[    2.643942] ip (276) used greatest stack depth: 12368 bytes left
[    5.328566] ip (411) used greatest stack depth: 12336 bytes left
[   11.013025] ip (946) used greatest stack depth: 12200 bytes left
[ 1127.950076] blackhole_netdev_xmit(): Dropping skb.
[ 1127.950244] blackhole_netdev_xmit(): Dropping skb.
[ 1127.950292] blackhole_netdev_xmit(): Dropping skb.
[ 1127.950327] blackhole_netdev_xmit(): Dropping skb.