Messages in this thread Patch in this message | | | From | Xiaoyao Li <> | Subject | [PATCH] x86/cpufeatures: make bits in cpu_caps_cleared[] and cpu_cpus_set[] exclusive | Date | Wed, 18 Mar 2020 14:16:24 +0800 |
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In apply_forced_caps(), cpu_caps_set[] overrides cpu_caps_cleared[], so that setup_clear_cpu_cap() cannot clear one cap if setup_force_cpu_cap() sets the cap before it.
Explicitly clear the bit in cpu_caps_cleared[] when set it in cpu_caps_set[], and vice versa, can fix this.
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> --- arch/x86/include/asm/cpufeature.h | 1 + arch/x86/kernel/cpu/cpuid-deps.c | 1 + 2 files changed, 2 insertions(+)
diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index 59bf91c57aa8..f6d976b05d2c 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -144,6 +144,7 @@ extern void clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int bit); #define setup_force_cpu_cap(bit) do { \ set_cpu_cap(&boot_cpu_data, bit); \ set_bit(bit, (unsigned long *)cpu_caps_set); \ + clear_bit(bit, (unsigned long *)cpu_caps_cleared); \ } while (0) #define setup_force_cpu_bug(bit) setup_force_cpu_cap(bit) diff --git a/arch/x86/kernel/cpu/cpuid-deps.c b/arch/x86/kernel/cpu/cpuid-deps.c index 3cbe24ca80ab..e16c36094e6c 100644 --- a/arch/x86/kernel/cpu/cpuid-deps.c +++ b/arch/x86/kernel/cpu/cpuid-deps.c @@ -82,6 +82,7 @@ static inline void clear_feature(struct cpuinfo_x86 *c, unsigned int feature) if (!c) { clear_cpu_cap(&boot_cpu_data, feature); set_bit(feature, (unsigned long *)cpu_caps_cleared); + clear_bit(feature, (unsigned long *)cpu_caps_set); } else { clear_bit(feature, (unsigned long *)c->x86_capability); } -- 2.20.1
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