4.20-stable review patch. If anyone has any objections, please let me know.
------------------
[ Upstream commit e87555e550cef4941579cd879759a7c0dee24e68 ]
AMD doesn't seem to implement MSR_IA32_MCG_EXT_CTL and svm code in kvm
knows nothing about it, however, this MSR is among emulated_msrs and
thus returned with KVM_GET_MSR_INDEX_LIST. The consequent KVM_GET_MSRS,
of course, fails.
Report the MSR as unsupported to not confuse userspace.
Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Signed-off-by: Radim Krčmář <rkrcmar@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/x86/kvm/svm.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 101f53ccf571..11641d9e7f6f 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -5836,6 +5836,13 @@ static bool svm_cpu_has_accelerated_tpr(void)
static bool svm_has_emulated_msr(int index)
{
+ switch (index) {
+ case MSR_IA32_MCG_EXT_CTL:
+ return false;
+ default:
+ break;
+ }
+
return true;
}
--
2.19.1
