The vmexit path on SVM needs to restore the KERNEL_GS_BASE MSR in order to savely execute the NMI handler. Otherwise a pending NMI can occur after the STGI instruction and crash the machine. This makes it impossible to run perf and kvm in parallel on an AMD machine in a stable way. Cc: stable@xxxxxxxxxx Signed-off-by: Joerg Roedel <joerg.roedel@xxxxxxx> --- arch/x86/kvm/svm.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 25bd1bc..8b9bc72 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -3637,6 +3637,7 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu) #ifdef CONFIG_X86_64 wrmsrl(MSR_GS_BASE, svm->host.gs_base); + wrmsrl(MSR_KERNEL_GS_BASE, current->thread.gs); #else loadsegment(fs, svm->host.fs); #endif -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
