Comment 4 for bug 1567668

Luckily, the issue was reproduced here and we do have logs!
http://logs.openstack.org/94/303594/2/check/gate-neutron-dsvm-functional/1f86f1d/

After looking into the logs, I think the culprit is not the mentioned https://review.openstack.org/#/c/298056/ and this patch deserves an apology . Looking at ps output after job was finished we can see the stuck processes: one of them has pid 30938.

The last message in logs from this process is at 2016-04-08 20:27:59.522 where neutron.tests.functional.agent.test_l2_ovs_agent.TestOVSAgent.test_ancillary_port_creation_and_deletion_native job failed and likely got stuck: http://logs.openstack.org/94/303594/2/check/gate-neutron-dsvm-functional/1f86f1d/logs/dsvm-functional-logs/neutron.tests.functional.agent.test_l2_ovs_agent.TestOVSAgent.test_ancillary_port_creation_and_deletion_native_.txt.gz#_2016-04-08_20_27_59_522

The other stuck process 30940 has the same exception: http://logs.openstack.org/94/303594/2/check/gate-neutron-dsvm-functional/1f86f1d/logs/dsvm-functional-logs/neutron.tests.functional.agent.test_ovs_lib.OVSBridgeTestCase.test_delete_port_if_exists_false_native_.txt.gz#_2016-04-08_20_40_05_584

Both from the above links are the last messages from that process.