KVM's own accesses to guest memory (i.e., places where it does copy_to/from_user) will go through GUP. By default, that's just how it would work. What I'm saying is that we aren't going to add anything extra to have "KVM Userfault" prevent KVM from doing a copy_to/from_user (like how I had it in the RFC, where KVM Userfault can block the translation of gfn -> hva). vhost's accesses to guest memory will be the same as KVM's: it will go through copy_to/from_user. Hopefully that's a little clearer. :)
