[OVN][QoS] "qos-fip" extension always loaded even without ML2 "qos", error while processing extensions

[Rodolfo Alonso]

Since [1][2], QoS is implemented for OVN. If ML2 QoS service plugin is not loaded, OVN L3 QoS extension should not be loaded neither.

As reported in [3], without the ML2 QoS driver loaded [4], the "qos-fip" extension fails during the initialization: the driver is loaded but the extension is not supported by any plugin, raising an exception [5].

[1]https://review.opendev.org/#/c/722415/
[2]https://bugs.launchpad.net/neutron/+bug/1877408
[3]https://zuul.opendev.org/t/openstack/build/2e85321c072f4deebc456b75bda0fbf4/log/controller/logs/screen-q-svc.txt#551
[4]https://storage.gra.cloud.ovh.net/v1/AUTH_dcaab5e32b234d56b626f72581e3644c/zuul_opendev_logs_4ee/755726/4/check/kuryr-kubernetes-tempest-containerized-ovn/4ee7612/controller/logs/local_conf.txt
[5]http://paste.openstack.org/show/798773/

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/756483

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/756483
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=7e31f2ae41b4512afd2b3dd4fb72fcd16ef0a373
Submitter: Zuul
Branch: master

commit 7e31f2ae41b4512afd2b3dd4fb72fcd16ef0a373
Author: Rodolfo Alonso Hernandez <email address hidden>
Date: Wed Oct 7 10:20:20 2020 +0000

    Do not load "qos-fip" if "qos" plugin is not loaded

    If QoS service plugin is not loaded, the L3 QoS extension in the OVN
    L3 plugin should not be loaded neither.

    Prior to this patch, the extension drivers were checked to find the
    QoS extension. Although it is a misconfiguration to have the QoS
    extension without loading the QoS driver, that is handled correctly
    by the Neutron server, disabling the extension silently.

    Closes-Bug: #1898842
    Related-Bug: #1877408

    Change-Id: Iea5ff76fe652ab1c04e23850b9259547c1d54365

[Rodolfo Alonso (rodolfo-alonso-hernandez)]

This bug is due to [1] that is only in master (Wallaby).

[1]https://review.opendev.org/c/openstack/neutron/+/722415

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 18.0.0.0rc1 release candidate.