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Date:   Thu, 6 Dec 2018 09:57:49 +0100
From:   Pavel Machek <pavel@ucw.cz>
To:     Chanho Min <chanho.min@lge.com>
Cc:     'Oleg Nesterov' <oleg@redhat.com>,
        'Ingo Molnar' <mingo@kernel.org>,
        'Linus Torvalds' <torvalds@linux-foundation.org>,
        'Linux List Kernel Mailing' <linux-kernel@vger.kernel.org>,
        "'Rafael J. Wysocki'" <rafael.j.wysocki@intel.com>,
        'Thomas Gleixner' <tglx@linutronix.de>,
        'Peter Zijlstra' <a.p.zijlstra@chello.nl>,
        'Michal Hocko' <mhocko@suse.com>, seungho1.park@lge.com
Subject: Re: [PATCH] Revert "exec: make de_thread() freezable (was: Re: Linux
 4.20-rc4)
Message-ID: <20181206085748.GA16059@amd>
References: <CAHk-=wgdsXyCaLsFEpyUpAeRqVS69u=xo4rzEN+cS=xwz2gajg@mail.gmail.com>
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 <20181203115601.GA31795@redhat.com>
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Hi!

> > On 12/04, Ingo Molnar wrote:
> > >
> > > * Oleg Nesterov <oleg@redhat.com> wrote:
> > >
> > > > we really need to narrow the (huge) scope of ->cred_guard_mutex in =
exec
> > paths.
> > > >
> > > > my attempt to fix this was nacked, and nobody suggested a better so=
lution
> > so far.
> > >
> > > Any link to your patch and the NAK?
> >=20
> > See https://lore.kernel.org/lkml/20170213141452.GA30203@redhat.com/
> >=20
> > No questions, the patch wasn't pretty. And imo we need to rework the se=
curity
> > hooks in the long term.
> >=20
> > Oleg.
>=20
> I am sorry for the reverting this patch. It's also my fault that
> I didn't check lockdep. But, We decided to keep this patch in our product.
> Freeze fail is a real problem we've had for the last two years,
> whereas lockdep's notice is not a real problem.
> We hope this issue will be resolved soon.

I guess it makes sense for your usage.

How often do you see the failures without the patch?
									Pavel
--=20
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo=
g.html

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