On 8/5/2023 2:55 AM, Sean Christopherson wrote:
On Thu, Aug 03, 2023, Yang Weijiang wrote:
Add all CET MSRs including the synthesized GUEST_SSP to report list.
PL{0,1,2}_SSP are independent to host XSAVE management with later
patches. MSR_IA32_U_CET and MSR_IA32_PL3_SSP are XSAVE-managed on
host side. MSR_IA32_S_CET/MSR_IA32_INT_SSP_TAB/MSR_KVM_GUEST_SSP
are not XSAVE-managed.
[...]
}
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 82e3dafc5453..6e6292915f8c 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -362,6 +362,16 @@ static inline bool kvm_mpx_supported(void)
== (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR);
}
+#define CET_XSTATE_MASK (XFEATURE_MASK_CET_USER)
This is funky. As of this patch, KVM reports MSR_IA32_S_CET, a supervisor MSR,
but does not require XFEATURE_MASK_CET_KERNEL. That eventually comes along with
"KVM:x86: Enable guest CET supervisor xstate bit support", but as of this patch
KVM is busted.
The whole cpuid_count() code in that patch shouldn't exist, so the easiest thing
is to just fold the KVM_SUPPORTED_XSS and CET_XSTATE_MASK changes from that patch
into this one.
I screwed it up when tried to make it clearer :-/
Will do it, thanks!