[PATCH v2 4/5] kvm: x86: Add IA32_XSS to the emulated_msrs list

[Aaron Lewis <aaronlewis@google.com>]

Add IA32_XSS to the list of emulated MSRs if it is supported in the
guest.  At the moment, the guest IA32_XSS must be zero, but this change
prepares for expanded support in the future.

Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Aaron Lewis <aaronlewis@google.com>
---
 arch/x86/kvm/svm.c     | 12 +++++++-----
 arch/x86/kvm/vmx/vmx.c |  2 ++
 arch/x86/kvm/x86.c     |  1 +
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 1953898e37ce..e23a5013c812 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -498,6 +498,11 @@ static inline bool avic_vcpu_is_running(struct kvm_vcpu *vcpu)
 	return (READ_ONCE(*entry) & AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK);
 }
 
+static bool svm_xsaves_supported(void)
+{
+	return boot_cpu_has(X86_FEATURE_XSAVES);
+}
+
 static void recalc_intercepts(struct vcpu_svm *svm)
 {
 	struct vmcb_control_area *c, *h;
@@ -5871,6 +5876,8 @@ static bool svm_has_emulated_msr(int index)
 	case MSR_IA32_MCG_EXT_CTL:
 	case MSR_IA32_VMX_BASIC ... MSR_IA32_VMX_VMFUNC:
 		return false;
+	case MSR_IA32_XSS:
+		return svm_xsaves_supported();
 	default:
 		break;
 	}
@@ -5963,11 +5970,6 @@ static bool svm_mpx_supported(void)
 	return false;
 }
 
-static bool svm_xsaves_supported(void)
-{
-	return boot_cpu_has(X86_FEATURE_XSAVES);
-}
-
 static bool svm_umip_emulated(void)
 {
 	return false;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 18bea844fffc..4ba62ebd8703 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6272,6 +6272,8 @@ static bool vmx_has_emulated_msr(int index)
 	case MSR_AMD64_VIRT_SPEC_CTRL:
 		/* This is AMD only.  */
 		return false;
+	case MSR_IA32_XSS:
+		return vmx_xsaves_supported();
 	default:
 		return true;
 	}
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 2104e21855fc..e3b7dbb8be8f 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1227,6 +1227,7 @@ static u32 emulated_msrs[] = {
 	MSR_MISC_FEATURES_ENABLES,
 	MSR_AMD64_VIRT_SPEC_CTRL,
 	MSR_IA32_POWER_CTL,
+	MSR_IA32_XSS,
 
 	/*
 	 * The following list leaves out MSRs whose values are determined
-- 
2.23.0.700.g56cf767bdb-goog