From: Like Xu <likexu@xxxxxxxxxxx>
Whenever an MSR is part of KVM_GET_MSR_INDEX_LIST, as is the case for
MSR_K7_EVNTSEL0 or MSR_F15H_PERF_CTL0, it has to be always retrievable
and settable with KVM_GET_MSR and KVM_SET_MSR.
Accept a zero value for these MSRs to obey the contract.
Signed-off-by: Like Xu <likexu@xxxxxxxxxxx>
---
Note, if !enable_pmu, it is easy to reproduce and verify it with selftest.
arch/x86/kvm/pmu.c | 8 ++++++++
arch/x86/kvm/svm/pmu.c | 11 ++++++++++-
2 files changed, 18 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index 7a74691de223..3575a3746bf9 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -439,11 +439,19 @@ static void kvm_pmu_mark_pmc_in_use(struct kvm_vcpu *vcpu, u32 msr)
int kvm_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
{
+ if (msr_info->host_initiated && !vcpu->kvm->arch.enable_pmu) {
+ msr_info->data = 0;
+ return 0;
+ }
+
return static_call(kvm_x86_pmu_get_msr)(vcpu, msr_info);
}
int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
{
+ if (msr_info->host_initiated && !vcpu->kvm->arch.enable_pmu)
+ return !!msr_info->data;
+
kvm_pmu_mark_pmc_in_use(vcpu, msr_info->index);
return static_call(kvm_x86_pmu_set_msr)(vcpu, msr_info);
}
diff --git a/arch/x86/kvm/svm/pmu.c b/arch/x86/kvm/svm/pmu.c
index 256244b8f89c..fe520b2649b5 100644
--- a/arch/x86/kvm/svm/pmu.c
+++ b/arch/x86/kvm/svm/pmu.c
@@ -182,7 +182,16 @@ static struct kvm_pmc *amd_rdpmc_ecx_to_pmc(struct kvm_vcpu *vcpu,
static bool amd_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr, bool host_initiated)
{
/* All MSRs refer to exactly one PMC, so msr_idx_to_pmc is enough. */
- return false;
+ if (!host_initiated)
+ return false;
+
+ switch (msr) {
+ case MSR_K7_EVNTSEL0 ... MSR_K7_PERFCTR3:
+ case MSR_F15H_PERF_CTL0 ... MSR_F15H_PERF_CTR5:
+ return true;
+ default:
+ return false;
+ }
}
static struct kvm_pmc *amd_msr_idx_to_pmc(struct kvm_vcpu *vcpu, u32 msr)
--
2.36.1
