[    2.617029] ip (275) used greatest stack depth: 12320 bytes left
[  720.994824] blackhole_netdev_xmit(): Dropping skb.
[  720.994897] blackhole_netdev_xmit(): Dropping skb.
[  720.994940] blackhole_netdev_xmit(): Dropping skb.
[  720.994977] blackhole_netdev_xmit(): Dropping skb.