x86/fpu: Use _Alignof to avoid undefined behavior in TYPE_ALIGN
stable inclusion from stable-v5.10.165 commit 03ba86bb381114a4bbbcb4a700c1e9f085c336c9 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I7T7G4 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=03ba86bb381114a4bbbcb4a700c1e9f085c336c9 -------------------------------- commit 55228db2 upstream. WG14 N2350 specifies that it is an undefined behavior to have type definitions within offsetof", see https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2350.htm This specification is also part of C23. Therefore, replace the TYPE_ALIGN macro with the _Alignof builtin to avoid undefined behavior. (_Alignof itself is C11 and the kernel is built with -gnu11). ISO C11 _Alignof is subtly different from the GNU C extension __alignof__. Latter is the preferred alignment and _Alignof the minimal alignment. For long long on x86 these are 8 and 4 respectively. The macro TYPE_ALIGN's behavior matches _Alignof rather than __alignof__. [ bp: Massage commit message. ] Signed-off-by:YingChi Long <me@inclyc.cn> Signed-off-by:
Borislav Petkov <bp@suse.de> Reviewed-by:
Nick Desaulniers <ndesaulniers@google.com> Link: https://lore.kernel.org/r/20220925153151.2467884-1-me@inclyc.cn Signed-off-by:
Nathan Chancellor <nathan@kernel.org> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by:
sanglipeng <sanglipeng1@jd.com> Conflicts: arch/x86/kernel/fpu/init.c
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