Introduce a helper to quickly check if KVM needs to handle VMCALL/VMMCALL from L2 in L0 to process Direct TLB flush requests. Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/hyperv.c | 6 ++++++ arch/x86/kvm/hyperv.h | 7 +++++++ 3 files changed, 14 insertions(+) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 45ee05f4f1a0..bcaf05951628 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -611,6 +611,7 @@ struct kvm_vcpu_hv { u32 enlightenments_eax; /* HYPERV_CPUID_ENLIGHTMENT_INFO.EAX */ u32 enlightenments_ebx; /* HYPERV_CPUID_ENLIGHTMENT_INFO.EBX */ u32 syndbg_cap_eax; /* HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES.EAX */ + u32 nested_features_eax; /* HYPERV_CPUID_NESTED_FEATURES.EAX */ } cpuid_cache; /* Two rings for regular Hyper-V TLB flush and Direct TLB flush */ diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index 865b4d9a26fe..31acc08a6b23 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -2270,6 +2270,12 @@ void kvm_hv_set_cpuid(struct kvm_vcpu *vcpu) hv_vcpu->cpuid_cache.syndbg_cap_eax = entry->eax; else hv_vcpu->cpuid_cache.syndbg_cap_eax = 0; + + entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_NESTED_FEATURES, 0); + if (entry) + hv_vcpu->cpuid_cache.nested_features_eax = entry->eax; + else + hv_vcpu->cpuid_cache.nested_features_eax = 0; } int kvm_hv_set_enforce_cpuid(struct kvm_vcpu *vcpu, bool enforce) diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h index 0c0877a6aa74..0c9062aed182 100644 --- a/arch/x86/kvm/hyperv.h +++ b/arch/x86/kvm/hyperv.h @@ -169,6 +169,13 @@ static inline void kvm_hv_vcpu_empty_flush_tlb(struct kvm_vcpu *vcpu) tlb_flush_ring->read_idx = tlb_flush_ring->write_idx; } +static inline bool kvm_hv_direct_tlb_flush_exposed(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu); + + return hv_vcpu && (hv_vcpu->cpuid_cache.nested_features_eax & HV_X64_NESTED_DIRECT_FLUSH); +} + static inline bool kvm_hv_is_tlb_flush_hcall(struct kvm_vcpu *vcpu) { struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu); -- 2.35.1