/) { + $title = substr($title, 1, -1); + $title_has_quotes = 1; + } + } + + my ($cid, $ctitle) = git_commit_info($orig_commit, $id, + $title); + + if ($ctitle ne $title || $tag_case || $tag_space || + $id_length || $id_case || !$title_has_quotes) { + if (WARN("BAD_FIXES_TAG", + "Please use correct Fixes: style 'Fixes: <12 chars of sha1> (\"\")' - ie: 'Fixes: $cid (\"$ctitle\")'\n" . $herecurr) && + $fix) { + $fixed[$fixlinenr] = "Fixes: $cid (\"$ctitle\")"; + } + } + } + # Check email subject for common tools that don't need to be mentioned if ($in_header_lines && $line =~ /^Subject:.*\b(?:checkpatch|sparse|smatch)\b[^:]/i) { -- cgit v1.2.3-59-g8ed1b From fc8c2d8ff20651f887e574767533d1176e3a479c Mon Sep 17 00:00:00 2001 From: Zack Rusin <zackr@vmware.com> Date: Thu, 6 Oct 2022 10:33:19 -0400 Subject: kbuild: Stop including vmlinux.bz2 in the rpm's vmlinux.bz2 was added to the rpm packages in 2009 in the fc370ecfdb37 ("kbuild: add vmlinux to kernel rpm") but seemingly hasn't been used since. Originally this should have been split up in a seperate debugging package because it massively increases the size of the generated rpm's e.g. kernel rpm built using binrpm-pkg on Fedora 36 default 5.19.8 kernel config and localmodconfig is ~255MB with vmlinux.bz2 and only ~65MB without it. Make the kernel built rpms about 4x smaller by not including the unused vmlinux.bz2 in them. Signed-off-by: Zack Rusin <zackr@vmware.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> --- scripts/package/mkspec | 2 -- 1 file changed, 2 deletions(-) (limited to 'scripts') diff --git a/scripts/package/mkspec b/scripts/package/mkspec index c920c1b18e7a..70392fd2fd29 100755 --- a/scripts/package/mkspec +++ b/scripts/package/mkspec @@ -97,8 +97,6 @@ $M $MAKE %{?_smp_mflags} INSTALL_MOD_PATH=%{buildroot} modules_install $MAKE %{?_smp_mflags} INSTALL_HDR_PATH=%{buildroot}/usr headers_install cp System.map %{buildroot}/boot/System.map-$KERNELRELEASE cp .config %{buildroot}/boot/config-$KERNELRELEASE - bzip2 -9 --keep vmlinux - mv vmlinux.bz2 %{buildroot}/boot/vmlinux-$KERNELRELEASE.bz2 $S$M rm -f %{buildroot}/lib/modules/$KERNELRELEASE/build $S$M rm -f %{buildroot}/lib/modules/$KERNELRELEASE/source $S$M mkdir -p %{buildroot}/usr/src/kernels/$KERNELRELEASE -- cgit v1.2.3-59-g8ed1b From 11df33c36c4b7a04d2674531f2c6178ad8d61572 Mon Sep 17 00:00:00 2001 From: Richard Acayan <mailingradian@gmail.com> Date: Mon, 10 Oct 2022 21:38:28 -0400 Subject: modpost: put modpost options before argument The musl implementation of getopt stops looking for options after the first non-option argument. Put the options before the non-option argument so environments using musl can still build the kernel and modules. Fixes: f73edc8951b2 ("kbuild: unify two modpost invocations") Link: https://git.musl-libc.org/cgit/musl/tree/src/misc/getopt.c?h=dc9285ad1dc19349c407072cc48ba70dab86de45#n44 Signed-off-by: Richard Acayan <mailingradian@gmail.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> --- scripts/Makefile.modpost | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index 7740ce3b29e8..8489a3402eb8 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -119,7 +119,7 @@ quiet_cmd_modpost = MODPOST $@ echo >&2 "WARNING: $(missing-input) is missing."; \ echo >&2 " Modules may not have dependencies or modversions."; \ echo >&2 " You may get many unresolved symbol warnings.";) \ - sed 's/ko$$/o/' $(or $(modorder-if-needed), /dev/null) | $(MODPOST) $(modpost-args) $(vmlinux.o-if-present) -T - + sed 's/ko$$/o/' $(or $(modorder-if-needed), /dev/null) | $(MODPOST) $(modpost-args) -T - $(vmlinux.o-if-present) targets += $(output-symdump) $(output-symdump): $(modorder-if-needed) $(vmlinux.o-if-present) $(moudle.symvers-if-present) $(MODPOST) FORCE -- cgit v1.2.3-59-g8ed1b From 04518e4c2edc78bc90b4651d50c4aad48d09ac23 Mon Sep 17 00:00:00 2001 From: Guru Das Srinagesh <quic_gurus@quicinc.com> Date: Tue, 11 Oct 2022 12:06:00 -0700 Subject: scripts/clang-tools: Convert clang-tidy args to list Convert list of clang-tidy arguments to a list for ease of adding to them and extending them as required. Signed-off-by: Guru Das Srinagesh <quic_gurus@quicinc.com> Suggested-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> --- scripts/clang-tools/run-clang-tools.py | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'scripts') diff --git a/scripts/clang-tools/run-clang-tools.py b/scripts/clang-tools/run-clang-tools.py index bb78c9bde55c..56f2ec8f0f40 100755 --- a/scripts/clang-tools/run-clang-tools.py +++ b/scripts/clang-tools/run-clang-tools.py @@ -45,13 +45,14 @@ def init(l, a): def run_analysis(entry): # Disable all checks, then re-enable the ones we want - checks = "-checks=-*," + checks = [] + checks.append("-checks=-*") if args.type == "clang-tidy": - checks += "linuxkernel-*" + checks.append("linuxkernel-*") else: - checks += "clang-analyzer-*" - checks += ",-clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling" - p = subprocess.run(["clang-tidy", "-p", args.path, checks, entry["file"]], + checks.append("clang-analyzer-*") + checks.append("-clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling") + p = subprocess.run(["clang-tidy", "-p", args.path, ",".join(checks), entry["file"]], stdout=subprocess.PIPE, stderr=subprocess.STDOUT, cwd=entry["directory"]) -- cgit v1.2.3-59-g8ed1b From c67a85bee78db74c6889a5ca645c3763ad23d863 Mon Sep 17 00:00:00 2001 From: Nick Desaulniers <ndesaulniers@google.com> Date: Fri, 14 Oct 2022 09:53:02 -0700 Subject: kbuild: add -fno-discard-value-names to cmd_cc_ll_c When debugging LLVM IR, it can be handy for clang to not discard value names used for local variables and parameters. Compare the generated IR. -fdiscard-value-names: define i32 @core_sys_select(i32 %0, ptr %1, ptr %2, ptr %3, ptr %4) { %6 = alloca i64 %7 = alloca %struct.poll_wqueues %8 = alloca [64 x i32] -fno-discard-value-names: define i32 @core_sys_select(i32 %n, ptr %inp, ptr %outp, ptr %exp, ptr %end_time) { %expire.i = alloca i64 %table.i = alloca %struct.poll_wqueues %stack_fds = alloca [64 x i32] The rule for generating human readable LLVM IR (.ll) is only useful as a debugging feature: $ make LLVM=1 fs/select.ll As Fangrui notes: A LLVM_ENABLE_ASSERTIONS=off build of Clang defaults to -fdiscard-value-names. A LLVM_ENABLE_ASSERTIONS=on build of Clang defaults to -fno-discard-value-names. Explicitly enable -fno-discard-value-names so that the IR always contains value names regardless of whether assertions were enabled or not. Assertions generally are not enabled in releases of clang packaged by distributions. Link: https://github.com/ClangBuiltLinux/linux/issues/1467 Reviewed-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Fangrui Song <maskray@google.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> --- scripts/Makefile.build | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 22adbf89cb31..41f3602fc8de 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -140,7 +140,7 @@ $(obj)/%.symtypes : $(src)/%.c FORCE # LLVM assembly # Generate .ll files from .c quiet_cmd_cc_ll_c = CC $(quiet_modtag) $@ - cmd_cc_ll_c = $(CC) $(c_flags) -emit-llvm -S -o $@ $< + cmd_cc_ll_c = $(CC) $(c_flags) -emit-llvm -S -fno-discard-value-names -o $@ $< $(obj)/%.ll: $(src)/%.c FORCE $(call if_changed_dep,cc_ll_c) -- cgit v1.2.3-59-g8ed1b