Re: [PATCH] KVM: x86: TDX: Use validated CPUID entry count for TD init

[Edgecombe, Rick P]

On Wed, 2026-07-08 at 17:04 +0800, Binbin Wu wrote:
> > Maybe it would be better to check for a mismatch and return -EINVAL?
> > 
> >  	if (init_vm->cpuid.nent != nr_user_entries) {
> >  		ret = -EINVAL;
> >  		goto out;
> >  	}
> > 
> > That would make the mismatch explicit instead of silently accepting an
> > inconsistent userspace snapshot.
> 
> I chose to use the snapshot value to follow KVM_SET_CPUID2's style.
> KVM_SET_CPUID2 kind of uses the snapshot value of entry count.
> 
> But returning a error code is OK for me.
> Let's wait and see what others prefer.

It does seem safer to reject input than have some implicit behavior.