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authorDave Hansen <dave.hansen@linux.intel.com>2016-06-29 13:01:08 -0700
committerIngo Molnar <mingo@kernel.org>2016-06-30 09:11:32 +0200
commit1e61f78baf893c7eb49f633d23ccbb420c8f808e (patch)
tree9cbf7d3472606f50a517cc2e82bc36541d2a9ea8 /arch/x86/include/asm/required-features.h
parent6e17cb9c2d5efd8fcc3934e983733302b9912ff8 (diff)
downloadlinux-0-day-1e61f78baf893c7eb49f633d23ccbb420c8f808e.tar.gz
linux-0-day-1e61f78baf893c7eb49f633d23ccbb420c8f808e.tar.xz
x86/cpufeature: Make sure DISABLED/REQUIRED macros are updated
x86 has two macros which allow us to evaluate some CPUID-based features at compile time: REQUIRED_MASK_BIT_SET() DISABLED_MASK_BIT_SET() They're both defined by having the compiler check the bit argument against some constant masks of features. But, when adding new CPUID leaves, we need to check new words for these macros. So make sure that those macros and the REQUIRED_MASK* and DISABLED_MASK* get updated when necessary. This looks kinda silly to have an open-coded value ("18" in this case) open-coded in 5 places in the code. But, we really do need 5 places updated when NCAPINTS gets bumped, so now we just force the issue. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160629200108.92466F6F@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/include/asm/required-features.h')
-rw-r--r--arch/x86/include/asm/required-features.h1
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/include/asm/required-features.h b/arch/x86/include/asm/required-features.h
index fad4277d582e9..fac9a5c0abe94 100644
--- a/arch/x86/include/asm/required-features.h
+++ b/arch/x86/include/asm/required-features.h
@@ -100,5 +100,6 @@
#define REQUIRED_MASK15 0
#define REQUIRED_MASK16 0
#define REQUIRED_MASK17 0
+#define REQUIRED_MASK_CHECK BUILD_BUG_ON_ZERO(NCAPINTS != 18)
#endif /* _ASM_X86_REQUIRED_FEATURES_H */