1 files changed, 35 insertions, 10 deletions

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c3ee5e29ea2a..edff19d1df97 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4462,6 +4462,21 @@ out:
 }
 EXPORT_SYMBOL_GPL(kvm_write_guest_virt_system);
 
+static int vcpu_is_mmio_gpa(struct kvm_vcpu *vcpu, unsigned long gva,
+			    gpa_t gpa, bool write)
+{
+	/* For APIC access vmexit */
+	if ((gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)
+		return 1;
+
+	if (vcpu_match_mmio_gpa(vcpu, gpa)) {
+		trace_vcpu_match_mmio(gva, gpa, write, true);
+		return 1;
+	}
+
+	return 0;
+}
+
 static int vcpu_mmio_gva_to_gpa(struct kvm_vcpu *vcpu, unsigned long gva,
 				gpa_t *gpa, struct x86_exception *exception,
 				bool write)
@@ -4488,16 +4503,7 @@ static int vcpu_mmio_gva_to_gpa(struct kvm_vcpu *vcpu, unsigned long gva,
 	if (*gpa == UNMAPPED_GVA)
 		return -1;
 
-	/* For APIC access vmexit */
-	if ((*gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)
-		return 1;
-
-	if (vcpu_match_mmio_gpa(vcpu, *gpa)) {
-		trace_vcpu_match_mmio(gva, *gpa, write, true);
-		return 1;
-	}
-
-	return 0;
+	return vcpu_is_mmio_gpa(vcpu, gva, *gpa, write);
 }
 
 int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa,
@@ -4594,6 +4600,22 @@ static int emulator_read_write_onepage(unsigned long addr, void *val,
 	int handled, ret;
 	bool write = ops->write;
 	struct kvm_mmio_fragment *frag;
+	struct x86_emulate_ctxt *ctxt = &vcpu->arch.emulate_ctxt;
+
+	/*
+	 * If the exit was due to a NPF we may already have a GPA.
+	 * If the GPA is present, use it to avoid the GVA to GPA table walk.
+	 * Note, this cannot be used on string operations since string
+	 * operation using rep will only have the initial GPA from the NPF
+	 * occurred.
+	 */
+	if (vcpu->arch.gpa_available &&
+	    emulator_can_use_gpa(ctxt) &&
+	    vcpu_is_mmio_gpa(vcpu, addr, exception->address, write) &&
+	    (addr & ~PAGE_MASK) == (exception->address & ~PAGE_MASK)) {
+		gpa = exception->address;
+		goto mmio;
+	}
 
 	ret = vcpu_mmio_gva_to_gpa(vcpu, addr, &gpa, exception, write);
 
@@ -5610,6 +5632,9 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu,
 	}
 
 restart:
+	/* Save the faulting GPA (cr2) in the address field */
+	ctxt->exception.address = cr2;
+
 	r = x86_emulate_insn(ctxt);
 
 	if (r == EMULATION_INTERCEPTED)