The patch below does not apply to the 5.11-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From b5b0ecb736f1ce1e68eb50613c0cfecff10198eb Mon Sep 17 00:00:00 2001

From: Jens Axboe axboe@kernel.dk Date: Thu, 4 Mar 2021 21:02:58 -0700 Subject: [PATCH] io_uring: clear IOCB_WAITQ for non -EIOCBQUEUED return

The callback can only be armed, if we get -EIOCBQUEUED returned. It's important that we clear the WAITQ bit for other cases, otherwise we can queue for async retry and filemap will assume that we're armed and return -EAGAIN instead of just blocking for the IO.

Cc: stable@vger.kernel.org # 5.9+ Signed-off-by: Jens Axboe axboe@kernel.dk

diff --git a/fs/io_uring.c b/fs/io_uring.c index 044170165402..5762750c666c 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -3286,6 +3286,7 @@ static int io_read(struct io_kiocb *req, unsigned int issue_flags) if (ret == -EIOCBQUEUED) return 0; /* we got some bytes, but not all. retry. */ + kiocb->ki_flags &= ~IOCB_WAITQ; } while (ret > 0 && ret < io_size); done: kiocb_done(kiocb, ret, issue_flags);