Date:   Mon, 13 Dec 2021 13:29:30 -0800
From:   Luis Chamberlain <mcgrof@kernel.org>
To:     "Eric W. Biederman" <ebiederm@xmission.com>,
        Xiaoming Ni <nixiaoming@huawei.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk,
        keescook@chromium.org, jlayton@kernel.org, bfields@fieldses.org,
        yzaikin@google.com, wangle6@huawei.com,
        Joe Perches <joe@perches.com>
Subject: Re: [PATCH] sysctl: Add a group of macro functions to initcall the
 sysctl table of each feature
Message-ID: <Ybe7Ot8b/N4yy3TM@bombadil.infradead.org>
References: <20211207011320.100102-1-nixiaoming@huawei.com>
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 <Ya/BnndSXKHiUpGm@bombadil.infradead.org>
 <875ys0azt8.fsf@email.froward.int.ebiederm.org>
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On Mon, Dec 13, 2021 at 10:04:48AM -0600, Eric W. Biederman wrote:
> If you look at __register_sysctl_table the core registration function
> you will see that all directory entries get reduced to simply a path
> component.  So they have nothing but their names as input into
> the sysctl subsystem.
> 
> Further __register_sysctl_table goes in a loop through the path
> and does get_subdir to find or create the directory.
> 
> Which means that if two places were to register sysctls in
> the "fs" directory they would both use the safe "fs" directory
> and whoever can first would create it.
> 
> Which should mean that worrying about ordering is completely
> unnecessary.
> 
> What am I missing?

I was being too cautious, sorry for not having dug enough.
Then this makes things much easier. Thanks!

  Luis