[    1.912792] ip (244) used greatest stack depth: 12376 bytes left
[    2.466805] ip (275) used greatest stack depth: 12344 bytes left
[   14.549447] ip (1364) used greatest stack depth: 12328 bytes left
[  993.243910] blackhole_netdev_xmit(): Dropping skb.
[  993.244005] blackhole_netdev_xmit(): Dropping skb.
[  993.244052] blackhole_netdev_xmit(): Dropping skb.
[  993.244094] blackhole_netdev_xmit(): Dropping skb.