Re: [PATCH] remoteproc: imx_dsp_rproc: Improve exception handling in imx_dsp_rproc_mbox_alloc()

[Mathieu Poirier <mathieu.poirier@linaro.org>]

On Thu, Apr 06, 2023 at 10:12:50PM +0200, Markus Elfring wrote:
> Date: Thu, 6 Apr 2023 22:00:24 +0200
> 
> The label “err_out” was used to jump to another pointer check
> despite of the detail in the implementation of the function
> “imx_dsp_rproc_mbox_alloc” that it was determined already
> that the corresponding variable contained an error pointer
> because of a failed call of the function “mbox_request_channel_byname”.
> 
> Thus perform the following adjustments:
> 
> 1. Return directly after a call of the function
>    “mbox_request_channel_byname” failed for the input parameter “tx”.
> 
> 2. Use more appropriate labels instead.
> 
> 3. Reorder jump targets at the end.
> 
> 4. Omit a function call and three extra checks.
> 
> 
> This issue was detected by using the Coccinelle software.
> 
> Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
> ---
>  drivers/remoteproc/imx_dsp_rproc.c | 18 +++++++-----------
>  1 file changed, 7 insertions(+), 11 deletions(-)
>

Applied

Thanks,
Mathieu

> diff --git a/drivers/remoteproc/imx_dsp_rproc.c b/drivers/remoteproc/imx_dsp_rproc.c
> index 21759d9e5b7b..a8ad15ef1da0 100644
> --- a/drivers/remoteproc/imx_dsp_rproc.c
> +++ b/drivers/remoteproc/imx_dsp_rproc.c
> @@ -530,7 +530,7 @@ static int imx_dsp_rproc_mbox_alloc(struct imx_dsp_rproc *priv)
>  		ret = PTR_ERR(priv->tx_ch);
>  		dev_dbg(cl->dev, "failed to request tx mailbox channel: %d\n",
>  			ret);
> -		goto err_out;
> +		return ret;
>  	}
> 
>  	/* Channel for receiving message */
> @@ -539,7 +539,7 @@ static int imx_dsp_rproc_mbox_alloc(struct imx_dsp_rproc *priv)
>  		ret = PTR_ERR(priv->rx_ch);
>  		dev_dbg(cl->dev, "failed to request rx mailbox channel: %d\n",
>  			ret);
> -		goto err_out;
> +		goto free_channel_tx;
>  	}
> 
>  	cl = &priv->cl_rxdb;
> @@ -555,19 +555,15 @@ static int imx_dsp_rproc_mbox_alloc(struct imx_dsp_rproc *priv)
>  		ret = PTR_ERR(priv->rxdb_ch);
>  		dev_dbg(cl->dev, "failed to request mbox chan rxdb, ret %d\n",
>  			ret);
> -		goto err_out;
> +		goto free_channel_rx;
>  	}
> 
>  	return 0;
> 
> -err_out:
> -	if (!IS_ERR(priv->tx_ch))
> -		mbox_free_channel(priv->tx_ch);
> -	if (!IS_ERR(priv->rx_ch))
> -		mbox_free_channel(priv->rx_ch);
> -	if (!IS_ERR(priv->rxdb_ch))
> -		mbox_free_channel(priv->rxdb_ch);
> -
> +free_channel_rx:
> +	mbox_free_channel(priv->rx_ch);
> +free_channel_tx:
> +	mbox_free_channel(priv->tx_ch);
>  	return ret;
>  }
> 
> --
> 2.40.0
>