On Thu, Mar 23, 2023, Mingwei Zhang wrote:
> > --- a/arch/x86/kvm/x86.h
> > +++ b/arch/x86/kvm/x86.h
> > @@ -3,6 +3,7 @@
> > #define ARCH_X86_KVM_X86_H
> >
> > #include <linux/kvm_host.h>
> > +#include <asm/fpu/xstate.h>
> > #include <asm/mce.h>
> > #include <asm/pvclock.h>
> > #include "kvm_cache_regs.h"
> > @@ -325,7 +326,22 @@ extern bool enable_pmu;
> > */
> > static inline u64 kvm_get_filtered_xcr0(void)
> > {
> > - return kvm_caps.supported_xcr0 & xstate_get_guest_group_perm();
> > + u64 supported_xcr0 = kvm_caps.supported_xcr0;
> > +
> > + BUILD_BUG_ON(XFEATURE_MASK_USER_DYNAMIC != XFEATURE_MASK_XTILE_DATA);
> > +
> > + if (supported_xcr0 & XFEATURE_MASK_USER_DYNAMIC) {
> > + supported_xcr0 &= xstate_get_guest_group_perm();
> > +
> > + /*
> > + * Treat XTILE_CFG as unsupported if the current process isn't
> > + * allowed to use XTILE_DATA, as attempting to set XTILE_CFG in
> > + * XCR0 without setting XTILE_DATA is architecturally illegal.
> > + */
> > + if (!(supported_xcr0 & XFEATURE_MASK_XTILE_DATA))
> > + supported_xcr0 &= XFEATURE_MASK_XTILE_CFG;
>
> should be this? supported_xcr0 &= ~XFEATURE_MASK_XTILE_CFG;
Doh, yes.
