From mboxrd@z Thu Jan  1 00:00:00 1970
From: James Thomason <james@divide.org>
Subject: Re: Guest Hang Bugs
Date: Thu, 15 Jan 2009 14:49:30 -0800
Message-ID: <C594FD7A.6251%james@divide.org>
References: <496F55EB.6040506@redhat.com>
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To: Avi Kivity <avi@redhat.com>
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On 1/15/09 7:27 AM, "Avi Kivity" <avi@redhat.com> wrote:
 
> Cam you try adding clocksource=acpi_pm to the _guest_ kernel command line?

Avi, 

I booted the guest with clocksource=acpi_pm and it has been running under
heavy load for about 4 hours with kvm -smp 12.  Considering that the guest
previously would not even boot with kvm -smp 12, I think this is the root
cause.  As another data point, I was not able to trigger the bug when
running a guest with all active cores on socket 0 only, but I was able to
trigger it when putting half the cores on socket 1.  So in a nutshell the
kernel uses an unreliable clock source by default on SMP systems?

Thanks for your help!

Regards, 
James