We shouldn't probably be suggesting using Enlightened VMCS when it's not enabled (not supported from guest's point of view). System reset through synthetic MSR is not recommended neither by genuine Hyper-V nor my QEMU. Windows seems to be fine either way but let's be consistent. Fixes: 2bc39970e932 ("x86/kvm/hyper-v: Introduce KVM_GET_SUPPORTED_HV_CPUID") Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> --- arch/x86/kvm/hyperv.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index ac44a681f065..4730fcaa70cf 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -1847,11 +1847,11 @@ int kvm_vcpu_ioctl_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid, case HYPERV_CPUID_ENLIGHTMENT_INFO: ent->eax |= HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED; ent->eax |= HV_X64_APIC_ACCESS_RECOMMENDED; - ent->eax |= HV_X64_SYSTEM_RESET_RECOMMENDED; ent->eax |= HV_X64_RELAXED_TIMING_RECOMMENDED; ent->eax |= HV_X64_CLUSTER_IPI_RECOMMENDED; ent->eax |= HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED; - ent->eax |= HV_X64_ENLIGHTENED_VMCS_RECOMMENDED; + if (evmcs_ver) + ent->eax |= HV_X64_ENLIGHTENED_VMCS_RECOMMENDED; /* * Default number of spinlock retry attempts, matches -- 2.20.1