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Date:   Mon, 3 Dec 2018 13:38:57 +0100
From:   Michal Hocko <mhocko@kernel.org>
To:     Oleg Nesterov <oleg@redhat.com>
Cc:     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>,
        Chanho Min <chanho.min@lge.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Pavel Machek <pavel@ucw.cz>
Subject: Re: [PATCH] Revert "exec: make de_thread() freezable (was: Re: Linux
 4.20-rc4)
Message-ID: <20181203123857.GS31738@dhcp22.suse.cz>
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On Mon 03-12-18 13:31:49, Oleg Nesterov wrote:
> On 12/03, Michal Hocko wrote:
> >
> > Now, I wouldn't mind to revert this because the code is really old and
> > we haven't seen many bug reports about failing suspend yet. But what is
> > the actual plan to make this work properly?
> 
> I don't see a simple solution...
> 
> But we need to fix exec/de_thread anyway, then we can probably reconsider
> this patch.

My concern is that de_thread fix might be too disruptive for stable
kernels while we might want to have a simple enough fix for the the
suspend issue in the meantime. That was actually the primary reason I've
acked the hack even though I didn't like it.

So can we find a way to shut the lockdep up when this is not really a
deadlock?  Or maybe this really is one and then we need a real fix for
stable as well.
-- 
Michal Hocko
SUSE Labs