Due to the lack of capabilites that LXC has in libvirt (no cpu info, socket info, etc). Compute will fail if you specificy something other than qemu as a --libvirt-flag. See attached traceback:
(nova.exception): TRACE: Traceback (most recent call last):
(nova.exception): TRACE: File "/home/ubuntu/work/nova-lxc/nova/exception.py", line 120, in _wrap
(nova.exception): TRACE: return f(*args, **kw)
(nova.exception): TRACE: File "/home/ubuntu/work/nova-lxc/nova/compute/manager.py", line 799, in update_available_resource
(nova.exception): TRACE: return self.driver.update_available_resource(context, self.host)
(nova.exception): TRACE: File "/home/ubuntu/work/nova-lxc/nova/virt/libvirt_conn.py", line 1095, in update_available_resource
(nova.exception): TRACE: 'cpu_info': self.get_cpu_info()}
(nova.exception): TRACE: File "/home/ubuntu/work/nova-lxc/nova/virt/libvirt_conn.py", line 1012, in get_cpu_info
(nova.exception): TRACE: cpu_info['model'] = xml.xpathEval('//cpu/model')[0].getContent()
(nova.exception): TRACE: IndexError: list index out of range
(nova.exception): TRACE:
2011-03-14 22:06:56,935 CRITICAL nova [-] list index out of range
(nova): TRACE: Traceback (most recent call last):
(nova): TRACE: File "./bin/nova-compute", line 48, in <module>
(nova): TRACE: service.serve()
(nova): TRACE: File "/home/ubuntu/work/nova-lxc/nova/service.py", line 284, in serve
(nova): TRACE: x.start()
(nova): TRACE: File "/home/ubuntu/work/nova-lxc/nova/service.py", line 96, in start
(nova): TRACE: self.manager.update_available_resource(ctxt)
(nova): TRACE: File "/home/ubuntu/work/nova-lxc/nova/exception.py", line 126, in _wrap
(nova): TRACE: raise Error(str(e))
(nova): TRACE: Error: list index out of range