From a5dc8300df75e8b8384b4c82225f1e4a0b4d9b55 Mon Sep 17 00:00:00 2001 From: Sasha Levin Date: Mon, 15 Jun 2020 18:24:27 -0400 Subject: scripts/decode_stacktrace: warn when modpath is needed but is unset When a user tries to parse a symbol located inside a module he must have modpath set. Otherwise, decode_stacktrace won't be able to parse the symbol correctly. Right now the failure is silent and easily missed by the user. What's worse is that by the time the user realizes what happened (or someone on LKML asks him to add the modpath and re-run), he might have already got rid of the vmlinux/modules. Signed-off-by: Sasha Levin Signed-off-by: Linus Torvalds --- scripts/decode_stacktrace.sh | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/decode_stacktrace.sh b/scripts/decode_stacktrace.sh index 13e5fbafdf2f..66a6d511b524 100755 --- a/scripts/decode_stacktrace.sh +++ b/scripts/decode_stacktrace.sh @@ -27,7 +27,10 @@ parse_symbol() { elif [[ "${modcache[$module]+isset}" == "isset" ]]; then local objfile=${modcache[$module]} else - [[ $modpath == "" ]] && return + if [[ $modpath == "" ]]; then + echo "WARNING! Modules path isn't set, but is needed to parse this symbol" >&2 + return + fi local objfile=$(find "$modpath" -name "${module//_/[-_]}.ko*" -print -quit) [[ $objfile == "" ]] && return modcache[$module]=$objfile -- cgit v1.3-8-gc7d7 From f2f02ebd8f3833626642688b2d2c6a7b3c141fa9 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 14 Jun 2020 23:43:40 +0900 Subject: kbuild: improve cc-option to clean up all temporary files When cc-option and friends evaluate compiler flags, the temporary file $$TMP is created as an output object, and automatically cleaned up. The actual file path of $$TMP is ..tmp, here is the process ID of $(shell ...) invoked from cc-option. (Please note $$$$ is the escape sequence of $$). Such garbage files are cleaned up in most cases, but some compiler flags create additional output files. For example, -gsplit-dwarf creates a .dwo file. When CONFIG_DEBUG_INFO_SPLIT=y, you will see a bunch of ..dwo files left in the top of build directories. You may not notice them unless you do 'ls -a', but the garbage files will increase every time you run 'make'. This commit changes the temporary object path to .tmp_/tmp, and removes .tmp_ directory when exiting. Separate build artifacts such as *.dwo will be cleaned up all together because their file paths are usually determined based on the base name of the object. Another example is -ftest-coverage, which outputs the coverage data into .gcno Signed-off-by: Masahiro Yamada --- scripts/Kbuild.include | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'scripts') diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index 0c3dc983439b..9a15fbf66aa1 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -86,20 +86,21 @@ cc-cross-prefix = $(firstword $(foreach c, $(1), \ $(if $(shell command -v -- $(c)gcc 2>/dev/null), $(c)))) # output directory for tests below -TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/) +TMPOUT = $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_$$$$ # try-run # Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise) # Exit code chooses option. "$$TMP" serves as a temporary file and is # automatically cleaned up. try-run = $(shell set -e; \ - TMP="$(TMPOUT).$$$$.tmp"; \ - TMPO="$(TMPOUT).$$$$.o"; \ + TMP=$(TMPOUT)/tmp; \ + TMPO=$(TMPOUT)/tmp.o; \ + mkdir -p $(TMPOUT); \ + trap "rm -rf $(TMPOUT)" EXIT; \ if ($(1)) >/dev/null 2>&1; \ then echo "$(2)"; \ else echo "$(3)"; \ - fi; \ - rm -f "$$TMP" "$$TMPO") + fi) # as-option # Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,) -- cgit v1.3-8-gc7d7 From 4ef57b21d6fb49d2b25c47e4cff467a0c2c8b6b7 Mon Sep 17 00:00:00 2001 From: Sami Tolvanen Date: Fri, 24 Apr 2020 12:30:46 -0700 Subject: recordmcount: support >64k sections When compiling a kernel with Clang and LTO, we need to run recordmcount on vmlinux.o with a large number of sections, which currently fails as the program doesn't understand extended section indexes. This change adds support for processing binaries with >64k sections. Link: https://lkml.kernel.org/r/20200424193046.160744-1-samitolvanen@google.com Link: https://lore.kernel.org/lkml/CAK7LNARbZhoaA=Nnuw0=gBrkuKbr_4Ng_Ei57uafujZf7Xazgw@mail.gmail.com/ Cc: Kees Cook Reviewed-by: Matt Helsley Signed-off-by: Sami Tolvanen Signed-off-by: Steven Rostedt (VMware) --- scripts/recordmcount.h | 98 ++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 92 insertions(+), 6 deletions(-) (limited to 'scripts') diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h index 74eab03e31d4..f9b19524da11 100644 --- a/scripts/recordmcount.h +++ b/scripts/recordmcount.h @@ -29,6 +29,11 @@ #undef has_rel_mcount #undef tot_relsize #undef get_mcountsym +#undef find_symtab +#undef get_shnum +#undef set_shnum +#undef get_shstrndx +#undef get_symindex #undef get_sym_str_and_relp #undef do_func #undef Elf_Addr @@ -58,6 +63,11 @@ # define __has_rel_mcount __has64_rel_mcount # define has_rel_mcount has64_rel_mcount # define tot_relsize tot64_relsize +# define find_symtab find_symtab64 +# define get_shnum get_shnum64 +# define set_shnum set_shnum64 +# define get_shstrndx get_shstrndx64 +# define get_symindex get_symindex64 # define get_sym_str_and_relp get_sym_str_and_relp_64 # define do_func do64 # define get_mcountsym get_mcountsym_64 @@ -91,6 +101,11 @@ # define __has_rel_mcount __has32_rel_mcount # define has_rel_mcount has32_rel_mcount # define tot_relsize tot32_relsize +# define find_symtab find_symtab32 +# define get_shnum get_shnum32 +# define set_shnum set_shnum32 +# define get_shstrndx get_shstrndx32 +# define get_symindex get_symindex32 # define get_sym_str_and_relp get_sym_str_and_relp_32 # define do_func do32 # define get_mcountsym get_mcountsym_32 @@ -173,6 +188,67 @@ static int MIPS_is_fake_mcount(Elf_Rel const *rp) return is_fake; } +static unsigned int get_symindex(Elf_Sym const *sym, Elf32_Word const *symtab, + Elf32_Word const *symtab_shndx) +{ + unsigned long offset; + int index; + + if (sym->st_shndx != SHN_XINDEX) + return w2(sym->st_shndx); + + offset = (unsigned long)sym - (unsigned long)symtab; + index = offset / sizeof(*sym); + + return w(symtab_shndx[index]); +} + +static unsigned int get_shnum(Elf_Ehdr const *ehdr, Elf_Shdr const *shdr0) +{ + if (shdr0 && !ehdr->e_shnum) + return w(shdr0->sh_size); + + return w2(ehdr->e_shnum); +} + +static void set_shnum(Elf_Ehdr *ehdr, Elf_Shdr *shdr0, unsigned int new_shnum) +{ + if (new_shnum >= SHN_LORESERVE) { + ehdr->e_shnum = 0; + shdr0->sh_size = w(new_shnum); + } else + ehdr->e_shnum = w2(new_shnum); +} + +static int get_shstrndx(Elf_Ehdr const *ehdr, Elf_Shdr const *shdr0) +{ + if (ehdr->e_shstrndx != SHN_XINDEX) + return w2(ehdr->e_shstrndx); + + return w(shdr0->sh_link); +} + +static void find_symtab(Elf_Ehdr *const ehdr, Elf_Shdr const *shdr0, + unsigned const nhdr, Elf32_Word **symtab, + Elf32_Word **symtab_shndx) +{ + Elf_Shdr const *relhdr; + unsigned k; + + *symtab = NULL; + *symtab_shndx = NULL; + + for (relhdr = shdr0, k = nhdr; k; --k, ++relhdr) { + if (relhdr->sh_type == SHT_SYMTAB) + *symtab = (void *)ehdr + relhdr->sh_offset; + else if (relhdr->sh_type == SHT_SYMTAB_SHNDX) + *symtab_shndx = (void *)ehdr + relhdr->sh_offset; + + if (*symtab && *symtab_shndx) + break; + } +} + /* Append the new shstrtab, Elf_Shdr[], __mcount_loc and its relocations. */ static int append_func(Elf_Ehdr *const ehdr, Elf_Shdr *const shstr, @@ -188,10 +264,12 @@ static int append_func(Elf_Ehdr *const ehdr, char const *mc_name = (sizeof(Elf_Rela) == rel_entsize) ? ".rela__mcount_loc" : ".rel__mcount_loc"; - unsigned const old_shnum = w2(ehdr->e_shnum); uint_t const old_shoff = _w(ehdr->e_shoff); uint_t const old_shstr_sh_size = _w(shstr->sh_size); uint_t const old_shstr_sh_offset = _w(shstr->sh_offset); + Elf_Shdr *const shdr0 = (Elf_Shdr *)(old_shoff + (void *)ehdr); + unsigned int const old_shnum = get_shnum(ehdr, shdr0); + unsigned int const new_shnum = 2 + old_shnum; /* {.rel,}__mcount_loc */ uint_t t = 1 + strlen(mc_name) + _w(shstr->sh_size); uint_t new_e_shoff; @@ -201,6 +279,8 @@ static int append_func(Elf_Ehdr *const ehdr, t += (_align & -t); /* word-byte align */ new_e_shoff = t; + set_shnum(ehdr, shdr0, new_shnum); + /* body for new shstrtab */ if (ulseek(sb.st_size, SEEK_SET) < 0) return -1; @@ -255,7 +335,6 @@ static int append_func(Elf_Ehdr *const ehdr, return -1; ehdr->e_shoff = _w(new_e_shoff); - ehdr->e_shnum = w2(2 + w2(ehdr->e_shnum)); /* {.rel,}__mcount_loc */ if (ulseek(0, SEEK_SET) < 0) return -1; if (uwrite(ehdr, sizeof(*ehdr)) < 0) @@ -434,6 +513,8 @@ static int find_secsym_ndx(unsigned const txtndx, uint_t *const recvalp, unsigned int *sym_index, Elf_Shdr const *const symhdr, + Elf32_Word const *symtab, + Elf32_Word const *symtab_shndx, Elf_Ehdr const *const ehdr) { Elf_Sym const *const sym0 = (Elf_Sym const *)(_w(symhdr->sh_offset) @@ -445,7 +526,7 @@ static int find_secsym_ndx(unsigned const txtndx, for (symp = sym0, t = nsym; t; --t, ++symp) { unsigned int const st_bind = ELF_ST_BIND(symp->st_info); - if (txtndx == w2(symp->st_shndx) + if (txtndx == get_symindex(symp, symtab, symtab_shndx) /* avoid STB_WEAK */ && (STB_LOCAL == st_bind || STB_GLOBAL == st_bind)) { /* function symbols on ARM have quirks, avoid them */ @@ -516,21 +597,23 @@ static unsigned tot_relsize(Elf_Shdr const *const shdr0, return totrelsz; } - /* Overall supervision for Elf32 ET_REL file. */ static int do_func(Elf_Ehdr *const ehdr, char const *const fname, unsigned const reltype) { Elf_Shdr *const shdr0 = (Elf_Shdr *)(_w(ehdr->e_shoff) + (void *)ehdr); - unsigned const nhdr = w2(ehdr->e_shnum); - Elf_Shdr *const shstr = &shdr0[w2(ehdr->e_shstrndx)]; + unsigned const nhdr = get_shnum(ehdr, shdr0); + Elf_Shdr *const shstr = &shdr0[get_shstrndx(ehdr, shdr0)]; char const *const shstrtab = (char const *)(_w(shstr->sh_offset) + (void *)ehdr); Elf_Shdr const *relhdr; unsigned k; + Elf32_Word *symtab; + Elf32_Word *symtab_shndx; + /* Upper bound on space: assume all relevant relocs are for mcount. */ unsigned totrelsz; @@ -561,6 +644,8 @@ static int do_func(Elf_Ehdr *const ehdr, char const *const fname, return -1; } + find_symtab(ehdr, shdr0, nhdr, &symtab, &symtab_shndx); + for (relhdr = shdr0, k = nhdr; k; --k, ++relhdr) { char const *const txtname = has_rel_mcount(relhdr, shdr0, shstrtab, fname); @@ -577,6 +662,7 @@ static int do_func(Elf_Ehdr *const ehdr, char const *const fname, result = find_secsym_ndx(w(relhdr->sh_info), txtname, &recval, &recsym, &shdr0[symsec_sh_link], + symtab, symtab_shndx, ehdr); if (result) goto out; -- cgit v1.3-8-gc7d7 From 4d0831e8a029c03f49f434f28b8faef9f0bd403f Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 14 Jun 2020 23:43:41 +0900 Subject: kconfig: unify cc-option and as-option cc-option and as-option are almost the same; both pass the flag to $(CC). The main difference is the cc-option stops before the assemble stage (-S option) whereas as-option stops after (-c option). I chose -S because it is slightly faster, but $(cc-option,-gz=zlib) returns a wrong result (https://lkml.org/lkml/2020/6/9/1529). It has been fixed by commit 7b16994437c7 ("Makefile: Improve compressed debug info support detection"), but the assembler should always be invoked for more reliable compiler option tests. However, you cannot simply replace -S with -c because the following code in lib/Kconfig.debug would break: depends on $(cc-option,-gsplit-dwarf) The combination of -c and -gsplit-dwarf does not accept /dev/null as output. $ cat /dev/null | gcc -gsplit-dwarf -S -x c - -o /dev/null $ echo $? 0 $ cat /dev/null | gcc -gsplit-dwarf -c -x c - -o /dev/null objcopy: Warning: '/dev/null' is not an ordinary file $ echo $? 1 $ cat /dev/null | gcc -gsplit-dwarf -c -x c - -o tmp.o $ echo $? 0 There is another flag that creates an separate file based on the object file path: $ cat /dev/null | gcc -ftest-coverage -c -x c - -o /dev/null :1: error: cannot open /dev/null.gcno So, we cannot use /dev/null to sink the output. Align the cc-option implementation with scripts/Kbuild.include. With -c option used in cc-option, as-option is unneeded. Signed-off-by: Masahiro Yamada Acked-by: Will Deacon --- arch/arm64/Kconfig | 2 +- lib/Kconfig.debug | 1 - scripts/Kconfig.include | 8 +------- 3 files changed, 2 insertions(+), 9 deletions(-) (limited to 'scripts') diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 31380da53689..6eb18f45258e 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1564,7 +1564,7 @@ config CC_HAS_SIGN_RETURN_ADDRESS def_bool $(cc-option,-msign-return-address=all) config AS_HAS_PAC - def_bool $(as-option,-Wa$(comma)-march=armv8.3-a) + def_bool $(cc-option,-Wa$(comma)-march=armv8.3-a) config AS_HAS_CFI_NEGATE_RA_STATE def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n) diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 96999d4d2dda..9ad9210d70a1 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -229,7 +229,6 @@ config DEBUG_INFO_COMPRESSED bool "Compressed debugging information" depends on DEBUG_INFO depends on $(cc-option,-gz=zlib) - depends on $(as-option,-gz=zlib) depends on $(ld-option,--compress-debug-sections=zlib) help Compress the debug information using zlib. Requires GCC 5.0+ or Clang diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include index c264da2b9b30..a5fe72c504ff 100644 --- a/scripts/Kconfig.include +++ b/scripts/Kconfig.include @@ -25,18 +25,12 @@ failure = $(if-success,$(1),n,y) # $(cc-option,) # Return y if the compiler supports , n otherwise -cc-option = $(success,$(CC) -Werror $(CLANG_FLAGS) $(1) -S -x c /dev/null -o /dev/null) +cc-option = $(success,mkdir .tmp_$$$$; trap "rm -rf .tmp_$$$$" EXIT; $(CC) -Werror $(CLANG_FLAGS) $(1) -c -x c /dev/null -o .tmp_$$$$/tmp.o) # $(ld-option,) # Return y if the linker supports , n otherwise ld-option = $(success,$(LD) -v $(1)) -# $(as-option,) -# /dev/zero is used as output instead of /dev/null as some assembler cribs when -# both input and output are same. Also both of them have same write behaviour so -# can be easily substituted. -as-option = $(success, $(CC) $(CLANG_FLAGS) $(1) -c -x assembler /dev/null -o /dev/zero) - # $(as-instr,) # Return y if the assembler supports , n otherwise as-instr = $(success,printf "%b\n" "$(1)" | $(CC) $(CLANG_FLAGS) -c -x assembler -o /dev/null -) -- cgit v1.3-8-gc7d7 From 0f50d21ade110e519425a5c1e2cfee7a130d1a0e Mon Sep 17 00:00:00 2001 From: Masanari Iida Date: Tue, 16 Jun 2020 21:51:32 +0900 Subject: scripts: Fix typo in headers_install.sh This patch fixes a spelling typo in scripts/headers_install.sh Signed-off-by: Masanari Iida Signed-off-by: Masahiro Yamada --- scripts/headers_install.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/headers_install.sh b/scripts/headers_install.sh index 955cf3aedf21..224f51012b6e 100755 --- a/scripts/headers_install.sh +++ b/scripts/headers_install.sh @@ -11,7 +11,7 @@ then echo "asm/inline/volatile keywords." echo echo "INFILE: header file to operate on" - echo "OUTFILE: output file which the processed header is writen to" + echo "OUTFILE: output file which the processed header is written to" exit 1 fi -- cgit v1.3-8-gc7d7