Comment 9 for bug 1666831

Turns out that the fix for this bug accidentally broke boot-from-volume setups that use NFS. In particular, this line:

https://github.com/openstack/nova/blob/stable/ocata/nova/virt/libvirt/driver.py#L1149

 if os.path.exists(inst_base) and not root_disk.exists():

needs to be changed to this in order to prevent BFV instances from being destroyed on resize...

 if os.path.exists(inst_base) and not root_disk.exists() and not compute_utils.is_volume_backed_instance(instance._context, instance):

I'll open a new bug for this.