[    2.007170] ip (241) used greatest stack depth: 12376 bytes left
[    2.666700] ip (275) used greatest stack depth: 12344 bytes left
[   21.961866] ip (2177) used greatest stack depth: 12328 bytes left
[  632.084334] ip (4258) used greatest stack depth: 12184 bytes left
[ 1169.268426] blackhole_netdev_xmit(): Dropping skb.
[ 1169.268482] blackhole_netdev_xmit(): Dropping skb.
[ 1169.268511] blackhole_netdev_xmit(): Dropping skb.
[ 1169.268546] blackhole_netdev_xmit(): Dropping skb.