Comment 15 for bug 1767422

Reviewed: https://review.openstack.org/567885
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=e08233696816431b3f536bc556928491ecd14e2f
Submitter: Zuul
Branch: stable/ocata

commit e08233696816431b3f536bc556928491ecd14e2f
Author: Miguel Angel Ajo <email address hidden>
Date: Wed May 9 16:23:41 2018 +0200

    Don't delete flows on ports which were on dead vlan during plug

    Ocata codebase of the neutron agent deletes_flows
    when a port has been tagged and already had a tag.

    Later versions implement uninstall_flows to selectively delete
    specific flows, but such patches are big and buggy (have several
    follow up patches).

    This prevents that the patch handling 1767422 will get the DSCP
    flows deleted when port is tagged. Which is detected by functional
    testing.

    I have manually tested that setting a port admin_state_up False,
    and then True, will correctly move the port into dead vlan, and
    then back to non dead vlan, and properly remove the in_port=x,DROP
    openflow rule regardless of this change.

    Related: rhbz#1575706
    Related-Bug: 1767422

    Change-Id: Ib7915ae7bb7f471ff70ce25ce3beb16189ad5394