Comment 0 for bug 1330503

During compute manager startup init_host is called. One of the functions there is to delete instance data that doesn't belong to this host i.e. _destroy_evacuated_instances. But this function only checks if the local instance belongs to the host or not. It doesn't check the task_state.

If at this time a a resize migration is taking place and the destination compute manager is restarted it might destroy the resizing instance.

A similar bug concerning just the migrating state is outlined here: https://bugs.launchpad.net/nova/+bug/1319797 and a fix is proposed here: https://review.openstack.org/#/c/93903

It was intended to have that fix deal with resize migrating instances as well as those just in the migrating state but as pointed out in a review comment this solution will work for migrating but a fix for resize would require further changes so I have raised this bug to highlight that.