On Fri, Sep 04, 2020 at 03:06:28PM -0600, Jens Axboe wrote:
> 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
Thanks for the backport, but this didn't apply at all to the 5.8.y tree.
What one did you make it against?
thanks,
greg k-h
