[    1.897762] ip (238) used greatest stack depth: 12376 bytes left
[    2.428944] ip (272) used greatest stack depth: 12344 bytes left
[  646.838855] ip (8644) used greatest stack depth: 12328 bytes left
[ 1084.369296] blackhole_netdev_xmit(): Dropping skb.
[ 1084.369377] blackhole_netdev_xmit(): Dropping skb.
[ 1084.369420] blackhole_netdev_xmit(): Dropping skb.
[ 1084.369457] blackhole_netdev_xmit(): Dropping skb.