Comment 9 for bug 1798904

actully maybe not if this affect ml2/ovs with ovs/noop firewall driver
we will still need https://review.opendev.org/c/openstack/nova/+/602432

which is requried to fix the remain edgecase for https://bugs.launchpad.net/neutron/+bug/1734320
also.

unfortunetlly to backport that patch we need to backport the following set of patches.

live migration backports
https://review.opendev.org/c/openstack/nova/+/747454/4
https://review.opendev.org/c/openstack/nova/+/742180/12
https://review.opendev.org/c/openstack/nova/+/767368
https://review.opendev.org/c/openstack/neutron/+/640258
https://review.opendev.org/c/openstack/nova/+/602432
https://review.opendev.org/c/openstack/neutron/+/766277
https://review.opendev.org/c/openstack/neutron/+/753314

most of which are being backpoted anyway but to fully fix both issues we need to fix a race inside neutron and what ports the l2 agent will process that then allows us to delegate port plugin to os-vif in all cases regarding ovs which allwos us to remove the libvirt race for
https://bugs.launchpad.net/neutron/+bug/1734320

while the libvirt race is not relevent for this bug as its cause by the admin status it is relevent to be able to use os-vif to enfoce the dead vlan since we cant add the interface to the isolated dead vlan using libvirt directly.

so both bugs need to delegate port plugging to os-vif to allow addign it to the isolated vlan.
the other bug also need that to avoid the race on live migration.