[PATCH] KVM: SVM: Fix svm the vmexit error_code of WRMSR

[Haiwei Li]

 From 1f755f75dfd73ad7cabb0e0f43e9993dd9f69120 Mon Sep 17 00:00:00 2001
From: Haiwei Li <lihaiwei@xxxxxxxxxxx>
Date: Mon, 2 Mar 2020 19:19:59 +0800
Subject: [PATCH] KVM: SVM: Fix svm the vmexit error_code of WRMSR

In svm, exit_code of write_msr is not EXIT_REASON_MSR_WRITE which
belongs to vmx.

According to amd manual, SVM_EXIT_MSR(7ch) is the exit_code of VMEXIT_MSR
due to RDMSR or WRMSR access to protected MSR. Additionally, the processor
indicates in the VMCB's EXITINFO1 whether a RDMSR(EXITINFO1=0) or
WRMSR(EXITINFO1=1) was intercepted.

Signed-off-by: Haiwei Li <lihaiwei@xxxxxxxxxxx>
---
  arch/x86/kvm/svm.c | 3 ++-
  1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index fd3fc9f..ef71755 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -6296,7 +6296,8 @@ static void svm_handle_exit_irqoff(struct kvm_vcpu
*vcpu,
         enum exit_fastpath_completion *exit_fastpath)
  {
         if (!is_guest_mode(vcpu) &&
-               to_svm(vcpu)->vmcb->control.exit_code ==
EXIT_REASON_MSR_WRITE)
+               (to_svm(vcpu)->vmcb->control.exit_code == SVM_EXIT_MSR) &&
+               (to_svm(vcpu)->vmcb->control.exit_info_1 & 1))
                 *exit_fastpath = handle_fastpath_set_msr_irqoff(vcpu);
  }

--
1.8.3.1