io_uring: short circuit -EAGAIN for blocking read attempt (f91daf56) · Commits · 戴 / test

One case was missed in the short IO retry handling, and that's hitting -EAGAIN on a blocking attempt read (eg from io-wq context). This is a problem on sockets that are marked as non-blocking when created, they don't carry any REQ_F_NOWAIT information to help us terminate them instead of perpetually retrying. Fixes: ("io_uring: internally retry short reads") Signed-off-by:

Jens Axboe <axboe@kernel.dk>

fs/io_uring.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -3186,6 +3186,8 @@ static int io_read(struct io_kiocb *req, bool force_nonblock,
		ret = 0;
		goto out_free;
		} else if (ret == -EAGAIN) {
		if (!force_nonblock)
		goto done;
		ret = io_setup_async_rw(req, iovec, inline_vecs, iter, false);
		if (ret)
		goto out_free;
		@@ -3195,7 +3197,8 @@ static int io_read(struct io_kiocb *req, bool force_nonblock,
		}

		/* read it all, or we did blocking attempt. no retry. */
		if (!iov_iter_count(iter) \|\| !force_nonblock)
		if (!iov_iter_count(iter) \|\| !force_nonblock \|\|
		(req->file->f_flags & O_NONBLOCK))
		goto done;

		io_size -= ret;

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