Hi,
Linus just pulled 3 fixes from me - 1+2 should apply directly, here's
the 3rd one which will need some love for 5.8-stable. I'm including it
below to preempt the failed to apply message :-)
commit fb8d4046d50f77a26570101e5b8a7a026320a610
Author: Jens Axboe <axboe@xxxxxxxxx>
Date: Wed Sep 2 10:19:04 2020 -0600
io_uring: no read/write-retry on -EAGAIN error and O_NONBLOCK marked file
Actually two things that need fixing up here:
- The io_rw_reissue() -EAGAIN retry is explicit to block devices and
regular files, so don't ever attempt to do that on other types of
files.
- If we hit -EAGAIN on a nonblock marked file, don't arm poll handler for
it. It should just complete with -EAGAIN.
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: Norman Maurer <norman.maurer@xxxxxxxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 82e15020d9a8..96be21ace79a 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2726,6 +2726,12 @@ static int io_read(struct io_kiocb *req, bool force_nonblock)
ret = ret2;
goto done;
}
+ /* no retry on NONBLOCK marked file */
+ if (req->file->f_flags & O_NONBLOCK) {
+ ret = ret2;
+ goto done;
+ }
+
/* some cases will consume bytes even on error returns */
iov_iter_revert(iter, iov_count - iov_iter_count(iter));
ret2 = 0;
@@ -2869,9 +2875,15 @@ static int io_write(struct io_kiocb *req, bool force_nonblock)
*/
if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT))
ret2 = -EAGAIN;
+ /* no retry on NONBLOCK marked file */
+ if (ret2 == -EAGAIN && (req->file->f_flags & O_NONBLOCK)) {
+ ret = 0;
+ goto done;
+ }
if (!force_nonblock || ret2 != -EAGAIN) {
if ((req->ctx->flags & IORING_SETUP_IOPOLL) && ret2 == -EAGAIN)
goto copy_iov;
+done:
kiocb_done(kiocb, ret2);
} else {
copy_iov:
--
Jens Axboe
