From c10398b6d0ddb9c8234890828ab83341e11f9840 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Mon, 2 Mar 2020 15:56:46 -0800 Subject: KVM: x86: Use KVM cpu caps to mark CR4.LA57 as not-reserved Add accessor(s) for KVM cpu caps and use said accessor to detect hardware support for LA57 instead of manually querying CPUID. Note, the explicit conversion to bool via '!!' in kvm_cpu_cap_has() is technically unnecessary, but it gives people a warm fuzzy feeling. No functional change intended. Reviewed-by: Vitaly Kuznetsov Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini --- arch/x86/kvm/cpuid.h | 13 +++++++++++++ arch/x86/kvm/x86.c | 2 +- 2 files changed, 14 insertions(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h index fd29b646916a..e3dc0f02ad5c 100644 --- a/arch/x86/kvm/cpuid.h +++ b/arch/x86/kvm/cpuid.h @@ -282,6 +282,19 @@ static __always_inline void kvm_cpu_cap_set(unsigned int x86_feature) kvm_cpu_caps[x86_leaf] |= __feature_bit(x86_feature); } +static __always_inline u32 kvm_cpu_cap_get(unsigned int x86_feature) +{ + unsigned int x86_leaf = x86_feature / 32; + + reverse_cpuid_check(x86_leaf); + return kvm_cpu_caps[x86_leaf] & __feature_bit(x86_feature); +} + +static __always_inline bool kvm_cpu_cap_has(unsigned int x86_feature) +{ + return !!kvm_cpu_cap_get(x86_feature); +} + static __always_inline void kvm_cpu_cap_check_and_set(unsigned int x86_feature) { if (boot_cpu_has(x86_feature)) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 849957f3afb2..389bc80f684c 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -925,7 +925,7 @@ static u64 kvm_host_cr4_reserved_bits(struct cpuinfo_x86 *c) { u64 reserved_bits = __cr4_reserved_bits(cpu_has, c); - if (cpuid_ecx(0x7) & feature_bit(LA57)) + if (kvm_cpu_cap_has(X86_FEATURE_LA57)) reserved_bits &= ~X86_CR4_LA57; if (kvm_x86_ops->umip_emulated()) -- cgit v1.2.3