[PATCH 14/22] KVM: x86/mmu: Always walk guest PTEs with WRITE access when unprotecting

Sean Christopherson posted 22 patches 1 year, 6 months ago
There is a newer version of this series
[PATCH 14/22] KVM: x86/mmu: Always walk guest PTEs with WRITE access when unprotecting
Posted by Sean Christopherson 1 year, 6 months ago
When getting a gpa from a gva to unprotect the associated gfn when an
event is awating reinjection, walk the guest PTEs for WRITE as there's no
point in unprotecting the gfn if the guest is unable to write the page,
i.e. if write-protection can't trigger emulation.

Note, the entire flow should be guarded on the access being a write, and
even better should be conditioned on actually triggering a write-protect
fault.  This will be addressed in a future commit.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/mmu/mmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index a5d1f6232f8c..f64ad36ca9e0 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -2761,7 +2761,7 @@ static int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva)
 	if (vcpu->arch.mmu->root_role.direct)
 		return 0;
 
-	gpa = kvm_mmu_gva_to_gpa_read(vcpu, gva, NULL);
+	gpa = kvm_mmu_gva_to_gpa_write(vcpu, gva, NULL);
 	if (gpa == INVALID_GPA)
 		return 0;
 
-- 
2.46.0.76.ge559c4bf1a-goog