linux-kernel - Re: [PATCH v2] soc: mediatek: Simplify with dev_err

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <d269df37-3bf9-45fd-8e3f-fb4f36ff9d8f@notapiano>
Date: Fri, 30 Aug 2024 15:32:56 -0400
From: Nícolas F. R. A. Prado <nfraprado@...labora.com>
To: Yan Zhen <yanzhen@...o.com>
Cc: matthias.bgg@...il.com, angelogioacchino.delregno@...labora.com,
	linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
	linux-mediatek@...ts.infradead.org, opensource.kernel@...o.com
Subject: Re: [PATCH v2] soc: mediatek: Simplify with dev_err_probe()

Hi,

thank you for the patch. See comments below.

On Fri, Aug 30, 2024 at 04:05:38PM +0800, Yan Zhen wrote:
> Using dev_err_probe() to simplify the error path and unify a 
> message template.
> 

>From [1]:

  Describe your changes in imperative mood, e.g. “make xyzzy do frotz” instead of
  “[This patch] makes xyzzy do frotz” or “[I] changed xyzzy to do frotz”, as if
  you are giving orders to the codebase to change its behaviour.

[1] https://www.kernel.org/doc/html/latest/process/submitting-patches.html#describe-your-changes

So should be "Use dev_err_probe()...".

Also, the commit summary seems a bit too broad, please add "mtk-mmsys:" in the
subsystem:

  soc: mediatek: mtk-mmsys: Simplify with dev_err_probe()

> Using this helper is totally fine even if err is known to never
> be -EPROBE_DEFER.
> 
> The benefit compared to a normal dev_err() is the standardized format
> of the error code, it being emitted symbolically and the fact that
> the error code is returned which allows more compact error paths.
> 
> Signed-off-by: Yan Zhen <yanzhen@...o.com>
> ---
> 
> Changes in v2:
> - Get rid of `ret = PTR_ERR(mmsys->regs);`.
> 
>  drivers/soc/mediatek/mtk-mmsys.c | 15 ++++++---------
>  1 file changed, 6 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/soc/mediatek/mtk-mmsys.c b/drivers/soc/mediatek/mtk-mmsys.c
> index 938240714e54..a6e0c41c10ab 100644
> --- a/drivers/soc/mediatek/mtk-mmsys.c
> +++ b/drivers/soc/mediatek/mtk-mmsys.c
> @@ -397,11 +397,9 @@ static int mtk_mmsys_probe(struct platform_device *pdev)
>  		return -ENOMEM;
>  
>  	mmsys->regs = devm_platform_ioremap_resource(pdev, 0);
> -	if (IS_ERR(mmsys->regs)) {
> -		ret = PTR_ERR(mmsys->regs);
> -		dev_err(dev, "Failed to ioremap mmsys registers: %d\n", ret);
> -		return ret;
> -	}
> +	if (IS_ERR(mmsys->regs))
> +		return dev_err_probe(dev, PTR_ERR(mmsys->regs),
> +					"Failed to ioremap mmsys registers");

You're missing the \n at the end of the string.

Also, would look nicer if it was aligned like so:

		return dev_err_probe(dev, PTR_ERR(mmsys->regs),
				     "Failed to ioremap mmsys registers\n");

>  
>  	mmsys->data = of_device_get_match_data(&pdev->dev);
>  
> @@ -413,10 +411,9 @@ static int mtk_mmsys_probe(struct platform_device *pdev)
>  		mmsys->rcdev.ops = &mtk_mmsys_reset_ops;
>  		mmsys->rcdev.of_node = pdev->dev.of_node;
>  		ret = devm_reset_controller_register(&pdev->dev, &mmsys->rcdev);
> -		if (ret) {
> -			dev_err(&pdev->dev, "Couldn't register mmsys reset controller: %d\n", ret);
> -			return ret;
> -		}
> +		if (ret)
> +			dev_err_probe(&pdev->dev, ret,
> +					"Couldn't register mmsys reset controller");

You're missing the return here. And the \n is also missing.

Also, here checkpatch actually complains about the alignment (run
'scripts/checkpatch.pl --strict' on your patch).

CHECK: Alignment should match open parenthesis
#50: FILE: drivers/soc/mediatek/mtk-mmsys.c:416:
+			dev_err_probe(&pdev->dev, ret,
+					"Couldn't register mmsys reset controller");

After making those changes you can add

Reviewed-by: Nícolas F. R. A. Prado <nfraprado@...labora.com>

Thanks,
Nícolas