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Date: Fri, 5 Feb 2016 15:54:56 -0500
From: Tejun Heo <tj@kernel.org>
To: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>, Jiri Slaby <jslaby@suse.cz>,
        Thomas Gleixner <tglx@linutronix.de>, Petr Mladek <pmladek@suse.com>,
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        Sasha Levin <sasha.levin@oracle.com>, Shaohua Li <shli@fb.com>,
        LKML <linux-kernel@vger.kernel.org>, stable@vger.kernel.org,
        Daniel Bilik <daniel.bilik@neosystem.cz>
Subject: Re: Crashes with 874bbfe600a6 in 3.18.25
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Hello, Mike.

On Fri, Feb 05, 2016 at 09:47:11PM +0100, Mike Galbraith wrote:
> That very point is what makes it wrong for the workqueue code to ever
> target a work item.  The instant it does target selection, correctness
> may be at stake, it doesn't know, thus it must assume the full onus,
> which it has neither the knowledge not the time to do.  That's how we
> exploded on node = -1, trying to help out the user by doing his job,

I have a hard time seeing the NUMA_NO_NODE bug as something that
indicative of anything.  It is a dumb bug from mm side which puts
everyone using cpu_to_node() at risk.

> but then not doing the whole job.  IMHO, a better plan is to let the
> user screw it up all by himself.

What are you suggesting?

Thanks.

-- 
tejun