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From:   "Eric W. Biederman" <ebiederm@xmission.com>
To:     Luis Chamberlain <mcgrof@kernel.org>
Cc:     Thomas =?utf-8?Q?Wei=C3=9Fschuh?= <linux@weissschuh.net>,
        Joel Granados <j.granados@samsung.com>,
        Kees Cook <keescook@chromium.org>,
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        linux-fsdevel@vger.kernel.org
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Date:   Wed, 13 Dec 2023 12:18:00 -0600
In-Reply-To: <ZXlhkJm2KjCymcqu@bombadil.infradead.org> (Luis Chamberlain's
        message of "Tue, 12 Dec 2023 23:47:28 -0800")
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Subject: Re: [PATCH v2 00/18] sysctl: constify sysctl ctl_tables
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Luis Chamberlain <mcgrof@kernel.org> writes:

> On Mon, Dec 11, 2023 at 12:25:10PM +0100, Thomas Weißschuh wrote:
>> Before sending it I'd like to get feedback on the internal rework of the
>> is_empty detection from you and/or Luis.
>> 
>> https://git.sr.ht/~t-8ch/linux/commit/ea27507070f3c47be6febebe451bbb88f6ea707e
>> or the attached patch.
>
> Please send as a new patch as RFC and please ensure on the To field is
> first "Eric W. Biederman" <ebiederm@xmission.com> with a bit more
> elaborate commit log as suggested from my review below. If there are
> any hidden things me and Joel could probably miss I'm sure Eric will
> be easily able to spot it.
>
>> From ea27507070f3c47be6febebe451bbb88f6ea707e Mon Sep 17 00:00:00 2001
>> From: =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= <linux@weissschuh.net>
>> Date: Sun, 3 Dec 2023 21:56:46 +0100
>> Subject: [PATCH] sysctl: move permanently empty flag to ctl_dir
>> MIME-Version: 1.0
>> Content-Type: text/plain; charset=UTF-8
>> Content-Transfer-Encoding: 8bit
>> 
>> Simplify the logic by always keeping the permanently_empty flag on the
>> ctl_dir.
>> The previous logic kept the flag in the leaf ctl_table and from there
>> transferred it to the ctl_table from the directory.
>> 
>> This also removes the need to have a mutable ctl_table and will allow
>> the constification of those structs.

> Please elaborate a bit more on this here in your next RFC.

> It's a pretty aggressive cleanup, specially with the new hipster guard()
> call but I'd love Eric's eyeballs on a proper v2.

I will look at a v2 time permitting.

My sense is that changing the locking probably make sense as a separate
patch.

Eric