[PATCH v15 01/14] KVM: x86: Report XSS as an MSR to be saved if there are supported features

From: Yang Weijiang
Date: Wed Feb 03 2021 - 06:23:12 EST


From: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>

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.

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 | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 76bce832cade..a657706358e8 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1255,6 +1255,8 @@ static const u32 msrs_to_save_all[] = {
MSR_ARCH_PERFMON_EVENTSEL0 + 12, MSR_ARCH_PERFMON_EVENTSEL0 + 13,
MSR_ARCH_PERFMON_EVENTSEL0 + 14, MSR_ARCH_PERFMON_EVENTSEL0 + 15,
MSR_ARCH_PERFMON_EVENTSEL0 + 16, MSR_ARCH_PERFMON_EVENTSEL0 + 17,
+
+ MSR_IA32_XSS,
};

static u32 msrs_to_save[ARRAY_SIZE(msrs_to_save_all)];
@@ -5795,6 +5797,10 @@ static void kvm_init_msr_list(void)
min(INTEL_PMC_MAX_GENERIC, x86_pmu.num_counters_gp))
continue;
break;
+ case MSR_IA32_XSS:
+ if (!supported_xss)
+ continue;
+ break;
default:
break;
}
--
2.26.2