linux-stable.git/include/linux/compiler_attributes.h, branch v5.15.208 Linux kernel stable tree locking: Introduce __cleanup() based infrastructure 2025-10-19T14:21:51+00:00 Peter Zijlstra peterz@infradead.org 2025-10-15T15:05:54+00:00 f550466949e822afcd0b546a4fc35795930660bc [ Upstream commit 54da6a0924311c7cf5015533991e44fb8eb12773 ] Use __attribute__((__cleanup__(func))) to build: - simple auto-release pointers using __free() - 'classes' with constructor and destructor semantics for scope-based resource management. - lock guards based on the above classes. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20230612093537.614161713%40infradead.org Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 54da6a0924311c7cf5015533991e44fb8eb12773 ]

Use __attribute__((__cleanup__(func))) to build:

 - simple auto-release pointers using __free()

 - 'classes' with constructor and destructor semantics for
   scope-based resource management.

 - lock guards based on the above classes.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230612093537.614161713%40infradead.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Compiler Attributes: Add __uninitialized macro 2024-07-18T11:07:26+00:00 Heiko Carstens hca@linux.ibm.com 2024-02-05T15:48:43+00:00 5e3070adafca2b648869310f34438f5d659a2c8e commit fd7eea27a3aed79b63b1726c00bde0d50cf207e2 upstream. With INIT_STACK_ALL_PATTERN or INIT_STACK_ALL_ZERO enabled the kernel will be compiled with -ftrivial-auto-var-init=<...> which causes initialization of stack variables at function entry time. In order to avoid the performance impact that comes with this users can use the "uninitialized" attribute to prevent such initialization. Therefore provide the __uninitialized macro which can be used for cases where INIT_STACK_ALL_PATTERN or INIT_STACK_ALL_ZERO is enabled, but only selected variables should not be initialized. Acked-by: Kees Cook <keescook@chromium.org> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20240205154844.3757121-2-hca@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit fd7eea27a3aed79b63b1726c00bde0d50cf207e2 upstream.

With INIT_STACK_ALL_PATTERN or INIT_STACK_ALL_ZERO enabled the kernel will
be compiled with -ftrivial-auto-var-init=<...> which causes initialization
of stack variables at function entry time.

In order to avoid the performance impact that comes with this users can use
the "uninitialized" attribute to prevent such initialization.

Therefore provide the __uninitialized macro which can be used for cases
where INIT_STACK_ALL_PATTERN or INIT_STACK_ALL_ZERO is enabled, but only
selected variables should not be initialized.

Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20240205154844.3757121-2-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Compiler Attributes: add __alloc_size() for better bounds checking 2022-07-12T14:35:01+00:00 Kees Cook keescook@chromium.org 2021-11-05T20:36:19+00:00 ff41804632e530e8f8971f45b23ca29d63edf243 [ Upstream commit 86cffecdeaa278444870c8745ab166a65865dbf0 ] GCC and Clang can use the "alloc_size" attribute to better inform the results of __builtin_object_size() (for compile-time constant values). Clang can additionally use alloc_size to inform the results of __builtin_dynamic_object_size() (for run-time values). Because GCC sees the frequent use of struct_size() as an allocator size argument, and notices it can return SIZE_MAX (the overflow indication), it complains about these call sites overflowing (since SIZE_MAX is greater than the default -Walloc-size-larger-than=PTRDIFF_MAX). This isn't helpful since we already know a SIZE_MAX will be caught at run-time (this was an intentional design). To deal with this, we must disable this check as it is both a false positive and redundant. (Clang does not have this warning option.) Unfortunately, just checking the -Wno-alloc-size-larger-than is not sufficient to make the __alloc_size attribute behave correctly under older GCC versions. The attribute itself must be disabled in those situations too, as there appears to be no way to reliably silence the SIZE_MAX constant expression cases for GCC versions less than 9.1: In file included from ./include/linux/resource_ext.h:11, from ./include/linux/pci.h:40, from drivers/net/ethernet/intel/ixgbe/ixgbe.h:9, from drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c:4: In function 'kmalloc_node', inlined from 'ixgbe_alloc_q_vector' at ./include/linux/slab.h:743:9: ./include/linux/slab.h:618:9: error: argument 1 value '18446744073709551615' exceeds maximum object size 9223372036854775807 [-Werror=alloc-size-larger-than=] return __kmalloc_node(size, flags, node); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ./include/linux/slab.h: In function 'ixgbe_alloc_q_vector': ./include/linux/slab.h:455:7: note: in a call to allocation function '__kmalloc_node' declared here void *__kmalloc_node(size_t size, gfp_t flags, int node) __assume_slab_alignment __malloc; ^~~~~~~~~~~~~~ Specifically: '-Wno-alloc-size-larger-than' is not correctly handled by GCC < 9.1 https://godbolt.org/z/hqsfG7q84 (doesn't disable) https://godbolt.org/z/P9jdrPTYh (doesn't admit to not knowing about option) https://godbolt.org/z/465TPMWKb (only warns when other warnings appear) '-Walloc-size-larger-than=18446744073709551615' is not handled by GCC < 8.2 https://godbolt.org/z/73hh1EPxz (ignores numeric value) Since anything marked with __alloc_size would also qualify for marking with __malloc, just include __malloc along with it to avoid redundant markings. (Suggested by Linus Torvalds.) Finally, make sure checkpatch.pl doesn't get confused about finding the __alloc_size attribute on functions. (Thanks to Joe Perches.) Link: https://lkml.kernel.org/r/20210930222704.2631604-3-keescook@chromium.org Signed-off-by: Kees Cook <keescook@chromium.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Cc: Andy Whitcroft <apw@canonical.com> Cc: Christoph Lameter <cl@linux.com> Cc: Daniel Micay <danielmicay@gmail.com> Cc: David Rientjes <rientjes@google.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Dwaipayan Ray <dwaipayanray1@gmail.com> Cc: Joe Perches <joe@perches.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Alexandre Bounine <alex.bou9@gmail.com> Cc: Gustavo A. R. Silva <gustavoars@kernel.org> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jing Xiangfeng <jingxiangfeng@huawei.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: kernel test robot <lkp@intel.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Souptick Joarder <jrdr.linux@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 86cffecdeaa278444870c8745ab166a65865dbf0 ]

GCC and Clang can use the "alloc_size" attribute to better inform the
results of __builtin_object_size() (for compile-time constant values).
Clang can additionally use alloc_size to inform the results of
__builtin_dynamic_object_size() (for run-time values).

Because GCC sees the frequent use of struct_size() as an allocator size
argument, and notices it can return SIZE_MAX (the overflow indication),
it complains about these call sites overflowing (since SIZE_MAX is
greater than the default -Walloc-size-larger-than=PTRDIFF_MAX).  This
isn't helpful since we already know a SIZE_MAX will be caught at
run-time (this was an intentional design).  To deal with this, we must
disable this check as it is both a false positive and redundant.  (Clang
does not have this warning option.)

Unfortunately, just checking the -Wno-alloc-size-larger-than is not
sufficient to make the __alloc_size attribute behave correctly under
older GCC versions.  The attribute itself must be disabled in those
situations too, as there appears to be no way to reliably silence the
SIZE_MAX constant expression cases for GCC versions less than 9.1:

   In file included from ./include/linux/resource_ext.h:11,
                    from ./include/linux/pci.h:40,
                    from drivers/net/ethernet/intel/ixgbe/ixgbe.h:9,
                    from drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c:4:
   In function 'kmalloc_node',
       inlined from 'ixgbe_alloc_q_vector' at ./include/linux/slab.h:743:9:
   ./include/linux/slab.h:618:9: error: argument 1 value '18446744073709551615' exceeds maximum object size 9223372036854775807 [-Werror=alloc-size-larger-than=]
     return __kmalloc_node(size, flags, node);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   ./include/linux/slab.h: In function 'ixgbe_alloc_q_vector':
   ./include/linux/slab.h:455:7: note: in a call to allocation function '__kmalloc_node' declared here
    void *__kmalloc_node(size_t size, gfp_t flags, int node) __assume_slab_alignment __malloc;
          ^~~~~~~~~~~~~~

Specifically:
 '-Wno-alloc-size-larger-than' is not correctly handled by GCC < 9.1
    https://godbolt.org/z/hqsfG7q84 (doesn't disable)
    https://godbolt.org/z/P9jdrPTYh (doesn't admit to not knowing about option)
    https://godbolt.org/z/465TPMWKb (only warns when other warnings appear)

 '-Walloc-size-larger-than=18446744073709551615' is not handled by GCC < 8.2
    https://godbolt.org/z/73hh1EPxz (ignores numeric value)

Since anything marked with __alloc_size would also qualify for marking
with __malloc, just include __malloc along with it to avoid redundant
markings.  (Suggested by Linus Torvalds.)

Finally, make sure checkpatch.pl doesn't get confused about finding the
__alloc_size attribute on functions.  (Thanks to Joe Perches.)

Link: https://lkml.kernel.org/r/20210930222704.2631604-3-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Daniel Micay <danielmicay@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexandre Bounine <alex.bou9@gmail.com>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jing Xiangfeng <jingxiangfeng@huawei.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Merge branch 'gcc-min-version-5.1' (make gcc-5.1 the minimum version) 2021-09-13T17:43:04+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-09-13T17:43:04+00:00 316346243be6df12799c0b64b788e06bad97c30b Merge patch series from Nick Desaulniers to update the minimum gcc version to 5.1. This is some of the left-overs from the merge window that I didn't want to deal with yesterday, so it comes in after -rc1 but was sent before. Gcc-4.9 support has been an annoyance for some time, and with -Werror I had the choice of applying a fairly big patch from Kees Cook to remove a fair number of initializer warnings (still leaving some), or this patch series from Nick that just removes the source of the problem. The initializer cleanups might still be worth it regardless, but honestly, I preferred just tackling the problem with gcc-4.9 head-on. We've been more aggressiuve about no longer having to care about compilers that were released a long time ago, and I think it's been a good thing. I added a couple of patches on top to sort out a few left-overs now that we no longer support gcc-4.x. As noted by Arnd, as a result of this minimum compiler version upgrade we can probably change our use of '--std=gnu89' to '--std=gnu11', and finally start using local loop declarations etc. But this series does _not_ yet do that. Link: https://lore.kernel.org/all/20210909182525.372ee687@canb.auug.org.au/ Link: https://lore.kernel.org/lkml/CAK7LNASs6dvU6D3jL2GG3jW58fXfaj6VNOe55NJnTB8UPuk2pA@mail.gmail.com/ Link: https://github.com/ClangBuiltLinux/linux/issues/1438 * emailed patches from Nick Desaulniers <ndesaulniers@google.com>: Drop some straggling mentions of gcc-4.9 as being stale compiler_attributes.h: drop __has_attribute() support for gcc4 vmlinux.lds.h: remove old check for GCC 4.9 compiler-gcc.h: drop checks for older GCC versions Makefile: drop GCC < 5 -fno-var-tracking-assignments workaround arm64: remove GCC version check for ARCH_SUPPORTS_INT128 powerpc: remove GCC version check for UPD_CONSTR riscv: remove Kconfig check for GCC version for ARCH_RV64I Kconfig.debug: drop GCC 5+ version check for DWARF5 mm/ksm: remove old GCC 4.9+ check compiler.h: drop fallback overflow checkers Documentation: raise minimum supported version of GCC to 5.1 
Merge patch series from Nick Desaulniers to update the minimum gcc
version to 5.1.

This is some of the left-overs from the merge window that I didn't want
to deal with yesterday, so it comes in after -rc1 but was sent before.

Gcc-4.9 support has been an annoyance for some time, and with -Werror I
had the choice of applying a fairly big patch from Kees Cook to remove a
fair number of initializer warnings (still leaving some), or this patch
series from Nick that just removes the source of the problem.

The initializer cleanups might still be worth it regardless, but
honestly, I preferred just tackling the problem with gcc-4.9 head-on.
We've been more aggressiuve about no longer having to care about
compilers that were released a long time ago, and I think it's been a
good thing.

I added a couple of patches on top to sort out a few left-overs now that
we no longer support gcc-4.x.

As noted by Arnd, as a result of this minimum compiler version upgrade
we can probably change our use of '--std=gnu89' to '--std=gnu11', and
finally start using local loop declarations etc.  But this series does
_not_ yet do that.

Link: https://lore.kernel.org/all/20210909182525.372ee687@canb.auug.org.au/
Link: https://lore.kernel.org/lkml/CAK7LNASs6dvU6D3jL2GG3jW58fXfaj6VNOe55NJnTB8UPuk2pA@mail.gmail.com/
Link: https://github.com/ClangBuiltLinux/linux/issues/1438

* emailed patches from Nick Desaulniers <ndesaulniers@google.com>:
  Drop some straggling mentions of gcc-4.9 as being stale
  compiler_attributes.h: drop __has_attribute() support for gcc4
  vmlinux.lds.h: remove old check for GCC 4.9
  compiler-gcc.h: drop checks for older GCC versions
  Makefile: drop GCC < 5 -fno-var-tracking-assignments workaround
  arm64: remove GCC version check for ARCH_SUPPORTS_INT128
  powerpc: remove GCC version check for UPD_CONSTR
  riscv: remove Kconfig check for GCC version for ARCH_RV64I
  Kconfig.debug: drop GCC 5+ version check for DWARF5
  mm/ksm: remove old GCC 4.9+ check
  compiler.h: drop fallback overflow checkers
  Documentation: raise minimum supported version of GCC to 5.1
Drop some straggling mentions of gcc-4.9 as being stale 2021-09-13T17:29:44+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-09-13T17:29:44+00:00 df26327ea097eb78e7967c45df6b23010c43c28d Fix up the admin-guide README file to the new gcc-5.1 requirement, and remove a stale comment about gcc support for the __assume_aligned__ attribute. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
Fix up the admin-guide README file to the new gcc-5.1 requirement, and
remove a stale comment about gcc support for the __assume_aligned__
attribute.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
compiler_attributes.h: drop __has_attribute() support for gcc4 2021-09-13T17:20:01+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-09-13T17:20:01+00:00 6d2ef226f2f18d530e48ead0cb5704505628b797 Now that GCC 5.1 is the minimally supported default, the manual workaround for older gcc versions not having __has_attribute() are no longer relevant and can be removed. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
Now that GCC 5.1 is the minimally supported default, the manual
workaround for older gcc versions not having __has_attribute() are no
longer relevant and can be removed.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge tag 'compiler-attributes-for-linus-v5.15-rc1-v2' of git://github.com/ojeda/linux 2021-09-12T23:09:26+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-09-12T23:09:26+00:00 c3e46874dfb9a2ef08085bb147dc371e72738673 Pull compiler attributes updates from Miguel Ojeda: - Fix __has_attribute(__no_sanitize_coverage__) for GCC 4 (Marco Elver) - Add Nick as Reviewer for compiler_attributes.h (Nick Desaulniers) - Move __compiletime_{error|warning} (Nick Desaulniers) * tag 'compiler-attributes-for-linus-v5.15-rc1-v2' of git://github.com/ojeda/linux: compiler_attributes.h: move __compiletime_{error|warning} MAINTAINERS: add Nick as Reviewer for compiler_attributes.h Compiler Attributes: fix __has_attribute(__no_sanitize_coverage__) for GCC 4 
Pull compiler attributes updates from Miguel Ojeda:

 - Fix __has_attribute(__no_sanitize_coverage__) for GCC 4 (Marco Elver)

 - Add Nick as Reviewer for compiler_attributes.h (Nick Desaulniers)

 - Move __compiletime_{error|warning} (Nick Desaulniers)

* tag 'compiler-attributes-for-linus-v5.15-rc1-v2' of git://github.com/ojeda/linux:
  compiler_attributes.h: move __compiletime_{error|warning}
  MAINTAINERS: add Nick as Reviewer for compiler_attributes.h
  Compiler Attributes: fix __has_attribute(__no_sanitize_coverage__) for GCC 4
compiler_attributes.h: move __compiletime_{error|warning} 2021-09-08T23:14:28+00:00 Nick Desaulniers ndesaulniers@google.com 2021-08-02T20:23:20+00:00 b83a908498d68fafca931e1276e145b339cac5fb Clang 14 will add support for __attribute__((__error__(""))) and __attribute__((__warning__(""))). To make use of these in __compiletime_error and __compiletime_warning (as used by BUILD_BUG and friends) for newer clang and detect/fallback for older versions of clang, move these to compiler_attributes.h and guard them with __has_attribute preprocessor guards. Link: https://reviews.llvm.org/D106030 Link: https://bugs.llvm.org/show_bug.cgi?id=16428 Link: https://github.com/ClangBuiltLinux/linux/issues/1173 Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> [Reworded, landed in Clang 14] Signed-off-by: Miguel Ojeda <ojeda@kernel.org> 
Clang 14 will add support for __attribute__((__error__(""))) and
__attribute__((__warning__(""))). To make use of these in
__compiletime_error and __compiletime_warning (as used by BUILD_BUG and
friends) for newer clang and detect/fallback for older versions of
clang, move these to compiler_attributes.h and guard them with
__has_attribute preprocessor guards.

Link: https://reviews.llvm.org/D106030
Link: https://bugs.llvm.org/show_bug.cgi?id=16428
Link: https://github.com/ClangBuiltLinux/linux/issues/1173
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
[Reworded, landed in Clang 14]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Compiler Attributes: fix __has_attribute(__no_sanitize_coverage__) for GCC 4 2021-07-15T23:06:44+00:00 Marco Elver elver@google.com 2021-07-14T15:01:59+00:00 7ed012969bbcdbd7aef5778a061681e6cbc4b402 Fix __has_attribute(__no_sanitize_coverage__) for GCC 4 by defining __GCC4_has_attribute___no_sanitize_coverage__. Fixes: 540540d06e9d ("kcov: add __no_sanitize_coverage to fix noinstr for all architectures") Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Miguel Ojeda <ojeda@kernel.org> 
Fix __has_attribute(__no_sanitize_coverage__) for GCC 4 by defining
__GCC4_has_attribute___no_sanitize_coverage__.

Fixes: 540540d06e9d ("kcov: add __no_sanitize_coverage to fix noinstr for all architectures")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Merge tag 'clang-features-v5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux 2021-06-30T21:33:25+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-06-30T21:33:25+00:00 44b6ed4cfab8474061707b60e35afaf2c92a9dc3 Pull clang feature updates from Kees Cook: - Add CC_HAS_NO_PROFILE_FN_ATTR in preparation for PGO support in the face of the noinstr attribute, paving the way for PGO and fixing GCOV. (Nick Desaulniers) - x86_64 LTO coverage is expanded to 32-bit x86. (Nathan Chancellor) - Small fixes to CFI. (Mark Rutland, Nathan Chancellor) * tag 'clang-features-v5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: qemu_fw_cfg: Make fw_cfg_rev_attr a proper kobj_attribute Kconfig: Introduce ARCH_WANTS_NO_INSTR and CC_HAS_NO_PROFILE_FN_ATTR compiler_attributes.h: cleanups for GCC 4.9+ compiler_attributes.h: define __no_profile, add to noinstr x86, lto: Enable Clang LTO for 32-bit as well CFI: Move function_nocfi() into compiler.h MAINTAINERS: Add Clang CFI section 
Pull clang feature updates from Kees Cook:

 - Add CC_HAS_NO_PROFILE_FN_ATTR in preparation for PGO support in the
   face of the noinstr attribute, paving the way for PGO and fixing
   GCOV. (Nick Desaulniers)

 - x86_64 LTO coverage is expanded to 32-bit x86. (Nathan Chancellor)

 - Small fixes to CFI. (Mark Rutland, Nathan Chancellor)

* tag 'clang-features-v5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  qemu_fw_cfg: Make fw_cfg_rev_attr a proper kobj_attribute
  Kconfig: Introduce ARCH_WANTS_NO_INSTR and CC_HAS_NO_PROFILE_FN_ATTR
  compiler_attributes.h: cleanups for GCC 4.9+
  compiler_attributes.h: define __no_profile, add to noinstr
  x86, lto: Enable Clang LTO for 32-bit as well
  CFI: Move function_nocfi() into compiler.h
  MAINTAINERS: Add Clang CFI section