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Date:   Thu, 25 May 2023 10:12:19 +0200
From:   Simon Horman <simon.horman@corigine.com>
To:     Osama Muhammad <osmtendev@gmail.com>
Cc:     krzysztof.kozlowski@linaro.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, nbd@nbd.name, ryder.lee@mediatek.com,
        lorenzo@kernel.org, shayne.chen@mediatek.com, davem@davemloft.net,
        linux-wireless@vger.kernel.org, linux-mediatek@lists.infradead.org
Subject: Re: [PATCH] nfcsim.c: Fix error checking for debugfs_create_dir
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On Wed, May 24, 2023 at 08:55:06PM +0500, Osama Muhammad wrote:
> This patch fixes the error checking in nfcsim.c in
> debugfs_create_dir. The correct way to check if an error occurred
> is using 'IS_ERR' inline function.
> 
> Signed-off-by: Osama Muhammad <osmtendev@gmail.com>

...

On Wed, May 24, 2023 at 09:03:52PM +0500, Osama Muhammad wrote:
> This patch fixes the error checking in debugfs.c in
> debugfs_create_dir. The correct way to check if an error occurred
> is using 'IS_ERR' inline function.
> 
> Signed-off-by: Osama Muhammad <osmtendev@gmail.com>

...

The comment above debugfs_create_dir includes the following text.

 * NOTE: it's expected that most callers should _ignore_ the errors returned
 * by this function. Other debugfs functions handle the fact that the "dentry"
 * passed to them could be an error and they don't crash in that case.
 * Drivers should generally work fine even if debugfs fails to init anyway.

And I notice that in this same file there are calls to debugfs_create_dir()
where that advice is followed: the return value is ignored.

So I think the correct approaches here are to either:

1. Do nothing, the code isn't really broken
2. Remove the error checking

-- 
pw-bot: cr