4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Paolo Bonzini <pbonzini@xxxxxxxxxx>
commit cd28325249a1ca0d771557ce823e0308ad629f98 upstream
This lets userspace read the MSR_IA32_ARCH_CAPABILITIES and check that all
requested features are available on the host.
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/kvm/x86.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1015,6 +1015,7 @@ static unsigned num_emulated_msrs;
static u32 msr_based_features[] = {
MSR_F10H_DECFG,
MSR_IA32_UCODE_REV,
+ MSR_IA32_ARCH_CAPABILITIES,
};
static unsigned int num_msr_based_features;
@@ -1023,7 +1024,8 @@ static int kvm_get_msr_feature(struct kv
{
switch (msr->index) {
case MSR_IA32_UCODE_REV:
- rdmsrl(msr->index, msr->data);
+ case MSR_IA32_ARCH_CAPABILITIES:
+ rdmsrl_safe(msr->index, &msr->data);
break;
default:
if (kvm_x86_ops->get_msr_feature(msr))
