Ah it's not a scheduler filter (which is what I thought was related to this), it's a libvirt firewall driver network filter:

http://logs.openstack.org/24/374324/1/gate/gate-tempest-dsvm-cells-ubuntu-xenial/81f45de/logs/screen-n-cpu.txt.gz?level=TRACE#_2016-09-21_21_20_24_446

2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [req-462fe36b-6d85-4b74-9eab-4d2a0ea9c3d5 tempest-ListImageFiltersTestJSON-1517708761 tempest-ListImageFiltersTestJSON-1517708761] [instance: 9103de54-6d83-4877-8075-9807ec099778] Instance failed to spawn
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778] Traceback (most recent call last):
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]   File "/opt/stack/new/nova/nova/compute/manager.py", line 2078, in _build_resources
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]     yield resources
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]   File "/opt/stack/new/nova/nova/compute/manager.py", line 1920, in _build_and_run_instance
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]     block_device_info=block_device_info)
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]   File "/opt/stack/new/nova/nova/virt/libvirt/driver.py", line 2583, in spawn
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]     post_xml_callback=gen_confdrive)
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]   File "/opt/stack/new/nova/nova/virt/libvirt/driver.py", line 4816, in _create_domain_and_network
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]     network_info)
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]   File "/opt/stack/new/nova/nova/virt/libvirt/firewall.py", line 339, in setup_basic_filtering
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]     self.nwfilter.setup_basic_filtering(instance, network_info)
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]   File "/opt/stack/new/nova/nova/virt/libvirt/firewall.py", line 122, in setup_basic_filtering
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]     self._ensure_static_filters()
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]   File "/opt/stack/new/nova/nova/virt/libvirt/firewall.py", line 225, in _ensure_static_filters
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]     self._define_filter(self.nova_no_nd_reflection_filter())
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]   File "/opt/stack/new/nova/nova/virt/libvirt/firewall.py", line 262, in _define_filter
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]     self._conn.nwfilterDefineXML(xml)
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]   File "/usr/local/lib/python2.7/dist-packages/eventlet/tpool.py", line 186, in doit
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]     result = proxy_call(self._autowrap, f, *args, **kwargs)
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]   File "/usr/local/lib/python2.7/dist-packages/eventlet/tpool.py", line 144, in proxy_call
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]     rv = execute(f, *args, **kwargs)
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]   File "/usr/local/lib/python2.7/dist-packages/eventlet/tpool.py", line 125, in execute
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]     six.reraise(c, e, tb)
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]   File "/usr/local/lib/python2.7/dist-packages/eventlet/tpool.py", line 83, in tworker
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]     rv = meth(*args, **kwargs)
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]   File "/usr/local/lib/python2.7/dist-packages/libvirt.py", line 4341, in nwfilterDefineXML
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]     if ret is None:raise libvirtError('virNWFilterDefineXML() failed', conn=self)
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778] libvirtError: operation failed: filter 'nova-no-nd-reflection' already exists with uuid e740c5ec-c715-4f73-9874-630cc73d4ac2
2016-09-21 21:20:24.446 12207 ERROR nova.compute.manager [instance: 9103de54-6d83-4877-8075-9807ec099778]