diff options
author | Marco Elver <elver@google.com> | 2019-07-12 06:53:56 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-07-12 21:05:42 +0300 |
commit | ff66135015726696568e998720d9b6afe2d04642 (patch) | |
tree | 1fc944414fb159898871708993a1f0744e84cdb9 /arch/x86/kernel | |
parent | 19a33ca6c209f5e22c73b6beb4b1974153e93050 (diff) | |
download | linux-ff66135015726696568e998720d9b6afe2d04642.tar.xz |
x86: use static_cpu_has in uaccess region to avoid instrumentation
This patch is a pre-requisite for enabling KASAN bitops instrumentation;
using static_cpu_has instead of boot_cpu_has avoids instrumentation of
test_bit inside the uaccess region. With instrumentation, the KASAN
check would otherwise be flagged by objtool.
For consistency, kernel/signal.c was changed to mirror this change,
however, is never instrumented with KASAN (currently unsupported under
x86 32bit).
Link: http://lkml.kernel.org/r/20190613125950.197667-3-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Suggested-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r-- | arch/x86/kernel/signal.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index 7cf508f78c8c..8eb7193e158d 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -391,7 +391,7 @@ static int __setup_rt_frame(int sig, struct ksignal *ksig, put_user_ex(&frame->uc, &frame->puc); /* Create the ucontext. */ - if (boot_cpu_has(X86_FEATURE_XSAVE)) + if (static_cpu_has(X86_FEATURE_XSAVE)) put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); else put_user_ex(0, &frame->uc.uc_flags); |