KVM: SVM: Clear C-bit from the page fault address

When SEV is active, on #VMEXIT the  page fault address will contain the
C-bit. We must clear the C-bit before handling the fault.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>

arch/x86/kvm/svm.c

@@ -2430,7 +2430,7 @@ static void svm_set_dr7(struct kvm_vcpu *vcpu, unsigned long value)
 
 static int pf_interception(struct vcpu_svm *svm)
 {
-	u64 fault_address = svm->vmcb->control.exit_info_2;
+	u64 fault_address = __sme_clr(svm->vmcb->control.exit_info_2);
 	u64 error_code = svm->vmcb->control.exit_info_1;
 
 	return kvm_handle_page_fault(&svm->vcpu, error_code, fault_address,
@@ -2440,7 +2440,7 @@ static int pf_interception(struct vcpu_svm *svm)
 
 static int npf_interception(struct vcpu_svm *svm)
 {
-	u64 fault_address = svm->vmcb->control.exit_info_2;
+	u64 fault_address = __sme_clr(svm->vmcb->control.exit_info_2);
 	u64 error_code = svm->vmcb->control.exit_info_1;
 
 	trace_kvm_page_fault(fault_address, error_code);