[    1.800753] ip (242) used greatest stack depth: 12360 bytes left
[    2.384703] ip (276) used greatest stack depth: 12328 bytes left
[  997.627005] blackhole_netdev_xmit(): Dropping skb.
[  997.627081] blackhole_netdev_xmit(): Dropping skb.
[  997.627114] blackhole_netdev_xmit(): Dropping skb.
[  997.627146] blackhole_netdev_xmit(): Dropping skb.