diff options
| -rw-r--r-- | arch/x86/kvm/mmu/mmu.c | 19 |
1 files changed, 12 insertions, 7 deletions
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index f36e3cdde25d..add486220dae 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -3044,16 +3044,14 @@ static bool handle_abnormal_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fa static bool page_fault_can_be_fast(struct kvm_page_fault *fault) { /* - * Do not fix the mmio spte with invalid generation number which - * need to be updated by slow page fault path. + * Page faults with reserved bits set, i.e. faults on MMIO SPTEs, only + * reach the common page fault handler if the SPTE has an invalid MMIO + * generation number. Refreshing the MMIO generation needs to go down + * the slow path. Note, EPT Misconfigs do NOT set the PRESENT flag! */ if (fault->rsvd) return false; - /* See if the page fault is due to an NX violation */ - if (unlikely(fault->exec && fault->present)) - return false; - /* * #PF can be fast if: * @@ -3069,7 +3067,14 @@ static bool page_fault_can_be_fast(struct kvm_page_fault *fault) * SPTE is MMU-writable (determined later), the fault can be fixed * by setting the Writable bit, which can be done out of mmu_lock. */ - return !kvm_ad_enabled() || (fault->write && fault->present); + if (!fault->present) + return !kvm_ad_enabled(); + + /* + * Note, instruction fetches and writes are mutually exclusive, ignore + * the "exec" flag. + */ + return fault->write; } /* |