Re: [PATCH v4] remoteproc: k3-dsp: Fix an error handling path in k3_dsp_rproc_probe()

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

Andrew, Hari and Beleswar - please test this on your side and get back to me
with the results.

Thanks,
Mathieu

On Fri, Jun 27, 2025 at 11:42:33PM +0200, Christophe JAILLET wrote:
> IF an error occurs after a successful k3_rproc_request_mbox() call,
> mbox_free_channel() should be called to avoid a leak.
> 
> Such a call is missing in the error handing path of k3_dsp_rproc_probe().
> It is also missing both in the error handling path of k3_m4_rproc_probe()
> and in (in-existent) corresponding remove function.
> 
> Switch to managed resources to avoid these leaks and simplify the code.
> 
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> ---
> Compile tested only.
> 
> This is an update of [1].
> The code has been heavily refactored recently with things moved to
> ti_k3_common.c
> 
> This new version also fixes a leak in k3_m4_rproc_probe(). In this file,
> mbox_free_channel() was missing.
> 
> Being very different from the v3, I've removed the previous review tags.
> 
> [1]: https://lore.kernel.org/all/591e219df99da6f02c9d402f7854bc3ab23e76f9.1726328417.git.christophe.jaillet@wanadoo.fr/
> ---
>  drivers/remoteproc/ti_k3_common.c         | 12 +++++++++++-
>  drivers/remoteproc/ti_k3_dsp_remoteproc.c |  2 --
>  drivers/remoteproc/ti_k3_r5_remoteproc.c  |  2 --
>  3 files changed, 11 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/remoteproc/ti_k3_common.c b/drivers/remoteproc/ti_k3_common.c
> index d4f20900f33b..7a9c3fb80fec 100644
> --- a/drivers/remoteproc/ti_k3_common.c
> +++ b/drivers/remoteproc/ti_k3_common.c
> @@ -155,6 +155,13 @@ int k3_rproc_release(struct k3_rproc *kproc)
>  }
>  EXPORT_SYMBOL_GPL(k3_rproc_release);
>  
> +static void k3_rproc_free_channel(void *data)
> +{
> +	struct k3_rproc *kproc = data;
> +
> +	mbox_free_channel(kproc->mbox);
> +}
> +
>  int k3_rproc_request_mbox(struct rproc *rproc)
>  {
>  	struct k3_rproc *kproc = rproc->priv;
> @@ -173,6 +180,10 @@ int k3_rproc_request_mbox(struct rproc *rproc)
>  		return dev_err_probe(dev, PTR_ERR(kproc->mbox),
>  				     "mbox_request_channel failed\n");
>  
> +	ret = devm_add_action_or_reset(dev, k3_rproc_free_channel, kproc);
> +	if (ret)
> +		return ret;
> +
>  	/*
>  	 * Ping the remote processor, this is only for sanity-sake for now;
>  	 * there is no functional effect whatsoever.
> @@ -183,7 +194,6 @@ int k3_rproc_request_mbox(struct rproc *rproc)
>  	ret = mbox_send_message(kproc->mbox, (void *)RP_MBOX_ECHO_REQUEST);
>  	if (ret < 0) {
>  		dev_err(dev, "mbox_send_message failed (%pe)\n", ERR_PTR(ret));
> -		mbox_free_channel(kproc->mbox);
>  		return ret;
>  	}
>  
> diff --git a/drivers/remoteproc/ti_k3_dsp_remoteproc.c b/drivers/remoteproc/ti_k3_dsp_remoteproc.c
> index 7a72933bd403..d6ceea6dc920 100644
> --- a/drivers/remoteproc/ti_k3_dsp_remoteproc.c
> +++ b/drivers/remoteproc/ti_k3_dsp_remoteproc.c
> @@ -175,8 +175,6 @@ static void k3_dsp_rproc_remove(struct platform_device *pdev)
>  		if (ret)
>  			dev_err(dev, "failed to detach proc (%pe)\n", ERR_PTR(ret));
>  	}
> -
> -	mbox_free_channel(kproc->mbox);
>  }
>  
>  static const struct k3_rproc_mem_data c66_mems[] = {
> diff --git a/drivers/remoteproc/ti_k3_r5_remoteproc.c b/drivers/remoteproc/ti_k3_r5_remoteproc.c
> index ca5ff280d2dc..04f23295ffc1 100644
> --- a/drivers/remoteproc/ti_k3_r5_remoteproc.c
> +++ b/drivers/remoteproc/ti_k3_r5_remoteproc.c
> @@ -1206,8 +1206,6 @@ static void k3_r5_cluster_rproc_exit(void *data)
>  				return;
>  			}
>  		}
> -
> -		mbox_free_channel(kproc->mbox);
>  	}
>  }
>  
> -- 
> 2.50.0
>