[    1.775426] ip (246) used greatest stack depth: 12352 bytes left
[    2.249583] ip (277) used greatest stack depth: 12320 bytes left
[   19.526506] ip (2371) used greatest stack depth: 12160 bytes left
[  638.859557] ip (906) used greatest stack depth: 12032 bytes left
[ 1135.681820] blackhole_netdev_xmit(): Dropping skb.
[ 1135.681879] blackhole_netdev_xmit(): Dropping skb.
[ 1135.681915] blackhole_netdev_xmit(): Dropping skb.
[ 1135.681952] blackhole_netdev_xmit(): Dropping skb.
[ 1219.942831] blackhole_netdev_xmit(): Dropping skb.
[ 1219.942890] blackhole_netdev_xmit(): Dropping skb.
[ 1219.942922] blackhole_netdev_xmit(): Dropping skb.
[ 1219.942956] blackhole_netdev_xmit(): Dropping skb.