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Subject: Re: Removing Mandatory Locks
From:   Jeff Layton <jlayton@kernel.org>
To:     "Eric W. Biederman" <ebiederm@xmission.com>,
        Matthew Wilcox <willy@infradead.org>
Cc:     Andy Lutomirski <luto@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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Date:   Thu, 19 Aug 2021 14:39:36 -0400
In-Reply-To: <87k0kkxbjn.fsf_-_@disp2133>
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         <87eeay8pqx.fsf@disp2133>
         <5b0d7c1e73ca43ef9ce6665fec6c4d7e@AcuMS.aculab.com>
         <87h7ft2j68.fsf@disp2133>
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On Tue, 2021-08-17 at 11:48 -0500, Eric W. Biederman wrote:
> Matthew Wilcox <willy@infradead.org> writes:
> 
> > On Fri, Aug 13, 2021 at 05:49:19PM -0700, Andy Lutomirski wrote:
> > > [0] we have mandatory locks, too. Sigh.
> > 
> > I'd love to remove that.  Perhaps we could try persuading more of the
> > distros to disable the CONFIG option first.
> 
> Yes.  The support is disabled in RHEL8.
> 
> Does anyone know the appropriate people to talk to encourage other
> distro's to encourage them to disable the CONFIG_MANDATORY_FILE_LOCKING?
> 
> Either that or we can wait until the code bit-rots, but distro's
> disabling and removing a feature on their own is the more responsible
> path.
> 
> Given how many hoops need to be jumped through to use mandatory file
> locking once it is enabled, and the fact it has never worked in
> containers makes me suspect there are no more users.
> 

I'm all for ripping it out too. It's an insane interface anyway.

I've not heard a single complaint about this being turned off in
fedora/rhel or any other distro that has this disabled.

Cheers,
-- 
Jeff Layton <jlayton@kernel.org>