Comment 11 for bug 1884217

> I don't know how this is happen:
"This is fixed once the resource tracker comes along and corrects the information in placement,"
but that logic might be extended to the _unprovision case to solve the issue.

I think this is referring to how the resource tracker sets a node to reserved=True if the node info from ironic indicates the node is not AVAILABLE for provisioning in update_provider_tree during the update_available_resource periodic task in nova-compute.

[1] https://github.com/openstack/nova/blob/d5b6412ef52b1e5ad797a49850c9c6701b0405db/nova/virt/ironic/driver.py#L876-L885