Re: [PATCH 04/10] block/rnbd-srv: no need to check sess_dev

[Jinpu Wang <jinpu.wang@xxxxxxxxx>]

On Tue, May 23, 2023 at 9:53 AM Guoqing Jiang <guoqing.jiang@xxxxxxxxx> wrote:
>
> Check ret is enough since if sess_dev is NULL which also
> implies ret should be 0.
>
> Signed-off-by: Guoqing Jiang <guoqing.jiang@xxxxxxxxx>
> ---
>  drivers/block/rnbd/rnbd-srv.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/block/rnbd/rnbd-srv.c b/drivers/block/rnbd/rnbd-srv.c
> index e9ef6bd4b50c..c4122e65b36a 100644
> --- a/drivers/block/rnbd/rnbd-srv.c
> +++ b/drivers/block/rnbd/rnbd-srv.c
> @@ -96,7 +96,7 @@ rnbd_get_sess_dev(int dev_id, struct rnbd_srv_session *srv_sess)
>                 ret = kref_get_unless_zero(&sess_dev->kref);
>         rcu_read_unlock();
>
> -       if (!sess_dev || !ret)
> +       if (!ret)
>                 return ERR_PTR(-ENXIO);
>
>         return sess_dev;
> --
> 2.35.3

This looks wrong, if you drop the check for !sess_dev, you have to
check it later with IS_ERR_OR_NULL when call rnbd_get_sess_dev