Comment 11 for bug 1257644

The logic here is killing me:

https://review.openstack.org/#/c/56224/4/nova/virt/libvirt/driver.py

I'm not really sure how that "AUTO:" prefix is going to be set on the disabled_reason when disabling the service, especially with the changes to _close_callback here:

https://review.openstack.org/#/c/52189/9/nova/virt/libvirt/driver.py

It looks like if the connection that's being closed is not the one that we registered the callback against (not sure how that would happen?), then the _error var isn't defined and you'd get a NameError at runtime.