Limit kvm_pmu_cap.num_counters_gp during kvm_init_pmu_capability() based
on the vendor PMU capabilities so that consuming num_counters_gp naturally
does the right thing. This fixes a mostly theoretical bug where KVM could
over-report its PMU support in KVM_GET_SUPPORTED_CPUID for leaf 0xA, e.g.
if the number of counters reported by perf is greater than KVM's
hardcoded internal limit. Incorporating input from the AMD PMU also
avoids over-reporting MSRs to save when running on AMD.
Link: https://lore.kernel.org/r/20230124234905.3774678-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
void (*cleanup)(struct kvm_vcpu *vcpu);
const u64 EVENTSEL_EVENT;
+ const int MAX_NR_GP_COUNTERS;
};
void kvm_pmu_ops_update(const struct kvm_pmu_ops *pmu_ops);
extern struct x86_pmu_capability kvm_pmu_cap;
-static inline void kvm_init_pmu_capability(void)
+static inline void kvm_init_pmu_capability(const struct kvm_pmu_ops *pmu_ops)
{
bool is_intel = boot_cpu_data.x86_vendor == X86_VENDOR_INTEL;
}
kvm_pmu_cap.version = min(kvm_pmu_cap.version, 2);
+ kvm_pmu_cap.num_counters_gp = min(kvm_pmu_cap.num_counters_gp,
+ pmu_ops->MAX_NR_GP_COUNTERS);
kvm_pmu_cap.num_counters_fixed = min(kvm_pmu_cap.num_counters_fixed,
KVM_PMC_MAX_FIXED);
}
.init = amd_pmu_init,
.reset = amd_pmu_reset,
.EVENTSEL_EVENT = AMD64_EVENTSEL_EVENT,
+ .MAX_NR_GP_COUNTERS = KVM_AMD_PMC_MAX_GENERIC,
};
.deliver_pmi = intel_pmu_deliver_pmi,
.cleanup = intel_pmu_cleanup,
.EVENTSEL_EVENT = ARCH_PERFMON_EVENTSEL_EVENT,
+ .MAX_NR_GP_COUNTERS = KVM_INTEL_PMC_MAX_GENERIC,
};
break;
case MSR_ARCH_PERFMON_PERFCTR0 ... MSR_ARCH_PERFMON_PERFCTR_MAX:
if (msrs_to_save_all[i] - MSR_ARCH_PERFMON_PERFCTR0 >=
- min(KVM_INTEL_PMC_MAX_GENERIC, kvm_pmu_cap.num_counters_gp))
+ kvm_pmu_cap.num_counters_gp)
continue;
break;
case MSR_ARCH_PERFMON_EVENTSEL0 ... MSR_ARCH_PERFMON_EVENTSEL_MAX:
if (msrs_to_save_all[i] - MSR_ARCH_PERFMON_EVENTSEL0 >=
- min(KVM_INTEL_PMC_MAX_GENERIC, kvm_pmu_cap.num_counters_gp))
+ kvm_pmu_cap.num_counters_gp)
continue;
break;
case MSR_IA32_XFD:
if (boot_cpu_has(X86_FEATURE_XSAVES))
rdmsrl(MSR_IA32_XSS, host_xss);
- kvm_init_pmu_capability();
+ kvm_init_pmu_capability(ops->pmu_ops);
r = ops->hardware_setup();
if (r != 0)