Re: [PATCH] KVM: x86: Fix load damaged SSEx MXCSR register

[Wanpeng Li]

2017-05-10 23:35 GMT+08:00 Paolo Bonzini <pbonzini@xxxxxxxxxx>:
>
>
> On 10/05/2017 12:19, Wanpeng Li wrote:
>>                * with old userspace.
>>                */
>> -             if (xstate_bv & ~kvm_supported_xcr0())
>> +             if (xstate_bv & ~kvm_supported_xcr0() ||
>> +                     mxcsr & ~vcpu->arch.guest_fpu.state.xsave.i387.mxcsr_mask)
>>                       return -EINVAL;
>>               load_xsave(vcpu, (u8 *)guest_xsave->region);
>>       } else {
>> -             if (xstate_bv & ~XFEATURE_MASK_FPSSE)
>> +             if (xstate_bv & ~XFEATURE_MASK_FPSSE ||
>> +                     mxcsr & ~vcpu->arch.guest_fpu.state.fxsave.mxcsr_mask)
>>                       return -EINVAL;
>>               memcpy(&vcpu->arch.guest_fpu.state.fxsave,
>>                       guest_xsave->region, sizeof(struct fxregs_state));
>
> Hmm, thinking more about it, maybe use mxcsr_feature_mask instead of
> digging into vcpu->arch.guest_fpu?  If you send v2, please remember to

ERROR: "mxcsr_feature_mask" [arch/x86/kvm/kvm.ko] undefined. So we
should dig into vcpu->arch.guest_fpu.

Regards,
Wanpeng Li