Re: KVM_SET_CPUID doesn't check supported bits (was Re: [PATCH 0/6] KVM: x86: KVM_SET_SREGS.CR4 bug fixes and cleanup)

[stsp]

07.12.2020 17:34, Paolo Bonzini пишет:
>     > It is too late to change that aspect of the API, unfortunately. We
>     > don't know how various userspaces would behave.
>     Which means some sensible behaviour
>     already exists if I don't call KVM_SET_CPUID2.
>     So what is it, #UD on CPUID?
>
>
> I would have to check but I think you always get zeroes; not entirely 
> sensible.
In that case I would argue that you can't
break anything by changing that to something
sensible. :)
But anyway, since my problem is solved,
this is just a potential improvement for the
future, or the case for documenting.