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>
This commit is contained in:
Jens Axboe 2021-04-15 09:47:13 -06:00
parent c5de00366e
commit ea6a693d86

View file

@ -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;