4 files changed, 12 insertions, 5 deletions

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 16d588c3e3c1..631c3f59109a 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -486,6 +486,7 @@ struct kvm_vcpu_arch {
 	u64 smbase;
 	bool tpr_access_reporting;
 	u64 ia32_xss;
+	u64 microcode_version;
 
 	/*
 	 * Paging state of the vcpu
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 44a6f7fa2279..c855080c7a71 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1569,6 +1569,7 @@ static void svm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
 	u32 dummy;
 	u32 eax = 1;
 
+	vcpu->arch.microcode_version = 0x01000065;
 	svm->spec_ctrl = 0;
 	svm->virt_spec_ctrl = 0;
 
@@ -3585,9 +3586,6 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 
 		msr_info->data = svm->virt_spec_ctrl;
 		break;
-	case MSR_IA32_UCODE_REV:
-		msr_info->data = 0x01000065;
-		break;
 	case MSR_F15H_IC_CFG: {
 
 		int family, model;
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 3e04e19dd5b1..4596791dbb81 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -5481,6 +5481,7 @@ static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
 	u64 cr0;
 
 	vmx->rmode.vm86_active = 0;
+	vcpu->arch.microcode_version = 0x100000000ULL;
 	vmx->spec_ctrl = 0;
 
 	vmx->soft_vnmi_blocked = 0;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index bd0e68163b5f..8749967a1d27 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1014,6 +1014,7 @@ static unsigned num_emulated_msrs;
  */
 static u32 msr_based_features[] = {
 	MSR_F10H_DECFG,
+	MSR_IA32_UCODE_REV,
 };
 
 static unsigned int num_msr_based_features;
@@ -1021,6 +1022,9 @@ static unsigned int num_msr_based_features;
 static int kvm_get_msr_feature(struct kvm_msr_entry *msr)
 {
 	switch (msr->index) {
+	case MSR_IA32_UCODE_REV:
+		rdmsrl(msr->index, msr->data);
+		break;
 	default:
 		if (kvm_x86_ops->get_msr_feature(msr))
 			return 1;
@@ -2157,13 +2161,16 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 
 	switch (msr) {
 	case MSR_AMD64_NB_CFG:
-	case MSR_IA32_UCODE_REV:
 	case MSR_IA32_UCODE_WRITE:
 	case MSR_VM_HSAVE_PA:
 	case MSR_AMD64_PATCH_LOADER:
 	case MSR_AMD64_BU_CFG2:
 		break;
 
+	case MSR_IA32_UCODE_REV:
+		if (msr_info->host_initiated)
+			vcpu->arch.microcode_version = data;
+		break;
 	case MSR_EFER:
 		return set_efer(vcpu, data);
 	case MSR_K7_HWCR:
@@ -2438,7 +2445,7 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 		msr_info->data = 0;
 		break;
 	case MSR_IA32_UCODE_REV:
-		msr_info->data = 0x100000000ULL;
+		msr_info->data = vcpu->arch.microcode_version;
 		break;
 	case MSR_MTRRcap:
 	case 0x200 ... 0x2ff: