diff mbox series

[v8,2/4] kvm: vmx: Enable MSR TEST_CTRL for guest

Message ID 20200414063129.133630-3-xiaoyao.li@intel.com (mailing list archive)
State New, archived
Headers show
Series KVM: Add virtualization support of split lock detection | expand

Commit Message

Xiaoyao Li April 14, 2020, 6:31 a.m. UTC 
Unconditionally allow the guest to read and zero-write MSR TEST_CTRL.

This matches the fact that most Intel CPUs support MSR TEST_CTRL, and
it also alleviates the effort to handle wrmsr/rdmsr when split lock
detection is exposed to the guest in a future patch.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
---
 arch/x86/kvm/vmx/vmx.c | 8 ++++++++
 1 file changed, 8 insertions(+)
diff mbox series

Patch

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 83050977490c..ae394ed174cd 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -1789,6 +1789,9 @@  static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 	u32 index;
 
 	switch (msr_info->index) {
+	case MSR_TEST_CTRL:
+		msr_info->data = 0;
+		break;
 #ifdef CONFIG_X86_64
 	case MSR_FS_BASE:
 		msr_info->data = vmcs_readl(GUEST_FS_BASE);
@@ -1942,6 +1945,11 @@  static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 	u32 index;
 
 	switch (msr_index) {
+	case MSR_TEST_CTRL:
+		if (data)
+			return 1;
+
+		break;
 	case MSR_EFER:
 		ret = kvm_set_msr_common(vcpu, msr_info);
 		break;