[PATCH RFC 06/22] KVM: x86: hyper-v: Honor HV_MSR_VP_INDEX_AVAILABLE privilege bit
From: Vitaly Kuznetsov <vkuznets@redhat.com>
Date: 2021-04-13 12:27:30
Also in:
kvm, lkml
Subsystem:
kernel virtual machine for x86 (kvm/x86), kvm x86 hyper-v (kvm/hyper-v), the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Sean Christopherson, Paolo Bonzini, Vitaly Kuznetsov, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
HV_X64_MSR_VP_INDEX is only available to guest when HV_MSR_VP_INDEX_AVAILABLE bit is exposed. Note, writing to HV_X64_MSR_VP_INDEX is only available from the host so kvm_hv_set_msr() doesn't need an additional check. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> --- arch/x86/kvm/hyperv.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 7fdd9b9c50d6..07f1fc8575e5 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c@@ -1514,6 +1514,10 @@ static int kvm_hv_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, switch (msr) { case HV_X64_MSR_VP_INDEX: + if (unlikely(!host && !(hv_vcpu->cpuid_cache.features_eax & + HV_MSR_VP_INDEX_AVAILABLE))) + return 1; + data = hv_vcpu->vp_index; break; case HV_X64_MSR_EOI:
--
2.30.2