Commit 672ff6cf authored Mar 25, 2019 by Liran Alon Committed by Paolo Bonzini Apr 16, 2019

KVM: x86: Raise #GP when guest vCPU do not support PMU



Before this change, reading a VMware pseduo PMC will succeed even when
PMU is not supported by guest. This can easily be seen by running
kvm-unit-test vmware_backdoors with "-cpu host,-pmu" option.

Reviewed-by: Mihai Carabas <mihai.carabas@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

parent 1811d979

arch/x86/kvm/pmu.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -281,9 +281,13 @@ static int kvm_pmu_rdpmc_vmware(struct kvm_vcpu vcpu, unsigned idx, u64 data)
		int kvm_pmu_rdpmc(struct kvm_vcpu vcpu, unsigned idx, u64 data)
		{
		bool fast_mode = idx & (1u << 31);
		struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
		struct kvm_pmc *pmc;
		u64 ctr_val;

		if (!pmu->version)
		return 1;

		if (is_vmware_backdoor_pmc(idx))
		return kvm_pmu_rdpmc_vmware(vcpu, idx, data);

Admin message