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Date:   Thu, 31 Aug 2023 15:17:44 +0100
From:   "Russell King (Oracle)" <linux@armlinux.org.uk>
To:     Jinjie Ruan <ruanjinjie@huawei.com>
Cc:     gregory.greenman@intel.com, kvalo@kernel.org,
        briannorris@chromium.org, nbd@nbd.name, lorenzo@kernel.org,
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        nishants@marvell.com, linux-wireless@vger.kernel.org,
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Subject: Re: [PATCH net 0/3] wifi: Fix the NULL vs IS_ERR() bugs for
 debugfs_create_dir()
Message-ID: <ZPChCNLPMQiRrVU5@shell.armlinux.org.uk>
References: <20230831141347.3166988-1-ruanjinjie@huawei.com>
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Sender: Russell King (Oracle) <linux@armlinux.org.uk>
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On Thu, Aug 31, 2023 at 10:13:44PM +0800, Jinjie Ruan wrote:
> Since debugfs_create_dir() returns ERR_PTR and never return NULL, So use
> IS_ERR() to check it instead of checking NULL.

It is preferred that the return value from debugfs functions is _not_
checked.

See for example:

https://lore.kernel.org/linux-arm-kernel/20180601111004.1670-3-gregkh@linuxfoundation.org/T/

Thanks.

-- 
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