On Mon, Jul 30, 2018 at 09:15:43AM +0200, Christoph Hellwig wrote: > + apt.error = -EINVAL; /* same as no support for IOCB_CMD_POLL */ > + mask = vfs_poll(req->file, &apt.pt) & req->events; > + if (mask || apt.error) { > + bool removed = false; > + > + /* we did not manage to set up a waitqueue, done */ > + if (unlikely(!req->head)) > + goto out_fput; > +out_fput: > + fput(req->file); > + return apt.error; Ugh... So anything that simply returns a constant value, without even bothering to do poll_wait() (on the theory that no matter how much you wait, nothing will change) is going to git -EINVAL? What am I missing here?