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Date:   Wed, 10 Jul 2019 07:56:28 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Xiaoming Ni <nixiaoming@huawei.com>
Cc:     adobriyan@gmail.com, akpm@linux-foundation.org,
        anna.schumaker@netapp.com, arjan@linux.intel.com,
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Subject: Re: [PATCH v3 0/3] kernel/notifier.c: avoid duplicate registration
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On Wed, Jul 10, 2019 at 11:09:07AM +0800, Xiaoming Ni wrote:
> Registering the same notifier to a hook repeatedly can cause the hook
> list to form a ring or lose other members of the list.

Then don't do that :)

Is there any in-kernel users that do do this?  If so, please just fix
them.

thanks,

greg k-h