From a1116fd67a3178ce220ee6c2c8abe6bf792e26f2 Mon Sep 17 00:00:00 2001 From: Kim Phillips Date: Tue, 24 Jan 2023 10:33:14 -0600 Subject: [PATCH 31/36] x86/cpu, kvm: Add the NO_NESTED_DATA_BP feature The "Processor ignores nested data breakpoints" feature was being open-coded for KVM. Add the feature to its newly introduced CPUID leaf 0x80000021 EAX proper. Signed-off-by: Kim Phillips Signed-off-by: Borislav Petkov (AMD) Acked-by: Sean Christopherson Link: https://lore.kernel.org/r/20230124163319.2277355-4-kim.phillips@amd.com (cherry picked from commit a9dc9ec5a1fafc3d2fe7a7b594eefaeaccf89a6b) Signed-off-by: Mridula Shastry Reviewed-by: Todd Vierling --- arch/x86/include/asm/cpufeatures.h | 3 +++ arch/x86/kvm/cpuid.c | 2 +- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h index ffc806d3a863..ac6e58a79fad 100644 --- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.h @@ -421,6 +421,9 @@ #define X86_FEATURE_IBRS_EXIT_SET (22*32+ 0) /* "" Set IBRS on kernel exit */ #define X86_FEATURE_IBRS_EXIT_SKIP (22*32+ 1) /* "" Skip SPEC_CTRL MSR write on exit */ +/* AMD-defined Extended Feature 2 EAX, CPUID level 0x80000021 (EAX), word 20 */ +#define X86_FEATURE_NO_NESTED_DATA_BP (20*32+ 0) /* "" No Nested Data Breakpoints */ + /* * BUG word(s) */ diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 2ca5ac683c44..1a8dbad7e2d9 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -683,7 +683,7 @@ void kvm_set_cpu_caps(void) F(SME_COHERENT)); kvm_cpu_cap_mask(CPUID_8000_0021_EAX, - BIT(0) /* NO_NESTED_DATA_BP */ | + F(NO_NESTED_DATA_BP) | BIT(2) /* LFENCE Always serializing */ | 0 /* SmmPgCfgLock */ | BIT(6) /* NULL_SEL_CLR_BASE */ | 0 /* PrefetchCtlMsr */ ); -- 2.39.3