[    2.469585] ip (275) used greatest stack depth: 12336 bytes left
[   10.547396] ip (961) used greatest stack depth: 12176 bytes left
[  901.798115] blackhole_netdev_xmit(): Dropping skb.
[  901.798189] blackhole_netdev_xmit(): Dropping skb.
[  901.798228] blackhole_netdev_xmit(): Dropping skb.
[  901.798264] blackhole_netdev_xmit(): Dropping skb.