Another part of the code that is wrong is cinder.volume.manager.VolumeManager._do_attachment_delete where we have the same issue, we call DB methods instead of OVO methods and the pass the OVO to the notification method.
Another part of the code that is wrong is cinder. volume. manager. VolumeManager. _do_attachment_ delete where we have the same issue, we call DB methods instead of OVO methods and the pass the OVO to the notification method.