> > +#include "kvm_util.h"
> > +#include "processor.h"
> > +
> > +#define XFEATURE_MASK_SSE (1ul << 1)
> > +#define XFEATURE_MASK_YMM (1ul << 2)
> > +#define XFEATURE_MASK_BNDREGS (1ul << 3)
> > +#define XFEATURE_MASK_BNDCSR (1ul << 4)
> > +#define XFEATURE_MASK_OPMASK (1ul << 5)
> > +#define XFEATURE_MASK_ZMM_Hi256 (1ul << 6)
> > +#define XFEATURE_MASK_Hi16_ZMM (1ul << 7)
> > +#define XFEATURE_MASK_XTILECFG (1ul << 17)
> > +#define XFEATURE_MASK_XTILEDATA (1ul << 18)
> > +#define XFEATURE_MASK_XTILE (XFEATURE_MASK_XTILECFG | \
> > + XFEATURE_MASK_XTILEDATA)
>
> With XSETBV hoisted into processor.h, shouldn't these macros be more
> widely available as well?
Sure, I'll hoist them up there too.
>
> > +static uint64_t get_supported_user_xfeatures(void)
> > +{
> > + uint32_t a, b, c, d;
> > +
> > + cpuid(0xd, &a, &b, &c, &d);
> > +
> > + return a | ((uint64_t)d << 32);
> > +}
> > +
> > + GUEST_ASSERT(xcr0_rest == 1ul);
> > +
> > + /* Check AVX */
> > + xfeature_mask = XFEATURE_MASK_SSE | XFEATURE_MASK_YMM;
> > + supported_state = supported_xcr0 & xfeature_mask;
> > + GUEST_ASSERT(supported_state != XFEATURE_MASK_YMM);
> > +
> > + /* Check MPX */
> > + xfeature_mask = XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR;
> > + supported_state = supported_xcr0 & xfeature_mask;
> > + GUEST_ASSERT((supported_state == xfeature_mask) ||
> > + (supported_state == 0ul));
> > +
> > + /* Check AVX-512 */
> > + xfeature_mask = XFEATURE_MASK_OPMASK |
> > + XFEATURE_MASK_ZMM_Hi256 |
> > + XFEATURE_MASK_Hi16_ZMM;
> > + supported_state = supported_xcr0 & xfeature_mask;
> > + GUEST_ASSERT((supported_state == xfeature_mask) ||
> > + (supported_state == 0ul));
> > +
> > + /* Check AMX */
> > + xfeature_mask = XFEATURE_MASK_XTILE;
> > + supported_state = supported_xcr0 & xfeature_mask;
> > + GUEST_ASSERT((supported_state == xfeature_mask) ||
> > + (supported_state == 0ul));
>
> In this series, you've added code to __do_cpuid_func() to ensure that
> XFEATURE_MASK_XTILECFG and XFEATURE_MASK_XTILEDATA can't be set unless
> the other is set. Do we need to do something similar for AVX-512 and
> MPX?
That does sound like a natural extension of this. I can add support
for that in v2.
>
> > + GUEST_SYNC(0);
> > +
> > + xsetbv(0, supported_xcr0);
> > +
> > + GUEST_DONE();
> > +}
> > +
> > +static void guest_gp_handler(struct ex_regs *regs)
> > +{
> > + GUEST_ASSERT(!"Failed to set the supported xfeature bits in XCR0.");
> > +}
> > +
