[PATCH 5.10 096/530] KVM: SVM: Inject #GP on guest MSR_TSC_AUX accesses if RDTSCP unsupported
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-05-12 15:37:12
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From: Sean Christopherson <seanjc@google.com>
commit 6f2b296aa6432d8274e258cc3220047ca04f5de0 upstream.
Inject #GP on guest accesses to MSR_TSC_AUX if RDTSCP is unsupported in
the guest's CPUID model.
Fixes: 46896c73c1a4 ("KVM: svm: add support for RDTSCP")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: [off-list ref]
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/x86/kvm/svm/svm.c | 7 +++++++
1 file changed, 7 insertions(+)
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c@@ -2519,6 +2519,9 @@ static int svm_get_msr(struct kvm_vcpu * case MSR_TSC_AUX: if (!boot_cpu_has(X86_FEATURE_RDTSCP)) return 1; + if (!msr_info->host_initiated && + !guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP)) + return 1; msr_info->data = svm->tsc_aux; break; /*
@@ -2713,6 +2716,10 @@ static int svm_set_msr(struct kvm_vcpu * if (!boot_cpu_has(X86_FEATURE_RDTSCP)) return 1; + if (!msr->host_initiated && + !guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP)) + return 1; + /* * This is rare, so we update the MSR here instead of using * direct_access_msrs. Doing that would require a rdmsr in