From 4f1fa2a1bbeb2feca436d2c86bf6f78dc4e5e4c4 Mon Sep 17 00:00:00 2001 From: Like Xu Date: Mon, 19 Sep 2022 17:10:07 +0800 Subject: KVM: x86/pmu: Limit the maximum number of supported Intel GP counters The Intel Architectural IA32_PMCx MSRs addresses range allows for a maximum of 8 GP counters, and KVM cannot address any more. Introduce a local macro (named KVM_INTEL_PMC_MAX_GENERIC) and use it consistently to refer to the number of counters supported by KVM, thus avoiding possible out-of-bound accesses. Suggested-by: Jim Mattson Signed-off-by: Like Xu Reviewed-by: Jim Mattson Message-Id: <20220919091008.60695-2-likexu@tencent.com> Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'arch/x86/include/asm/kvm_host.h') diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 7551b6f9c31c..286f6130dcb4 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -501,6 +501,10 @@ struct kvm_pmc { bool intr; }; +/* More counters may conflict with other existing Architectural MSRs */ +#define KVM_INTEL_PMC_MAX_GENERIC 8 +#define MSR_ARCH_PERFMON_PERFCTR_MAX (MSR_ARCH_PERFMON_PERFCTR0 + KVM_INTEL_PMC_MAX_GENERIC - 1) +#define MSR_ARCH_PERFMON_EVENTSEL_MAX (MSR_ARCH_PERFMON_EVENTSEL0 + KVM_INTEL_PMC_MAX_GENERIC - 1) #define KVM_PMC_MAX_FIXED 3 struct kvm_pmu { unsigned nr_arch_gp_counters; @@ -516,7 +520,7 @@ struct kvm_pmu { u64 reserved_bits; u64 raw_event_mask; u8 version; - struct kvm_pmc gp_counters[INTEL_PMC_MAX_GENERIC]; + struct kvm_pmc gp_counters[KVM_INTEL_PMC_MAX_GENERIC]; struct kvm_pmc fixed_counters[KVM_PMC_MAX_FIXED]; struct irq_work irq_work; DECLARE_BITMAP(reprogram_pmi, X86_PMC_IDX_MAX); -- cgit v1.2.3