Subject: Re: [PATCH 1/17] net/rds: Add missing mutex_unlock

From: Andy Grover <[email-masked]>
Date: Wed, 26 May 2010 10:55:02 -0700

Reviewed-by: Zach Brown <[email-masked]>
Acked-by: Andy Grover <[email-masked]>

-- Andy

On 05/26/2010 08:54 AM, Julia Lawall wrote:
> From: Julia Lawall<[email-masked]>
>
> Add a mutex_unlock missing on the error path.  In each case, whenever the
> label out is reached from elsewhere in the function, mutex is not locked.
>
> The semantic match that finds this problem is as follows:
> (http://coccinelle.lip6.fr/)
>
> //<smpl>
> @@
> expression E1;
> @@
>
> * mutex_lock(E1);
>    <+... when != E1
>    if (...) {
>      ... when != E1
> *   return ...;
>    }
>    ...+>
> * mutex_unlock(E1);
> //</smpl>
>
> Signed-off-by: Julia Lawall<[email-masked]>
>
> ---
>   net/rds/ib_cm.c |    1 +
>   net/rds/iw_cm.c |    1 +
>   2 files changed, 2 insertions(+)
>
> diff --git a/net/rds/ib_cm.c b/net/rds/ib_cm.c
> index 10ed0d5..f688327 100644
> --- a/net/rds/ib_cm.c
> +++ b/net/rds/ib_cm.c
> @@ -475,6 +475,7 @@ int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
>   	err = rds_ib_setup_qp(conn);
>   	if (err) {
>   		rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", err);
> +		mutex_unlock(&conn->c_cm_lock);
>   		goto out;
>   	}
>
> diff --git a/net/rds/iw_cm.c b/net/rds/iw_cm.c
> index a9d951b..b5dd6ac 100644
> --- a/net/rds/iw_cm.c
> +++ b/net/rds/iw_cm.c
> @@ -452,6 +452,7 @@ int rds_iw_cm_handle_connect(struct rdma_cm_id *cm_id,
>   	err = rds_iw_setup_qp(conn);
>   	if (err) {
>   		rds_iw_conn_error(conn, "rds_iw_setup_qp failed (%d)\n", err);
> +		mutex_unlock(&conn->c_cm_lock);
>   		goto out;
>   	}
>