On Fri, Jun 21, 2019 at 10:39:11AM -0300, Jason Gunthorpe wrote: > > Hmm, this function, and the other, goes on to do: > > if (unlikely(!access_ok((void __user *)start, len))) > return 0; > > and I thought that access_ok takes in the tagged pointer? > > How about re-order it a bit? The patch doesn't really work as-as an misses the main get_user_pages_fast fast path, but I'll add something equivalent.