linux-dev/Makefile, branch linus/master

Linux 5.19-rc3

2022-06-19T20:06:47Z

Linux 5.19-rc2

2022-06-12T23:11:37Z

gcc-12: disable '-Warray-bounds' universally for now

2022-06-09T17:11:12Z

In commit 8b202ee21839 ("s390: disable -Warray-bounds") the s390 people disabled the '-Warray-bounds' warning for gcc-12, because the new logic in gcc would cause warnings for their use of the S390_lowcore macro, which accesses absolute pointers. It turns out gcc-12 has many other issues in this area, so this takes that s390 warning disable logic, and turns it into a kernel build config entry instead. Part of the intent is that we can make this all much more targeted, and use this conflig flag to disable it in only particular configurations that cause problems, with the s390 case as an example: select GCC12_NO_ARRAY_BOUNDS and we could do that for other configuration cases that cause issues. Or we could possibly use the CONFIG_CC_NO_ARRAY_BOUNDS thing in a more targeted way, and disable the warning only for particular uses: again the s390 case as an example: KBUILD_CFLAGS_DECOMPRESSOR += $(if $(CONFIG_CC_NO_ARRAY_BOUNDS),-Wno-array-bounds) but this ends up just doing it globally in the top-level Makefile, since the current issues are spread fairly widely all over: KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds We'll try to limit this later, since the gcc-12 problems are rare enough that *much* of the kernel can be built with it without disabling this warning. Cc: Kees Cook Cc: Nathan Chancellor Signed-off-by: Linus Torvalds

gcc-12: disable '-Wdangling-pointer' warning for now

2022-06-09T16:41:42Z

While the concept of checking for dangling pointers to local variables at function exit is really interesting, the gcc-12 implementation is not compatible with reality, and results in false positives. For example, gcc sees us putting things on a local list head allocated on the stack, which involves exactly those kinds of pointers to the local stack entry: In function ‘__list_add’, inlined from ‘list_add_tail’ at include/linux/list.h:102:2, inlined from ‘rebuild_snap_realms’ at fs/ceph/snap.c:434:2: include/linux/list.h:74:19: warning: storing the address of local variable ‘realm_queue’ in ‘*&realm_27(D)->rebuild_item.prev’ [-Wdangling-pointer=] 74 | new->prev = prev; | ~~~~~~~~~~^~~~~~ But then gcc - understandably - doesn't really understand the big picture how the doubly linked list works, so doesn't see how we then end up emptying said list head in a loop and the pointer we added has been removed. Gcc also complains about us (intentionally) using this as a way to store a kind of fake stack trace, eg drivers/acpi/acpica/utdebug.c:40:38: warning: storing the address of local variable ‘current_sp’ in ‘acpi_gbl_entry_stack_pointer’ [-Wdangling-pointer=] 40 | acpi_gbl_entry_stack_pointer = ¤t_sp; | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~ which is entirely reasonable from a compiler standpoint, and we may want to change those kinds of patterns, but not not. So this is one of those "it would be lovely if the compiler were to complain about us leaving dangling pointers to the stack", but not this way. Signed-off-by: Linus Torvalds

Linux 5.19-rc1

2022-06-06T00:18:54Z

kbuild: clean .tmp_* pattern by make clean

2022-06-04T21:20:57Z

Change the "make clean" rule to remove all the .tmp_* files. .tmp_objdiff is the only exception, which should be removed by "make mrproper". Rename the record directory of objdiff, .tmp_objdiff to .objdiff to avoid the removal by "make clean". Signed-off-by: Masahiro Yamada Tested-by: Sedat Dilek # LLVM-14 (x86-64)

Merge tag 'kbuild-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2022-05-26T19:09:50Z

Pull Kbuild updates from Masahiro Yamada: - Add HOSTPKG_CONFIG env variable to allow users to override pkg-config - Support W=e as a shorthand for KCFLAGS=-Werror - Fix CONFIG_IKHEADERS build to support toybox cpio - Add scripts/dummy-tools/pahole to ease distro packagers' life - Suppress false-positive warnings from checksyscalls.sh for W=2 build - Factor out the common code of arch/*/boot/install.sh into scripts/install.sh - Support 'kernel-install' tool in scripts/prune-kernel - Refactor module-versioning to link the symbol versions at the final link of vmlinux and modules - Remove CONFIG_MODULE_REL_CRCS because module-versioning now works in an arch-agnostic way - Refactor modpost, Makefiles * tag 'kbuild-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (56 commits) genksyms: adjust the output format to modpost kbuild: stop merging *.symversions kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS modpost: extract symbol versions from *.cmd files modpost: add sym_find_with_module() helper modpost: change the license of EXPORT_SYMBOL to bool type modpost: remove left-over cross_compile declaration kbuild: record symbol versions in *.cmd files kbuild: generate a list of objects in vmlinux modpost: move *.mod.c generation to write_mod_c_files() modpost: merge add_{intree_flag,retpoline,staging_flag} to add_header scripts/prune-kernel: Use kernel-install if available kbuild: factor out the common installation code into scripts/install.sh modpost: split new_symbol() to symbol allocation and hash table addition modpost: make sym_add_exported() always allocate a new symbol modpost: make multiple export error modpost: dump Module.symvers in the same order of modules.order modpost: traverse the namespace_list in order modpost: use doubly linked list for dump_lists modpost: traverse unresolved symbols in order ...

Merge tag 'kernel-hardening-v5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

2022-05-24T19:27:09Z

Pull kernel hardening updates from Kees Cook: - usercopy hardening expanded to check other allocation types (Matthew Wilcox, Yuanzheng Song) - arm64 stackleak behavioral improvements (Mark Rutland) - arm64 CFI code gen improvement (Sami Tolvanen) - LoadPin LSM block dev API adjustment (Christoph Hellwig) - Clang randstruct support (Bill Wendling, Kees Cook) * tag 'kernel-hardening-v5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (34 commits) loadpin: stop using bdevname mm: usercopy: move the virt_addr_valid() below the is_vmalloc_addr() gcc-plugins: randstruct: Remove cast exception handling af_unix: Silence randstruct GCC plugin warning niu: Silence randstruct warnings big_keys: Use struct for internal payload gcc-plugins: Change all version strings match kernel randomize_kstack: Improve docs on requirements/rationale lkdtm/stackleak: fix CONFIG_GCC_PLUGIN_STACKLEAK=n arm64: entry: use stackleak_erase_on_task_stack() stackleak: add on/off stack variants lkdtm/stackleak: check stack boundaries lkdtm/stackleak: prevent unexpected stack usage lkdtm/stackleak: rework boundary management lkdtm/stackleak: avoid spurious failure stackleak: rework poison scanning stackleak: rework stack high bound handling stackleak: clarify variable names stackleak: rework stack low bound handling stackleak: remove redundant check ...

Merge tag 'objtool-core-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2022-05-24T17:36:38Z

Pull objtool updates from Ingo Molnar: - Comprehensive interface overhaul: ================================= Objtool's interface has some issues: - Several features are done unconditionally, without any way to turn them off. Some of them might be surprising. This makes objtool tricky to use, and prevents porting individual features to other arches. - The config dependencies are too coarse-grained. Objtool enablement is tied to CONFIG_STACK_VALIDATION, but it has several other features independent of that. - The objtool subcmds ("check" and "orc") are clumsy: "check" is really a subset of "orc", so it has all the same options. The subcmd model has never really worked for objtool, as it only has a single purpose: "do some combination of things on an object file". - The '--lto' and '--vmlinux' options are nonsensical and have surprising behavior. Overhaul the interface: - get rid of subcmds - make all features individually selectable - remove and/or clarify confusing/obsolete options - update the documentation - fix some bugs found along the way - Fix x32 regression - Fix Kbuild cleanup bugs - Add scripts/objdump-func helper script to disassemble a single function from an object file. - Rewrite scripts/faddr2line to be section-aware, by basing it on 'readelf', moving it away from 'nm', which doesn't handle multiple sections well, which can result in decoding failure. - Rewrite & fix symbol handling - which had a number of bugs wrt. object files that don't have global symbols - which is rare but possible. Also fix a bunch of symbol handling bugs found along the way. * tag 'objtool-core-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) objtool: Fix objtool regression on x32 systems objtool: Fix symbol creation scripts/faddr2line: Fix overlapping text section failures scripts: Create objdump-func helper script objtool: Remove libsubcmd.a when make clean objtool: Remove inat-tables.c when make clean objtool: Update documentation objtool: Remove --lto and --vmlinux in favor of --link objtool: Add HAVE_NOINSTR_VALIDATION objtool: Rename "VMLINUX_VALIDATION" -> "NOINSTR_VALIDATION" objtool: Make noinstr hacks optional objtool: Make jump label hack optional objtool: Make static call annotation optional objtool: Make stack validation frame-pointer-specific objtool: Add CONFIG_OBJTOOL objtool: Extricate sls from stack validation objtool: Rework ibt and extricate from stack validation objtool: Make stack validation optional objtool: Add option to print section addresses objtool: Don't print parentheses in function addresses ...

Linux 5.18

2022-05-22T19:52:31Z