Comment 23 for bug 1788403

Reviewed: https://review.openstack.org/595069
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=4817165fc5938a553fafa1a69c6086f9ebe311af
Submitter: Zuul
Branch: master

commit 4817165fc5938a553fafa1a69c6086f9ebe311af
Author: Matt Riedemann <email address hidden>
Date: Wed Aug 22 10:43:40 2018 -0400

    Wait for network-vif-plugged on resize revert

    Change Id515137747a4b76e9b7057c95f80c8ae74017519 modified
    the libvirt driver to not wait for network-vif-plugged
    events on resize revert, saying that the vifs were never
    unplugged. That's true for the source host but not the dest
    host. The ComputeManager.revert_resize method calls driver.destroy
    and for the libvirt driver, driver.destroy calls cleanup which
    calls unplug_vifs *on the dest host*.

    As of change If00736ab36df4a5a3be4f02b0a550e4bcae77b1b, the API
    will route all events to both the source and dest host while
    the instance has a migration_context. When revert_resize is done
    on the dest host, it RPC casts to finish_revert_resize on the
    source host which calls driver.finish_revert_migration which
    restarts the guest on the source host and plugs vifs. Therefore,
    we can wait for the network-vif-plugged event before changing
    the instance status back to ACTIVE.

    Change-Id: I9e0cffb889c94713c7f28812918103a5d97cefeb
    Related-Bug: #1788403