Am 13.01.2011 16:22, Joerg Roedel wrote: > 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 Doesn't this also obsolete the wrmsrl(MSR_KERNEL_GS_BASE) in svm_vcpu_put? Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux -- 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
