From 46505c0f69f99cc8cf0b50842a35a49200db5144 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Wed, 27 Nov 2024 17:33:53 -0800 Subject: [PATCH] KVM: x86: Handle kernel- and KVM-defined CPUID words in a single helper Merge kvm_cpu_cap_init() and kvm_cpu_cap_init_kvm_defined() into a single helper. The only advantage of separating the two was to make it somewhat obvious that KVM directly initializes the KVM-defined words, whereas using a common helper will allow for hardening both kernel- and KVM-defined CPUID words without needing copy+paste. No functional change intended. Link: https://lore.kernel.org/r/20241128013424.4096668-27-seanjc@google.com Signed-off-by: Sean Christopherson --- arch/x86/kvm/cpuid.c | 46 +++++++++++++++----------------------------- 1 file changed, 16 insertions(+), 30 deletions(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 11cd176a26f8f..2cd06155684ef 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -623,37 +623,23 @@ static __always_inline u32 raw_cpuid_get(struct cpuid_reg cpuid) return *__cpuid_entry_get_reg(&entry, cpuid.reg); } -/* Mask kvm_cpu_caps for @leaf with the raw CPUID capabilities of this CPU. */ -static __always_inline void __kvm_cpu_cap_mask(unsigned int leaf) +static __always_inline void kvm_cpu_cap_init(u32 leaf, u32 mask) { const struct cpuid_reg cpuid = x86_feature_cpuid(leaf * 32); - reverse_cpuid_check(leaf); + /* + * For kernel-defined leafs, mask the boot CPU's pre-populated value. + * For KVM-defined leafs, explicitly set the leaf, as KVM is the one + * and only authority. + */ + if (leaf < NCAPINTS) + kvm_cpu_caps[leaf] &= mask; + else + kvm_cpu_caps[leaf] = mask; kvm_cpu_caps[leaf] &= raw_cpuid_get(cpuid); } -static __always_inline -void kvm_cpu_cap_init_kvm_defined(enum kvm_only_cpuid_leafs leaf, u32 mask) -{ - /* Use kvm_cpu_cap_init for leafs that aren't KVM-only. */ - BUILD_BUG_ON(leaf < NCAPINTS); - - kvm_cpu_caps[leaf] = mask; - - __kvm_cpu_cap_mask(leaf); -} - -static __always_inline void kvm_cpu_cap_init(enum cpuid_leafs leaf, u32 mask) -{ - /* Use kvm_cpu_cap_init_kvm_defined for KVM-only leafs. */ - BUILD_BUG_ON(leaf >= NCAPINTS); - - kvm_cpu_caps[leaf] &= mask; - - __kvm_cpu_cap_mask(leaf); -} - #define F feature_bit /* Scattered Flag - For features that are scattered by cpufeatures.h. */ @@ -864,7 +850,7 @@ void kvm_set_cpu_caps(void) F(LAM) ); - kvm_cpu_cap_init_kvm_defined(CPUID_7_1_EDX, + kvm_cpu_cap_init(CPUID_7_1_EDX, F(AVX_VNNI_INT8) | F(AVX_NE_CONVERT) | F(AMX_COMPLEX) | @@ -873,7 +859,7 @@ void kvm_set_cpu_caps(void) F(AVX10) ); - kvm_cpu_cap_init_kvm_defined(CPUID_7_2_EDX, + kvm_cpu_cap_init(CPUID_7_2_EDX, F(INTEL_PSFD) | F(IPRED_CTRL) | F(RRSBA_CTRL) | @@ -890,13 +876,13 @@ void kvm_set_cpu_caps(void) X86_64_F(XFD) ); - kvm_cpu_cap_init_kvm_defined(CPUID_12_EAX, + kvm_cpu_cap_init(CPUID_12_EAX, SF(SGX1) | SF(SGX2) | SF(SGX_EDECCSSA) ); - kvm_cpu_cap_init_kvm_defined(CPUID_24_0_EBX, + kvm_cpu_cap_init(CPUID_24_0_EBX, F(AVX10_128) | F(AVX10_256) | F(AVX10_512) @@ -959,7 +945,7 @@ void kvm_set_cpu_caps(void) if (!tdp_enabled && IS_ENABLED(CONFIG_X86_64)) kvm_cpu_cap_set(X86_FEATURE_GBPAGES); - kvm_cpu_cap_init_kvm_defined(CPUID_8000_0007_EDX, + kvm_cpu_cap_init(CPUID_8000_0007_EDX, SF(CONSTANT_TSC) ); @@ -1033,7 +1019,7 @@ void kvm_set_cpu_caps(void) kvm_cpu_cap_check_and_set(X86_FEATURE_IBPB_BRTYPE); kvm_cpu_cap_check_and_set(X86_FEATURE_SRSO_NO); - kvm_cpu_cap_init_kvm_defined(CPUID_8000_0022_EAX, + kvm_cpu_cap_init(CPUID_8000_0022_EAX, F(PERFMON_V2) ); -- 2.47.2