Re: [PATCH 3/3] remoteproc: core: Cleanup device in case of failure

From: Bjorn Andersson <bjorn.andersson@linaro.org>
To: Siddharth Gupta <sidgup@codeaurora.org>
Cc: ohad@wizery.com, linux-remoteproc@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org, psodagud@codeaurora.org,
	stable@vger.kernel.org
Subject: Re: [PATCH 3/3] remoteproc: core: Cleanup device in case of failure
Date: Thu, 27 May 2021 22:50:55 -0500	[thread overview]
Message-ID: <YLBon0bBnzrizpDi@builder.lan> (raw)
In-Reply-To: <1621284349-22752-4-git-send-email-sidgup@codeaurora.org>

On Mon 17 May 15:45 CDT 2021, Siddharth Gupta wrote:

> When a failure occurs in rproc_add() it returns an error, but does
> not cleanup after itself. This change adds the failure path in such
> cases.
> 
> Signed-off-by: Siddharth Gupta <sidgup@codeaurora.org>
> ---
>  drivers/remoteproc/remoteproc_core.c | 15 ++++++++++++---
>  1 file changed, 12 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index 45d09bf..6f5fa81 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -2326,8 +2326,10 @@ int rproc_add(struct rproc *rproc)
>  		return ret;
>  
>  	ret = device_add(dev);
> -	if (ret < 0)
> -		return ret;
> +	if (ret < 0) {
> +		put_device(dev);
> +		goto rproc_remove_cdev;
> +	}
>  
>  	dev_info(dev, "%s is available\n", rproc->name);
>  
> @@ -2338,7 +2340,7 @@ int rproc_add(struct rproc *rproc)
>  	if (rproc->auto_boot) {
>  		ret = rproc_trigger_auto_boot(rproc);
>  		if (ret < 0)
> -			return ret;
> +			goto rproc_remove_dev;
>  	}
>  
>  	/* expose to rproc_get_by_phandle users */
> @@ -2347,6 +2349,13 @@ int rproc_add(struct rproc *rproc)
>  	mutex_unlock(&rproc_list_mutex);
>  
>  	return 0;
> +
> +rproc_remove_dev:
> +	rproc_delete_debug_dir(rproc);
> +	device_del(dev);
> +rproc_remove_cdev:
> +	rproc_char_device_remove(rproc);

I'm confused, shouldn't this function just do cdev_del()?
__unregister_chrdev() seems to do more than unroll what cdev_add()
did...

Apart from this, I think the patch looks good. Really nice to see you
tidy this up!

Regards,
Bjorn

> +	return ret;
>  }
>  EXPORT_SYMBOL(rproc_add);
>  
> -- 
> Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
> 