Merge tag 'io_uring-6.0-2022-09-29' of git://git.kernel.dk/linux

Pull io_uring fixes from Jens Axboe:
 "Two fixes that should go into 6.0:

   - Tweak the single issuer logic to register the task at creation,
     rather than at first submit. SINGLE_ISSUER was added for 6.0, and
     after some discussion on this, we decided to make it a bit stricter
     while it's still possible to do so (Dylan).

   - Stefan from Samba had some doubts on the level triggered poll that
     was added for this release. Rather than attempt to mess around with
     it now, just do the quick one-liner to disable it for release and
     we have time to discuss and change it for 6.1 instead (me)"

* tag 'io_uring-6.0-2022-09-29' of git://git.kernel.dk/linux:
  io_uring/poll: disable level triggered poll
  io_uring: register single issuer task at creation

Author: torvalds

io_uring/io_uring.c

@@ -3357,6 +3357,10 @@ static __cold int io_uring_create(unsigned entries, struct io_uring_params *p,
 		goto err;
 	}
 
+	if (ctx->flags & IORING_SETUP_SINGLE_ISSUER
+	    && !(ctx->flags & IORING_SETUP_R_DISABLED))
+		ctx->submitter_task = get_task_struct(current);
+
 	file = io_uring_get_file(ctx);
 	if (IS_ERR(file)) {
 		ret = PTR_ERR(file);
@@ -3548,6 +3552,9 @@ static int io_register_enable_rings(struct io_ring_ctx *ctx)
 	if (!(ctx->flags & IORING_SETUP_R_DISABLED))
 		return -EBADFD;
 
+	if (ctx->flags & IORING_SETUP_SINGLE_ISSUER && !ctx->submitter_task)
+		ctx->submitter_task = get_task_struct(current);
+
 	if (ctx->restrictions.registered)
 		ctx->restricted = 1;
 

io_uring/poll.c

@@ -857,7 +857,7 @@ int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 	if (sqe->buf_index || sqe->off || sqe->addr)
 		return -EINVAL;
 	flags = READ_ONCE(sqe->len);
-	if (flags & ~(IORING_POLL_ADD_MULTI|IORING_POLL_ADD_LEVEL))
+	if (flags & ~IORING_POLL_ADD_MULTI)
 		return -EINVAL;
 	if ((flags & IORING_POLL_ADD_MULTI) && (req->flags & REQ_F_CQE_SKIP))
 		return -EINVAL;