Re: [PATCH v3 06/21] KVM:x86: Report XSS as to-be-saved if there are supported features

Chao Gao
2023-05-24T07:06:57Z

On Thu, May 11, 2023 at 12:08:42AM -0400, Yang Weijiang wrote:
>From: Sean Christopherson <sean.j.christopherson@intel.com>
>
>Add MSR_IA32_XSS to the list of MSRs reported to userspace if
>supported_xss is non-zero, i.e. KVM supports at least one XSS based
>feature.

The changelog doesn't match what the patch does.

Do you need to check if supported_xss is non-zero in kvm_probe_msr_to_save(),
e.g.,
case MSR_IA32_XSS:
if (!kvm_caps.supported_xss)
return;
break;

>
>Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
>Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
>---
> arch/x86/kvm/x86.c | 1 +
> 1 file changed, 1 insertion(+)
>
>diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
>index e7f78fe79b32..33a780fe820b 100644
>--- a/arch/x86/kvm/x86.c
>+++ b/arch/x86/kvm/x86.c
>@@ -1454,6 +1454,7 @@ static const u32 msrs_to_save_base[] = {
> MSR_IA32_UMWAIT_CONTROL,
>
> MSR_IA32_XFD, MSR_IA32_XFD_ERR,
>+ MSR_IA32_XSS,
> };
>
> static const u32 msrs_to_save_pmu[] = {
>--
>2.27.0
>