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Date: Tue, 29 Jul 2014 09:56:37 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Christoph Lameter <cl@gentwo.org>
Cc: Sasha Levin <sasha.levin@oracle.com>, akpm@linux-foundation.org,
        Gilad Ben-Yossef <gilad@benyossef.com>,
        Thomas Gleixner <tglx@linutronix.de>, Tejun Heo <tj@kernel.org>,
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        linux-kernel@vger.kernel.org, linux-mm@kvack.org, hughd@google.com,
        viresh.kumar@linaro.org, hpa@zytor.com, mingo@kernel.org
Subject: Re: vmstat: On demand vmstat workers V8
Message-ID: <20140729075637.GA19379@twins.programming.kicks-ass.net>
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On Mon, Jul 28, 2014 at 01:55:17PM -0500, Christoph Lameter wrote:
> On Fri, 25 Jul 2014, Sasha Levin wrote:
>=20
> > This patch doesn't interact well with my fuzzing setup. I'm seeing
> > the following:
> >
> > [  490.446927] BUG: using __this_cpu_read() in preemptible [00000000] c=
ode: kworker/16:1/7368
> > [  490.447909] caller is __this_cpu_preempt_check+0x13/0x20
>=20
> __this_cpu_read() from vmstat_update is only called from a kworker that
> is bound to a single cpu. A false positive?

kworkers are never guaranteed to be so, its a 'feature' :/

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