[    2.018076] ip (245) used greatest stack depth: 12376 bytes left
[    2.674168] ip (276) used greatest stack depth: 12344 bytes left
[  330.145329] ip (3250) used greatest stack depth: 12184 bytes left
[  657.995562] blackhole_netdev_xmit(): Dropping skb.
[  657.995633] blackhole_netdev_xmit(): Dropping skb.
[  657.995674] blackhole_netdev_xmit(): Dropping skb.
[  657.995732] blackhole_netdev_xmit(): Dropping skb.