The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 6f2b296aa6432d8274e258cc3220047ca04f5de0 Mon Sep 17 00:00:00 2001
From: Sean Christopherson <seanjc@xxxxxxxxxx>
Date: Fri, 23 Apr 2021 15:34:01 -0700
Subject: [PATCH] KVM: SVM: Inject #GP on guest MSR_TSC_AUX accesses if RDTSCP
unsupported
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@xxxxxxxxxxxxxxx
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Message-Id: <20210423223404.3860547-2-seanjc@xxxxxxxxxx>
Reviewed-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index cd8c333ed2dc..9ed9c7bd7cfd 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -2674,6 +2674,9 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
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;
/*
@@ -2892,6 +2895,10 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
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
