Commit ea6a693d authored Apr 15, 2021 by Jens Axboe

io_uring: disable multishot poll for double poll add cases



The re-add handling isn't correct for the multi wait case, so let's
just disable it for now explicitly until we can get that sorted out. This
just turns it into a one-shot request. Since we pass back whether or not
a poll request terminates in multishot mode on completion, this should
not break properly behaving applications that check for IORING_CQE_F_MORE
on completion.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

parent c5de0036

fs/io_uring.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -4976,6 +4976,12 @@ static void __io_queue_proc(struct io_poll_iocb poll, struct io_poll_table pt,
		pt->error = -EINVAL;
		return;
		}
		/*
		* Can't handle multishot for double wait for now, turn it
		* into one-shot mode.
		*/
		if (!(req->poll.events & EPOLLONESHOT))
		req->poll.events \|= EPOLLONESHOT;
		/* double add on the same waitqueue head, ignore */
		if (poll->head == head)
		return;