This seems to also affect keepalived `use_vmac` configurations, where
the keepalived VIPs are configured on macvlan interfaces. After a
stretch kernel update from 4.9.0-11-amd64 (4.9.189) to 4.9.0-12-amd64
(4.9.209) the keepalived VIPs stop responding to ARP queries, causing
the VIP to remain configured but unreachable on the VRRP master.
