Re: BUG: Guest lockup and 100% CPU load on host

[Jan Bernauer <bernauer@kph.uni-mainz.de>]

Hi,

 thanks for the info! It seems quite stable now, but I haven't tried
-smp 2 yet.

 Timing problems seem plausible: I have a dvb-card passed through to the
guest. With normal setup, the frontend detection of the driver module
breaks every other try with a i2c timeout.
I changed the cpufreq governor of the host from ondemand to performance,
and the guest seemed stable, until suddenly the timeouts filled the logs
again.

Until now, with clocksource=acpi_pm, I saw only occasional irq timeouts
of the card (like, under 10 in 30 minutes), under heavy load of the guest.


James Thomason wrote:
> I spent some time with the same problem over the last two days.  Avi Kivity
> suggested adding "clocksource=acpi_pm" to the guest kernel boot line, and
> that seems to have resolved the issue. Would you give that a try and let me
> know the result?  Also I believe the following bugs might be related:
> 
> [ 2351676 ] Guests hang periodically on Ubuntu-8.10
> [ 2353811 ] Solaris 10 guest unstable
> [ 2494730 ] Guests "stalling" on kvm-82
> [ 2138079 ] kvm locks up system
> [ 2113643 ] guests AND host still getting stuck under CPU load
> 



Best regards,
Jan


-- 
Jan C. Bernauer                       email: bernauer@kph.uni-mainz.de
Institut für Kernphysik               tel  : 06131 - 39 25826
Johannes-Gutenberg-Universität Mainz  fax  : 06131 - 39 22964
Johann-Joachim-Becher-Weg 45
55099 Mainz