kvm: vmx: Use the hardware provided GPA instead of page walk

As in the SVM patch, the guest physical address is passed by
VMX to x86_emulate_instruction already, so mark the GPA as available
in vcpu->arch.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 6a441a9..3d63919 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -6381,6 +6381,7 @@
 			EPT_VIOLATION_EXECUTABLE))
 		      ? PFERR_PRESENT_MASK : 0;
 
+	vcpu->arch.gpa_available = true;
 	vcpu->arch.exit_qualification = exit_qualification;
 
 	return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0);
@@ -6398,6 +6399,7 @@
 	}
 
 	ret = handle_mmio_page_fault(vcpu, gpa, true);
+	vcpu->arch.gpa_available = true;
 	if (likely(ret == RET_MMIO_PF_EMULATE))
 		return x86_emulate_instruction(vcpu, gpa, 0, NULL, 0) ==
 					      EMULATE_DONE;
@@ -8520,6 +8522,7 @@
 	u32 vectoring_info = vmx->idt_vectoring_info;
 
 	trace_kvm_exit(exit_reason, vcpu, KVM_ISA_VMX);
+	vcpu->arch.gpa_available = false;
 
 	/*
 	 * Flush logged GPAs PML buffer, this will make dirty_bitmap more