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Date: Fri, 27 Dec 2013 12:24:22 +0000
From: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
To: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Josh Boyer <jwboyer@fedoraproject.org>,
        Dirk Brandewie <dirk.brandewie@gmail.com>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>,
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        Linux PM list <linux-pm@vger.kernel.org>,
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Subject: Re: intel_pstate divide error with v3.13-rc4-256-gb7000ad
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On Tue, 24 Dec 2013 21:36:01 +0530
Viresh Kumar <viresh.kumar@linaro.org> wrote:

> Adding Dirk..
> 
> On 24 December 2013 20:06, Josh Boyer <jwboyer@fedoraproject.org> wrote:
> > Hi All,
> >
> > We've had a report [1] that the pstate driver causes KVM guests to
> > fail to boot because of a divide error.  See the backtrace below.
> >
> >     4.839784] Intel P-state driver initializing.
> > [    4.859972] Intel pstate controlling: cpu 0
> > [    4.867653] cpufreq: __cpufreq_add_dev: ->get() failed
> 
> After a call to ->init(), ->get() is supposed to work.
> @Dirk: Any idea why it failed?
> 
> And then I don't know what made this divide by zero to happen :)

> > [    4.878127] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011

Emulator bug perhaps ?