[PATCH 4/4] Revert "io_uring: disallow self-propelled ring polling"

[Jens Axboe <axboe@kernel.dk>]

This reverts commit 7fdbc5f014c3f71bc44673a2d6c5bb2d12d45f25.

This patch dealt with a subset of the real problem, which is a potential
circular dependency on the wakup path for io_uring itself. Outside of
io_uring, eventfd can also trigger this (see details in 8c881e87feae)
and so can epoll (see details in 426930308abf). Now that we have a
generic solution to this problem, get rid of the io_uring specific
work-around.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 io_uring/poll.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/io_uring/poll.c b/io_uring/poll.c
index b5d9426c60f6..5733ed334738 100644
--- a/io_uring/poll.c
+++ b/io_uring/poll.c
@@ -246,8 +246,6 @@ static int io_poll_check_events(struct io_kiocb *req, bool *locked)
 			continue;
 		if (req->apoll_events & EPOLLONESHOT)
 			return IOU_POLL_DONE;
-		if (io_is_uring_fops(req->file))
-			return IOU_POLL_DONE;
 
 		/* multishot, just fill a CQE and proceed */
 		if (!(req->flags & REQ_F_APOLL_MULTISHOT)) {
-- 
2.35.1