[    2.499977] ip (276) used greatest stack depth: 12336 bytes left
[   21.527639] ip (2187) used greatest stack depth: 12320 bytes left
[  966.475522] blackhole_netdev_xmit(): Dropping skb.
[  966.475584] blackhole_netdev_xmit(): Dropping skb.
[  966.475613] blackhole_netdev_xmit(): Dropping skb.
[  966.475644] blackhole_netdev_xmit(): Dropping skb.
[ 1016.182808] blackhole_netdev_xmit(): Dropping skb.
[ 1016.182860] blackhole_netdev_xmit(): Dropping skb.
[ 1016.182892] blackhole_netdev_xmit(): Dropping skb.
[ 1016.182923] blackhole_netdev_xmit(): Dropping skb.