* Re: [PATCH] block: clear iocb->private in blkdev_bio_end_io_async()
2022-02-11 9:01 [PATCH] block: clear iocb->private in blkdev_bio_end_io_async() Stefano Garzarella
@ 2022-02-21 11:49 ` Stefano Garzarella
2022-02-22 1:43 ` Ming Lei
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Stefano Garzarella @ 2022-02-21 11:49 UTC (permalink / raw)
To: Jens Axboe, Pavel Begunkov; +Cc: kernel list, linux-block
Gentle ping :-)
On Fri, Feb 11, 2022 at 10:01 AM Stefano Garzarella <sgarzare@redhat.com> wrote:
>
> iocb_bio_iopoll() expects iocb->private to be cleared before
> releasing the bio.
>
> We already do this in blkdev_bio_end_io(), but we forgot in the
> recently added blkdev_bio_end_io_async().
>
> Fixes: 54a88eb838d3 ("block: add single bio async direct IO helper")
> Cc: asml.silence@gmail.com
> Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
> ---
> I haven't seen a failure, I was just reading the code to understand iopoll,
> so IIUC we should clean iocb->private in blkdev_bio_end_io_async().
>
> Thanks,
> Stefano
> ---
> block/fops.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/block/fops.c b/block/fops.c
> index 4f59e0f5bf30..a18e7fbd97b8 100644
> --- a/block/fops.c
> +++ b/block/fops.c
> @@ -289,6 +289,8 @@ static void blkdev_bio_end_io_async(struct bio *bio)
> struct kiocb *iocb = dio->iocb;
> ssize_t ret;
>
> + WRITE_ONCE(iocb->private, NULL);
> +
> if (likely(!bio->bi_status)) {
> ret = dio->size;
> iocb->ki_pos += ret;
> --
> 2.34.1
>
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH] block: clear iocb->private in blkdev_bio_end_io_async()
2022-02-11 9:01 [PATCH] block: clear iocb->private in blkdev_bio_end_io_async() Stefano Garzarella
2022-02-21 11:49 ` Stefano Garzarella
@ 2022-02-22 1:43 ` Ming Lei
2022-02-22 8:21 ` Christoph Hellwig
2022-02-22 14:00 ` Jens Axboe
3 siblings, 0 replies; 5+ messages in thread
From: Ming Lei @ 2022-02-22 1:43 UTC (permalink / raw)
To: Stefano Garzarella; +Cc: Jens Axboe, linux-kernel, Pavel Begunkov, linux-block
On Fri, Feb 11, 2022 at 10:01:36AM +0100, Stefano Garzarella wrote:
> iocb_bio_iopoll() expects iocb->private to be cleared before
> releasing the bio.
>
> We already do this in blkdev_bio_end_io(), but we forgot in the
But also iomap_dio_bio_end_io().
> recently added blkdev_bio_end_io_async().
>
> Fixes: 54a88eb838d3 ("block: add single bio async direct IO helper")
> Cc: asml.silence@gmail.com
> Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
> ---
> I haven't seen a failure, I was just reading the code to understand iopoll,
> so IIUC we should clean iocb->private in blkdev_bio_end_io_async().
>
> Thanks,
> Stefano
> ---
> block/fops.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/block/fops.c b/block/fops.c
> index 4f59e0f5bf30..a18e7fbd97b8 100644
> --- a/block/fops.c
> +++ b/block/fops.c
> @@ -289,6 +289,8 @@ static void blkdev_bio_end_io_async(struct bio *bio)
> struct kiocb *iocb = dio->iocb;
> ssize_t ret;
>
> + WRITE_ONCE(iocb->private, NULL);
It might cause race in case of concurrent polling on same queue without
clearing iocb->private, so looks fine:
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Thanks,
Ming
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH] block: clear iocb->private in blkdev_bio_end_io_async()
2022-02-11 9:01 [PATCH] block: clear iocb->private in blkdev_bio_end_io_async() Stefano Garzarella
2022-02-21 11:49 ` Stefano Garzarella
2022-02-22 1:43 ` Ming Lei
@ 2022-02-22 8:21 ` Christoph Hellwig
2022-02-22 14:00 ` Jens Axboe
3 siblings, 0 replies; 5+ messages in thread
From: Christoph Hellwig @ 2022-02-22 8:21 UTC (permalink / raw)
To: Stefano Garzarella; +Cc: Jens Axboe, linux-kernel, Pavel Begunkov, linux-block
Looks good,
Reviewed-by: Christoph Hellwig <hch@lst.de>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] block: clear iocb->private in blkdev_bio_end_io_async()
2022-02-11 9:01 [PATCH] block: clear iocb->private in blkdev_bio_end_io_async() Stefano Garzarella
` (2 preceding siblings ...)
2022-02-22 8:21 ` Christoph Hellwig
@ 2022-02-22 14:00 ` Jens Axboe
3 siblings, 0 replies; 5+ messages in thread
From: Jens Axboe @ 2022-02-22 14:00 UTC (permalink / raw)
To: Stefano Garzarella; +Cc: Pavel Begunkov, linux-kernel, linux-block
On Fri, 11 Feb 2022 10:01:36 +0100, Stefano Garzarella wrote:
> iocb_bio_iopoll() expects iocb->private to be cleared before
> releasing the bio.
>
> We already do this in blkdev_bio_end_io(), but we forgot in the
> recently added blkdev_bio_end_io_async().
>
>
> [...]
Applied, thanks!
[1/1] block: clear iocb->private in blkdev_bio_end_io_async()
commit: bb49c6fa8b845591b317b0d7afea4ae60ec7f3aa
Best regards,
--
Jens Axboe
^ permalink raw reply [flat|nested] 5+ messages in thread