[PATCH 2/3] x86/cpu: Elide KCSAN for cpu_has() and friends

From: Peter Zijlstra
Date: Mon May 02 2022 - 07:13:03 EST


vmlinux.o: warning: objtool: enter_from_user_mode+0x24: call to __kcsan_check_access() leaves .noinstr.text section
vmlinux.o: warning: objtool: syscall_enter_from_user_mode+0x28: call to __kcsan_check_access() leaves .noinstr.text section
vmlinux.o: warning: objtool: syscall_enter_from_user_mode_prepare+0x24: call to __kcsan_check_access() leaves .noinstr.text section
vmlinux.o: warning: objtool: irqentry_enter_from_user_mode+0x24: call to __kcsan_check_access() leaves .noinstr.text section

Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
arch/x86/include/asm/cpufeature.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -51,7 +51,7 @@ extern const char * const x86_power_flag
extern const char * const x86_bug_flags[NBUGINTS*32];

#define test_cpu_cap(c, bit) \
- test_bit(bit, (unsigned long *)((c)->x86_capability))
+ arch_test_bit(bit, (unsigned long *)((c)->x86_capability))

/*
* There are 32 bits/features in each mask word. The high bits