Re: [PATCH v9 12/27] KVM: x86: Report XSS as to-be-saved if there are supported features

Chao Gao
2024-01-25T10:38:14Z

On Tue, Jan 23, 2024 at 06:41:45PM -0800, Yang Weijiang wrote:
>From: Sean Christopherson <seanjc@google.com>
>
>Add MSR_IA32_XSS to list of MSRs reported to userspace if supported_xss
>is non-zero, i.e. KVM supports at least one XSS based feature.
>
>Before enabling CET virtualization series, guest IA32_MSR_XSS is
>guaranteed to be 0, i.e., XSAVES/XRSTORS is executed in non-root mode
>with XSS == 0, which equals to the effect of XSAVE/XRSTOR.
>
>Signed-off-by: Sean Christopherson <seanjc@google.com>
>Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
>Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>

Reviewed-by: Chao Gao <chao.gao@intel.com>