diff options
| author | Sean Christopherson <seanjc@google.com> | 2021-02-22 05:45:21 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-02-22 21:13:30 +0300 |
| commit | 5f8a7cf25a7da5c2bbde25b3f0aca31459d20741 (patch) | |
| tree | 9fecd14d3a0057cbc81d5b04b9738e9bb95a519f | |
| parent | 356c7558d453338c9184809c0926071dfbfb9c80 (diff) | |
| download | linux-5f8a7cf25a7da5c2bbde25b3f0aca31459d20741.tar.xz | |
KVM: x86/mmu: Skip mmu_notifier check when handling MMIO page fault
Don't retry a page fault due to an mmu_notifier invalidation when
handling a page fault for a GPA that did not resolve to a memslot, i.e.
an MMIO page fault. Invalidations from the mmu_notifier signal a change
in a host virtual address (HVA) mapping; without a memslot, there is no
HVA and thus no possibility that the invalidation is relevant to the
page fault being handled.
Note, the MMIO vs. memslot generation checks handle the case where a
pending memslot will create a memslot overlapping the faulting GPA. The
mmu_notifier checks are orthogonal to memslot updates.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210222024522.1751719-2-stevensd@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/mmu/mmu.c | 2 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/paging_tmpl.h | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 6e78d8e51aa2..752b4b7ab01b 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -3712,7 +3712,7 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code, else write_lock(&vcpu->kvm->mmu_lock); - if (mmu_notifier_retry(vcpu->kvm, mmu_seq)) + if (!is_noslot_pfn(pfn) && mmu_notifier_retry(vcpu->kvm, mmu_seq)) goto out_unlock; r = make_mmu_pages_available(vcpu); if (r) diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h index d9f66cc459e8..5844d3979bb8 100644 --- a/arch/x86/kvm/mmu/paging_tmpl.h +++ b/arch/x86/kvm/mmu/paging_tmpl.h @@ -869,7 +869,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gpa_t addr, u32 error_code, r = RET_PF_RETRY; write_lock(&vcpu->kvm->mmu_lock); - if (mmu_notifier_retry(vcpu->kvm, mmu_seq)) + if (!is_noslot_pfn(pfn) && mmu_notifier_retry(vcpu->kvm, mmu_seq)) goto out_unlock; kvm_mmu_audit(vcpu, AUDIT_PRE_PAGE_FAULT); |