diff options
| author | Sean Christopherson <seanjc@google.com> | 2023-06-06 18:02:05 -0700 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2023-08-02 16:44:36 -0700 |
| commit | 6d88d0ee5de142921598e5c0041792bbd860913d (patch) | |
| tree | 3007935e0c04149761293bab3900647955fb3ce0 | |
| parent | bc9658999b3e44cbad964fe9fbab5a25bd4f5ed3 (diff) | |
KVM: x86/pmu: Require nr fixed_pmc_events to match nr max fixed counters
Assert that the number of known fixed_pmc_events matches the max number of
fixed counters supported by KVM, and clean up related code.
Opportunistically extend setup_fixed_pmc_eventsel()'s use of
array_index_nospec() to cover fixed_counters, as nr_arch_fixed_counters is
set based on userspace input (but capped using KVM-controlled values).
Link: https://lore.kernel.org/r/20230607010206.1425277-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
| -rw-r--r-- | arch/x86/kvm/vmx/pmu_intel.c | 19 |
1 files changed, 9 insertions, 10 deletions
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c index db23697f3141..f2efa0bf7ae8 100644 --- a/arch/x86/kvm/vmx/pmu_intel.c +++ b/arch/x86/kvm/vmx/pmu_intel.c @@ -468,16 +468,17 @@ static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) static void setup_fixed_pmc_eventsel(struct kvm_pmu *pmu) { - size_t size = ARRAY_SIZE(fixed_pmc_events); - struct kvm_pmc *pmc; - u32 event; int i; + BUILD_BUG_ON(ARRAY_SIZE(fixed_pmc_events) != KVM_PMC_MAX_FIXED); + for (i = 0; i < pmu->nr_arch_fixed_counters; i++) { - pmc = &pmu->fixed_counters[i]; - event = fixed_pmc_events[array_index_nospec(i, size)]; + int index = array_index_nospec(i, KVM_PMC_MAX_FIXED); + struct kvm_pmc *pmc = &pmu->fixed_counters[index]; + u32 event = fixed_pmc_events[index]; + pmc->eventsel = (intel_arch_events[event].unit_mask << 8) | - intel_arch_events[event].eventsel; + intel_arch_events[event].eventsel; } } @@ -538,10 +539,8 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu) if (pmu->version == 1) { pmu->nr_arch_fixed_counters = 0; } else { - pmu->nr_arch_fixed_counters = - min3(ARRAY_SIZE(fixed_pmc_events), - (size_t) edx.split.num_counters_fixed, - (size_t)kvm_pmu_cap.num_counters_fixed); + 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] = |