[    2.286633] ip (274) used greatest stack depth: 12336 bytes left
[    9.644527] ip (913) used greatest stack depth: 12320 bytes left
[ 1115.030479] blackhole_netdev_xmit(): Dropping skb.
[ 1115.030646] blackhole_netdev_xmit(): Dropping skb.
[ 1115.030697] blackhole_netdev_xmit(): Dropping skb.
[ 1115.030736] blackhole_netdev_xmit(): Dropping skb.