Comment 22 for bug 1268906

I've had a number of lockups in the last 2 days since upgrading to Trusty and trying to run a VM under kvm which look to match this issue.

System appears to become unresponsive/hang with what looks like some kind of I/O lockup, cannot ls in a terminal etc before eventually display freezes. syslog shows kernel spew related to soft lockup after this point though.

The issue appeared to coincide with a period of high disk I/O within the guest on both occasions. I'll look to reproduce on a less active guest outside of working day.

This occured on a 64 bit system:

lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu Trusty Tahr (development branch)
Release: 14.04
Codename: trusty

uname -a
Linux moon127-pcsubu 3.13.0-12-generic #32-Ubuntu SMP Fri Feb 21 17:45:10 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux