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Date: Mon, 21 Dec 2015 15:14:18 -0600 (CST)
From: Christoph Lameter <cl@linux.com>
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To: Sasha Levin <sasha.levin@oracle.com>
cc: Michal Hocko <mhocko@suse.cz>, LKML <linux-kernel@vger.kernel.org>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>
Subject: Re: mm, vmstat: kernel BUG at mm/vmstat.c:1408!
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On Mon, 21 Dec 2015, Sasha Levin wrote:

> I've also noticed a new warning from the workqueue code which my scripts
> didn't pick up before:
>
> [ 3462.380681] BUG: workqueue lockup - pool cpus=2 node=2 flags=0x4 nice=0 stuck for 54s!
> [ 3462.522041] workqueue vmstat: flags=0xc
> [ 3462.527795]   pwq 4: cpus=2 node=2 flags=0x0 nice=0 active=1/256
> [ 3462.554836]     pending: vmstat_update

Does that mean that vmstat_update locks up or something that schedules it?

Also what workload triggers the BUG()?