Comment 10 for bug 1418097

I opened a bug on OVS. A few thoughts, but first let's translate that script to English:

1) Create a bridge
2) Create a namespace
3) Create a port on the bridge
4) Move the port to the namespace
5) Delete the namespace
6) Delete the bridge (Internally, this deletes the port, and that's where the crash happens)

If we reverse steps 5 and 6, the issue is avoided. This is not to say that we're not facing an OVS bug, but still, we could work around it by the time the potential fix hits OVS and is (Maybe) backported to relevant versions.

Explicitly deleting the interface before deleting the namespace also avoids the issue.

This is to suggest that there's some DVR interface (qg, fpr, frp?) that is not being deleted explicitly during the offending DVR functional test, and thus when a DVR router is deleted outside of a testing context.

To conclude, while we're definitely facing an OVS bug, I think that we have a Neutron DVR bug here as well that should be fixed regardless of any OVS fixes.