The following commit has been merged into the x86/cpu branch of tip: Commit-ID: b7059f21b1c1c4ca5966d16bd3d9fa45cee89a87 Gitweb: https://git.kernel.org/tip/b7059f21b1c1c4ca5966d16bd3d9fa45cee89a87 Author: Kim Phillips <kim.phillips@xxxxxxx> AuthorDate: Mon, 16 Jan 2023 17:01:57 -06:00 Committer: Borislav Petkov (AMD) <bp@xxxxxxxxx> CommitterDate: Tue, 17 Jan 2023 13:00:12 +01:00 x86/cpu, kvm: Add the SMM_CTL MSR not present feature The SMM_CTL MSR not present feature was being open-coded for KVM in __do_cpuid_func(). Add it to its newly added CPUID leaf 0x80000021 EAX proper, and propagate it in kvm_set_cpu_caps() instead. Also drop the bit description comments now the code is more self-describing, and retain the SmmPgCfgLock and PrefetchCtlMsr feature bit comments at the kvm_cpu_cap_mask() callsite. Signed-off-by: Kim Phillips <kim.phillips@xxxxxxx> Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx> Link: https://lore.kernel.org/r/20230116230159.1511393-6-kim.phillips@xxxxxxx --- arch/x86/include/asm/cpufeatures.h | 1 + arch/x86/kvm/cpuid.c | 13 +++---------- 2 files changed, 4 insertions(+), 10 deletions(-) diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h index 6bed80c..86e98bd 100644 --- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.h @@ -431,6 +431,7 @@ #define X86_FEATURE_NO_NESTED_DATA_BP (20*32+ 0) /* "" No Nested Data Breakpoints */ #define X86_FEATURE_LFENCE_RDTSC (20*32+ 2) /* "" LFENCE always serializing / synchronizes RDTSC */ #define X86_FEATURE_NULL_SEL_CLR_BASE (20*32+ 6) /* "" Null Selector Clears Base */ +#define X86_FEATURE_NO_SMM_CTL_MSR (20*32+ 9) /* "" SMM_CTL MSR is not present */ /* * BUG word(s) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 04f2f48..56f00d9 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -742,12 +742,14 @@ void kvm_set_cpu_caps(void) F(SME_COHERENT)); kvm_cpu_cap_mask(CPUID_8000_0021_EAX, - F(NO_NESTED_DATA_BP) | F(LFENCE_RDTSC) | F(NULL_SEL_CLR_BASE) + F(NO_NESTED_DATA_BP) | F(LFENCE_RDTSC) | 0 /* SmmPgCfgLock */ | + F(NULL_SEL_CLR_BASE) | 0 /* PrefetchCtlMsr */ ); if (cpu_feature_enabled(X86_FEATURE_LFENCE_RDTSC)) kvm_cpu_cap_set(X86_FEATURE_LFENCE_RDTSC); if (!static_cpu_has_bug(X86_BUG_NULL_SEG)) kvm_cpu_cap_set(X86_FEATURE_NULL_SEL_CLR_BASE); + kvm_cpu_cap_set(X86_FEATURE_NO_SMM_CTL_MSR); kvm_cpu_cap_mask(CPUID_C000_0001_EDX, F(XSTORE) | F(XSTORE_EN) | F(XCRYPT) | F(XCRYPT_EN) | @@ -1231,15 +1233,6 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) case 0x80000021: entry->ebx = entry->ecx = entry->edx = 0; cpuid_entry_override(entry, CPUID_8000_0021_EAX); - /* - * Other defined bits are for MSRs that KVM does not expose: - * EAX 3 SPCL, SMM page configuration lock - * EAX 13 PCMSR, Prefetch control MSR - * - * KVM doesn't support SMM_CTL. - * EAX 9 SMM_CTL MSR is not supported - */ - entry->eax |= BIT(9); break; /*Add support for Centaur's CPUID instruction*/ case 0xC0000000:
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