diff options
| author | Like Xu <likexu@tencent.com> | 2023-06-03 03:10:55 +0200 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2023-06-07 02:31:44 +0200 |
| commit | 1c2bf8a6b045a6ac4e75a7a07fde70db63e5a380 (patch) | |
| tree | 8bf7f1b2e759dd2f19e65aa636cb0f11a71aa8de /arch/x86/kvm | |
| parent | KVM: x86/pmu: Advertise PERFCTR_CORE iff the min nr of counters is met (diff) | |
| download | linux-1c2bf8a6b045a6ac4e75a7a07fde70db63e5a380.tar.xz linux-1c2bf8a6b045a6ac4e75a7a07fde70db63e5a380.zip | |
KVM: x86/pmu: Constrain the num of guest counters with kvm_pmu_cap
Cap the number of general purpose counters enumerated on AMD to what KVM
actually supports, i.e. don't allow userspace to coerce KVM into thinking
there are more counters than actually exist, e.g. by enumerating
X86_FEATURE_PERFCTR_CORE in guest CPUID when its not supported.
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Like Xu <likexu@tencent.com>
[sean: massage changelog]
Link: https://lore.kernel.org/r/20230603011058.1038821-10-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Diffstat (limited to 'arch/x86/kvm')
| -rw-r--r-- | arch/x86/kvm/svm/pmu.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/x86/kvm/svm/pmu.c b/arch/x86/kvm/svm/pmu.c index e5c69062a909..c03958063a76 100644 --- a/arch/x86/kvm/svm/pmu.c +++ b/arch/x86/kvm/svm/pmu.c @@ -170,6 +170,9 @@ static void amd_pmu_refresh(struct kvm_vcpu *vcpu) else pmu->nr_arch_gp_counters = AMD64_NUM_COUNTERS; + pmu->nr_arch_gp_counters = min_t(unsigned int, pmu->nr_arch_gp_counters, + kvm_pmu_cap.num_counters_gp); + pmu->counter_bitmask[KVM_PMC_GP] = ((u64)1 << 48) - 1; pmu->reserved_bits = 0xfffffff000280000ull; pmu->raw_event_mask = AMD64_RAW_EVENT_MASK; |