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Subject: Re: Removing Mandatory Locks
From:   Jeff Layton <jlayton@kernel.org>
To:     Rodrigo Campos <rodrigo@kinvolk.io>,
        "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     Matthew Wilcox <willy@infradead.org>,
        Andy Lutomirski <luto@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        David Laight <David.Laight@aculab.com>,
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Date:   Thu, 19 Aug 2021 15:18:15 -0400
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On Wed, 2021-08-18 at 11:34 +0200, Rodrigo Campos wrote:
> On Tue, Aug 17, 2021 at 6:49 PM Eric W. Biederman <ebiederm@xmission.com> 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.
> 
> If it helps, it seems to be enabled on the just released debian stable:
>     $ grep CONFIG_MANDATORY_FILE_LOCKING /boot/config-5.10.0-8-amd64
>     CONFIG_MANDATORY_FILE_LOCKING=y
> 
> Also the new 5.13 kernel in experimental has it too:
>     $ grep CONFIG_MANDATORY_FILE_LOCKING /boot/config-5.13.0-trunk-amd64
>     CONFIG_MANDATORY_FILE_LOCKING=y

A pity. It would have been nice if they had turned it off a while ago. I
guess I should have done more outreach at the time. Sigh...

In any case, I'm still inclined toward just ripping it out at this
point. It's hard to believe that anyone really uses it.
-- 
Jeff Layton <jlayton@kernel.org>