Comment 1 for bug 1943679

Perhaps not related but another failure for test_trunk_subport_lifecycle:
https://review.opendev.org/c/openstack/neutron/+/809268
https://dd25c8fff5148bff9a3d-e4098ecd70541ccfec6de5edaad12e3e.ssl.cf5.rackcdn.com/809268/1/check/neutron-tempest-plugin-scenario-openvswitch/aafed35/testr_results.html

This time the exception was this:
tempest.lib.exceptions.Conflict: Conflict with state of target resource
Details: {'type': 'PortInUse', 'message': 'Unable to complete operation on port 62105403-77f1-4f28-a2d8-54e64048def7 for network b528d78b-5f74-4b74-8a2e-6cb71c06ec79. Port already has an attached device 985e5be8-0e5f-48e6-abb7-59b961828205.', 'detail': ''}

So it seems that the after the suports are removed from the trunk of VM2 (see https://opendev.org/openstack/neutron-tempest-plugin/src/branch/master/neutron_tempest_plugin/scenario/test_trunk.py#L266 ) and the ports go down, the suports can't be added to the trunk of vm2 as the subport still has an attached device id