Re: [RFC PATCH v11 13/29] KVM: Add transparent hugepage support for dedicated guest memory

[Sean Christopherson]

On Fri, Jul 21, 2023, Paolo Bonzini wrote:
> On 7/19/23 01:44, Sean Christopherson wrote:
> > @@ -413,6 +454,9 @@ int kvm_gmem_create(struct kvm *kvm, struct kvm_create_guest_memfd *args)
> >   	u64 flags = args->flags;
> >   	u64 valid_flags = 0;
> > +	if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE))
> > +		valid_flags |= KVM_GUEST_MEMFD_ALLOW_HUGEPAGE;
> > +
> 
> I think it should be always allowed.  The outcome would just be "never have
> a hugepage" if thp is not enabled in the kernel.

I don't have a strong preference.  My thinking was that userspace would probably
rather have an explicit error, as opposed to silently running with a misconfigured
setup.