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Date: Mon, 4 Oct 2010 15:26:31 -0400
From: Chris Frey <cdfrey@foursquare.net>
To: richard -rw- weinberger <richard.weinberger@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
        user-mode-linux-devel@lists.sourceforge.net
Subject: Re: [uml-devel] um: rcu_sched_state detected stall on CPU 0
Message-ID: <20101004192631.GA30065@foursquare.net>
References: <AANLkTimmwViVHMy-7S3N9Ps1Vj_n_TfJLvwzoupsFPnp@mail.gmail.com>
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On Sat, Oct 02, 2010 at 12:03:04AM +0200, richard -rw- weinberger wrote:
> Hi,
> 
> I'm seeing often messages like this one on my UML:
> ...
> INFO: rcu_sched_state detected stall on CPU 0 (t=7348 jiffies)
> ...
> 
> The system often seems to be frozen.
> When I press a button it wakes up immediately and continues to run.
> 
> Any ideas?
> Config is attached.

I saw this too, but I thought it was because I was overloading my machine.
I only seem to see it when the guest is starved for CPU due to IO on the
host.

- Chris