From: Borislav Petkov <[email protected]> We add another 32-bit vector at the end of the ->x86_capability bitvector which collects bugs present in CPUs. After all, a CPU bug is a kind of a capability, albeit a strange one.
Signed-off-by: Borislav Petkov <[email protected]> --- arch/x86/include/asm/cpufeature.h | 34 ++++++++++++++++++++++++++++++++++ arch/x86/include/asm/processor.h | 2 +- arch/x86/kernel/alternative.c | 2 +- arch/x86/kernel/cpu/common.c | 4 ++++ 4 files changed, 40 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index 2d9075e863a0..68daf877dad5 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -9,6 +9,7 @@ #endif #define NCAPINTS 10 /* N 32-bit words worth of info */ +#define NBUGINTS 1 /* N 32-bit bug flags */ /* * Note: If the comment begins with a quoted string, that string is used @@ -399,6 +400,39 @@ static __always_inline __pure bool __static_cpu_has(u16 bit) #define static_cpu_has(bit) boot_cpu_has(bit) #endif +#define __BUG_CHECK_BIT(bit) \ +({ \ + WARN_ON(bit >> 5 < NCAPINTS); \ + bit; \ +}) + +#define cpu_has_bug(c, bit) \ +({ \ + unsigned __bit = __BUG_CHECK_BIT((bit)); \ + cpu_has(c, __bit); \ +}) + +#define boot_cpu_has_bug(bit) \ + cpu_has_bug(&boot_cpu_data, (bit)) + +#define static_cpu_has_bug(bit) \ +({ \ + unsigned __bit = __BUG_CHECK_BIT((bit)); \ + static_cpu_has(__bit); \ +}) + +#define set_cpu_bug(c, bit) \ +({ \ + unsigned __bit = __BUG_CHECK_BIT((bit)); \ + set_cpu_cap(c, __bit); \ +}) + +#define clear_cpu_bug(c, bit) \ +({ \ + unsigned __bit = __BUG_CHECK_BIT((bit)); \ + clear_cpu_cap(c, __bit); \ +}) + #endif /* defined(__KERNEL__) && !defined(__ASSEMBLY__) */ #endif /* _ASM_X86_CPUFEATURE_H */ diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 439f27a41ee8..67721c634bf0 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -108,7 +108,7 @@ struct cpuinfo_x86 { __u32 extended_cpuid_level; /* Maximum supported CPUID level, -1=no CPUID: */ int cpuid_level; - __u32 x86_capability[NCAPINTS]; + __u32 x86_capability[NCAPINTS + NBUGINTS]; char x86_vendor_id[16]; char x86_model_id[64]; /* in KB - valid for CPUS which support this call: */ diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index ef5ccca79a6c..c15cf9a25e27 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -271,7 +271,7 @@ void __init_or_module apply_alternatives(struct alt_instr *start, replacement = (u8 *)&a->repl_offset + a->repl_offset; BUG_ON(a->replacementlen > a->instrlen); BUG_ON(a->instrlen > sizeof(insnbuf)); - BUG_ON(a->cpuid >= NCAPINTS*32); + BUG_ON(a->cpuid >= (NCAPINTS + NBUGINTS) * 32); if (!boot_cpu_has(a->cpuid)) continue; diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index d814772c5bed..22018f70a671 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -920,6 +920,10 @@ static void __cpuinit identify_cpu(struct cpuinfo_x86 *c) /* AND the already accumulated flags with these */ for (i = 0; i < NCAPINTS; i++) boot_cpu_data.x86_capability[i] &= c->x86_capability[i]; + + /* OR, i.e. replicate the bug flags */ + for (i = NCAPINTS; i < NCAPINTS + NBUGINTS; i++) + c->x86_capability[i] |= boot_cpu_data.x86_capability[i]; } /* Init Machine Check Exception if available. */ -- 1.8.1.3.535.ga923c31 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
