On Fri, Feb 24, 2023, Aaron Lewis wrote: > Be a good citizen and don't allow any of the supported AMX xfeatures[1] > to be set if they can't all be set. That way userspace or a guest > doesn't fail if it attempts to set them in XCR0. > > [1] CPUID.(EAX=0DH,ECX=0):EAX.XTILE_CFG[bit-17] > CPUID.(EAX=0DH,ECX=0):EAX.XTILE_DATA[bit-18] > > Suggested-by: Sean Christopherson <seanjc@xxxxxxxxxx> > Signed-off-by: Aaron Lewis <aaronlewis@xxxxxxxxxx> Reviewed-by: Mingwei Zhang <mizhang@xxxxxxxxxx> > --- > arch/x86/kvm/cpuid.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c > index 1eff76f836a2..ac0423508b28 100644 > --- a/arch/x86/kvm/cpuid.c > +++ b/arch/x86/kvm/cpuid.c > @@ -72,6 +72,9 @@ static u64 sanitize_xcr0(u64 xcr0) > if ((xcr0 & mask) != mask) > xcr0 &= ~XFEATURE_MASK_AVX512; > > + if ((xcr0 & XFEATURE_MASK_XTILE) != XFEATURE_MASK_XTILE) > + xcr0 &= ~XFEATURE_MASK_XTILE; > + > return xcr0; > } > > -- > 2.39.2.637.g21b0678d19-goog >
