linux-kernel - [RFC Part2 PATCH v3 24/26] KVM: SVM: Clear C-bit from the page fault address

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Message-Id: <20170724200303.12197-25-brijesh.singh@amd.com>
Date:   Mon, 24 Jul 2017 15:03:01 -0500
From:   Brijesh Singh <brijesh.singh@....com>
To:     linux-kernel@...r.kernel.org, x86@...nel.org, kvm@...r.kernel.org
Cc:     Thomas Gleixner <tglx@...utronix.de>, Borislav Petkov <bp@...e.de>,
        Joerg Roedel <joro@...tes.org>,
        "Michael S . Tsirkin" <mst@...hat.com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        \"Radim Krčmář\" 
        <rkrcmar@...hat.com>, Tom Lendacky <thomas.lendacky@....com>,
        Brijesh Singh <brijesh.singh@....com>
Subject: [RFC Part2 PATCH v3 24/26] KVM: SVM: Clear C-bit from the page fault address

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

Signed-off-by: Brijesh Singh <brijesh.singh@....com>
---
 arch/x86/kvm/svm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 0bbd050..64b9f60 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -2321,7 +2321,7 @@ 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,
-- 
2.9.4