Re: [PATCH v14 09/13] KVM: x86: Report CET MSRs as to-be-saved if CET is supported

From: Paolo Bonzini
Date: Thu Jan 28 2021 - 12:51:02 EST


On 06/11/20 02:16, Yang Weijiang wrote:
Report all CET MSRs, including the synthetic GUEST_SSP MSR, as
to-be-saved, e.g. for migration, if CET is supported by KVM.

Co-developed-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Signed-off-by: Yang Weijiang <weijiang.yang@xxxxxxxxx>
---
arch/x86/kvm/x86.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 751b62e871e5..d573cadf5baf 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1248,6 +1248,8 @@ static const u32 msrs_to_save_all[] = {
MSR_ARCH_PERFMON_EVENTSEL0 + 16, MSR_ARCH_PERFMON_EVENTSEL0 + 17,
MSR_IA32_XSS,
+ MSR_IA32_U_CET, MSR_IA32_S_CET, MSR_IA32_INT_SSP_TAB, MSR_KVM_GUEST_SSP,
+ MSR_IA32_PL0_SSP, MSR_IA32_PL1_SSP, MSR_IA32_PL2_SSP, MSR_IA32_PL3_SSP,
};
static u32 msrs_to_save[ARRAY_SIZE(msrs_to_save_all)];
@@ -5761,6 +5763,13 @@ static void kvm_init_msr_list(void)
if (!supported_xss)
continue;
break;
+ case MSR_IA32_U_CET:
+ case MSR_IA32_S_CET:
+ case MSR_IA32_INT_SSP_TAB:
+ case MSR_IA32_PL0_SSP ... MSR_IA32_PL3_SSP:
+ if (!kvm_cet_supported())
+ continue;
+ break;
default:
break;
}


Missing "case MSR_KVM_GUEST_SSP".

Paolo