[  642.212640] ip (16525) used greatest stack depth: 12168 bytes left
[  946.308868] blackhole_netdev_xmit(): Dropping skb.
[  946.308926] blackhole_netdev_xmit(): Dropping skb.
[  946.308963] blackhole_netdev_xmit(): Dropping skb.
[  946.308995] blackhole_netdev_xmit(): Dropping skb.