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KVM: x86/pmu: Restrict GLOBAL_{CTRL,STATUS}, fixed PMCs, and PEBS to PMU v2+

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Restrict support for GLOBAL_CTRL, GLOBAL_STATUS, fixed PMCs, and PEBS to
v2 or later vPMUs.  The SDM explicitly states that GLOBAL_{CTRL,STATUS} and
fixed counters were introduced with PMU v2, and PEBS has hard dependencies
on fixed counters and the bitmap MSR layouts established by PMU v2.

Reported-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Tested-by: Xudong Hao <xudong.hao@intel.com>
Link: https://lore.kernel.org/r/20250806195706.1650976-32-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
This commit is contained in:
Sean Christopherson
2025-08-06 12:56:53 -07:00
parent 9bae7a0863
commit c49aa98376
1 changed files with 25 additions and 26 deletions
Download Patch File Download Diff File Expand all files Collapse all files
arch/x86/kvm/vmx/pmu_intel.c
+25 -26
View File
@@ -541,16 +541,33 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
kvm_pmu_cap.events_mask_len);
pmu->available_event_types = ~entry->ebx & (BIT_ULL(eax.split.mask_length) - 1);
if (pmu->version == 1) {
pmu->nr_arch_fixed_counters = 0;
} else {
pmu->nr_arch_fixed_counters = min_t(int, edx.split.num_counters_fixed,
kvm_pmu_cap.num_counters_fixed);
edx.split.bit_width_fixed = min_t(int, edx.split.bit_width_fixed,
kvm_pmu_cap.bit_width_fixed);
pmu->counter_bitmask[KVM_PMC_FIXED] = BIT_ULL(edx.split.bit_width_fixed) - 1;
entry = kvm_find_cpuid_entry_index(vcpu, 7, 0);
if (entry &&
(boot_cpu_has(X86_FEATURE_HLE) || boot_cpu_has(X86_FEATURE_RTM)) &&
(entry->ebx & (X86_FEATURE_HLE|X86_FEATURE_RTM))) {
pmu->reserved_bits ^= HSW_IN_TX;
pmu->raw_event_mask |= (HSW_IN_TX|HSW_IN_TX_CHECKPOINTED);
}
perf_capabilities = vcpu_get_perf_capabilities(vcpu);
if (intel_pmu_lbr_is_compatible(vcpu) &&
(perf_capabilities & PERF_CAP_LBR_FMT))
memcpy(&lbr_desc->records, &vmx_lbr_caps, sizeof(vmx_lbr_caps));
else
lbr_desc->records.nr = 0;
if (lbr_desc->records.nr)
bitmap_set(pmu->all_valid_pmc_idx, INTEL_PMC_IDX_FIXED_VLBR, 1);
if (pmu->version == 1)
return;
pmu->nr_arch_fixed_counters = min_t(int, edx.split.num_counters_fixed,
kvm_pmu_cap.num_counters_fixed);
edx.split.bit_width_fixed = min_t(int, edx.split.bit_width_fixed,
kvm_pmu_cap.bit_width_fixed);
pmu->counter_bitmask[KVM_PMC_FIXED] = BIT_ULL(edx.split.bit_width_fixed) - 1;
intel_pmu_enable_fixed_counter_bits(pmu, INTEL_FIXED_0_KERNEL |
INTEL_FIXED_0_USER |
INTEL_FIXED_0_ENABLE_PMI);
@@ -571,24 +588,6 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
pmu->global_status_rsvd &=
~MSR_CORE_PERF_GLOBAL_OVF_CTRL_TRACE_TOPA_PMI;
entry = kvm_find_cpuid_entry_index(vcpu, 7, 0);
if (entry &&
(boot_cpu_has(X86_FEATURE_HLE) || boot_cpu_has(X86_FEATURE_RTM)) &&
(entry->ebx & (X86_FEATURE_HLE|X86_FEATURE_RTM))) {
pmu->reserved_bits ^= HSW_IN_TX;
pmu->raw_event_mask |= (HSW_IN_TX|HSW_IN_TX_CHECKPOINTED);
}
perf_capabilities = vcpu_get_perf_capabilities(vcpu);
if (intel_pmu_lbr_is_compatible(vcpu) &&
(perf_capabilities & PERF_CAP_LBR_FMT))
memcpy(&lbr_desc->records, &vmx_lbr_caps, sizeof(vmx_lbr_caps));
else
lbr_desc->records.nr = 0;
if (lbr_desc->records.nr)
bitmap_set(pmu->all_valid_pmc_idx, INTEL_PMC_IDX_FIXED_VLBR, 1);
if (perf_capabilities & PERF_CAP_PEBS_FORMAT) {
if (perf_capabilities & PERF_CAP_PEBS_BASELINE) {
pmu->pebs_enable_rsvd = counter_rsvd;