[    1.827919] ip (240) used greatest stack depth: 12832 bytes left
[    1.860140] ip (243) used greatest stack depth: 12376 bytes left
[    2.422794] ip (274) used greatest stack depth: 12344 bytes left
[    9.322018] ip (913) used greatest stack depth: 12328 bytes left
[   20.811754] ip (2223) used greatest stack depth: 12296 bytes left
[  797.490852] blackhole_netdev_xmit(): Dropping skb.
[  797.490927] blackhole_netdev_xmit(): Dropping skb.
[  797.490965] blackhole_netdev_xmit(): Dropping skb.
[  797.491002] blackhole_netdev_xmit(): Dropping skb.