From: Ke Guo <guoke@xxxxxxxxxxxxx> Use kvm_pat_valid() directly instead of bouncing through kvm_mtrr_valid(). The PAT is not an MTRR, and kvm_mtrr_valid() just redirects to kvm_pat_valid(), i.e. is exempt from KVM's "zap SPTEs" logic that's needed to honor guest MTRRs when the VM has a passthrough device with non-coherent DMA (KVM does NOT set "ignore guest PAT" in this case, and so enables hardware virtualization of the guest's PAT, i.e. doesn't need to manually emulate the PAT memtype). Signed-off-by: Ke Guo <guoke@xxxxxxxxxxxxx> [sean: massage changelog] Reviewed-by: Kai Huang <kai.huang@xxxxxxxxx> Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx> --- arch/x86/kvm/svm/svm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index eb308c9994f9..db237ccdc957 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -2935,7 +2935,7 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr) break; case MSR_IA32_CR_PAT: - if (!kvm_mtrr_valid(vcpu, MSR_IA32_CR_PAT, data)) + if (!kvm_pat_valid(data)) return 1; vcpu->arch.pat = data; svm->vmcb01.ptr->save.g_pat = data; -- 2.40.1.606.ga4b1b128d6-goog