From: Jens Axboe <axboe@kernel.dk>
Date: Sun, 20 Nov 2022 17:20:46 +0000 (-0700)
Subject: Revert "io_uring: disallow self-propelled ring polling"
X-Git-Tag: v6.2-rc1~131^2~20
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4061f0ef730cca5171351b7018b34a45b76df9c2;p=thirdparty%2Flinux.git

Revert "io_uring: disallow self-propelled ring polling"

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 03e02acda8e2)
and so can epoll (see details in caf1aeaffc3b). 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>
---

diff --git a/io_uring/poll.c b/io_uring/poll.c
index 22c9b2e0944a0..cd4d98d622d2f 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)) {