diff options
Diffstat (limited to 'arch/x86/kvm/vmx.c')
| -rw-r--r-- | arch/x86/kvm/vmx.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 59b080c262e..e8a5649f9c1 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -3581,11 +3581,26 @@ static u64 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) { u64 ret; + /* For VT-d and EPT combination + * 1. MMIO: always map as UC + * 2. EPT with VT-d: + * a. VT-d without snooping control feature: can't guarantee the + * result, try to trust guest. + * b. VT-d with snooping control feature: snooping control feature of + * VT-d engine can guarantee the cache correctness. Just set it + * to WB to keep consistent with host. So the same as item 3. + * 3. EPT without VT-d: always map as WB and set IGMT=1 to keep + * consistent with host MTRR + */ if (is_mmio) ret = MTRR_TYPE_UNCACHABLE << VMX_EPT_MT_EPTE_SHIFT; + else if (vcpu->kvm->arch.iommu_domain && + !(vcpu->kvm->arch.iommu_flags & KVM_IOMMU_CACHE_COHERENCY)) + ret = kvm_get_guest_memory_type(vcpu, gfn) << + VMX_EPT_MT_EPTE_SHIFT; else - ret = (kvm_get_guest_memory_type(vcpu, gfn) << - VMX_EPT_MT_EPTE_SHIFT) | VMX_EPT_IGMT_BIT; + ret = (MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT) + | VMX_EPT_IGMT_BIT; return ret; } |