linux-kernel - Re: [PATCH v1] drivers: edac: Drop unnecessary error check for debugfs_create

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Date:   Mon, 28 Aug 2023 19:05:47 +0530
From:   Atul Kumar Pant <atulpant.linux@...il.com>
To:     Michal Simek <michal.simek@....com>
Cc:     shubhrajyoti.datta@....com, sai.krishna.potthuri@....com,
        bp@...en8.de, tony.luck@...el.com, james.morse@....com,
        mchehab@...nel.org, rric@...nel.org, linux-edac@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        shuah@...nel.org
Subject: Re: [PATCH v1] drivers: edac: Drop unnecessary error check for
 debugfs_create_dir

On Fri, Aug 25, 2023 at 09:31:54AM +0200, Michal Simek wrote:
> 
> 
> On 8/15/23 22:38, Atul Kumar Pant wrote:
> > This patch removes the error checking for debugfs_create_dir.
> 
> Avoid using "This patch".

	Thanks for pointing this out. I'll remember this.

> 
> > Even if we get an error from this function, other debugfs APIs will
> > handle the error value and doesn't crash in that case. Hence caller can
> > safely ignore the errors that occur during the creation of debugfs nodes.
> 
> First of all which issue do you have? Did you see that folder is not created?

	I have not seen any issue as such. But going by the comments before
	the debugfs_create_dir API (https://elixir.bootlin.com/linux/latest/source/fs/debugfs/inode.c#L583),
	we can ignore safely ignore the return value from this API.

> 
> I am not quite sure if this is the right behavior.
> In the code there is
> 135         if (!parent)
> 136                 parent = edac_debugfs;
> 
> It means you are right that if creating ocm folder can fail and properties
> will be still created under edac_debugfs but is this the right behavior?
> 
> altera_edac/armada_xp_edac/i10nm/i5100/igen6/others are checking return
> value that's why I can't see any reason to remove this checking from one
> driver.
> 
> If you want to fix all please send patch for all but I don't think it will
> improve situation and it will just hide different issue if creating folder
> fails.

	Understood your point. Are you suggesting that we should keep these
	checks as it is, or should I fix for all the drivers and upload the
	patch ?

> And debugfs will be disabled in production system anyway.
> 
> Thanks,
> Michal
> 
> 
> 
>