| Message ID | 20190925213721.21245-2-bigeasy@linutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] KVM: x86: svm: Pass XSAVES to guest if available on host | expand |
On Wed, Sep 25, 2019 at 2:37 PM Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote: > > In commit > 55412b2eda2b7 ("kvm: x86: Add kvm_x86_ops hook that enables XSAVES for guest") > > XSAVES was enabled on VMX with a few additional tweaks and was always > disabled on SVM. Before ZEN XSAVES was not available so it made no > difference. With Zen it is possible to expose it to the guest if it is > available on the host. > I didn't find anything close to VMX's "VM-Execution Controls" and > exposing this flag based on the CPUID flags cause no harm so far. > > Expose the XSAVES flag to the guest if the host supports it. > > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> > --- > arch/x86/kvm/svm.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c > index e0368076a1ef9..3878eb766fa39 100644 > --- a/arch/x86/kvm/svm.c > +++ b/arch/x86/kvm/svm.c > @@ -5992,7 +5992,7 @@ static bool svm_mpx_supported(void) > > static bool svm_xsaves_supported(void) > { > - return false; > + return boot_cpu_has(X86_FEATURE_XSAVES); > } > > static bool svm_umip_emulated(void) > -- > 2.23.0 This is inadequate. Please read the existing thread, "[Patch] KVM: SVM: Fix svm_xsaves_supported." Aaron Lewis is working on completing this as we speak.
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index e0368076a1ef9..3878eb766fa39 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -5992,7 +5992,7 @@ static bool svm_mpx_supported(void) static bool svm_xsaves_supported(void) { - return false; + return boot_cpu_has(X86_FEATURE_XSAVES); } static bool svm_umip_emulated(void)
In commit 55412b2eda2b7 ("kvm: x86: Add kvm_x86_ops hook that enables XSAVES for guest") XSAVES was enabled on VMX with a few additional tweaks and was always disabled on SVM. Before ZEN XSAVES was not available so it made no difference. With Zen it is possible to expose it to the guest if it is available on the host. I didn't find anything close to VMX's "VM-Execution Controls" and exposing this flag based on the CPUID flags cause no harm so far. Expose the XSAVES flag to the guest if the host supports it. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- arch/x86/kvm/svm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)