[    2.449227] ip (275) used greatest stack depth: 12336 bytes left
[    9.285762] ip (786) used greatest stack depth: 12192 bytes left
[  709.905865] blackhole_netdev_xmit(): Dropping skb.
[  709.905938] blackhole_netdev_xmit(): Dropping skb.
[  709.905973] blackhole_netdev_xmit(): Dropping skb.
[  709.906008] blackhole_netdev_xmit(): Dropping skb.