[    1.780636] ip (241) used greatest stack depth: 12376 bytes left
[    2.259218] ip (275) used greatest stack depth: 12344 bytes left
[  837.799344] blackhole_netdev_xmit(): Dropping skb.
[  837.799405] blackhole_netdev_xmit(): Dropping skb.
[  837.799435] blackhole_netdev_xmit(): Dropping skb.
[  837.799460] blackhole_netdev_xmit(): Dropping skb.
[  908.104233] blackhole_netdev_xmit(): Dropping skb.
[  908.104303] blackhole_netdev_xmit(): Dropping skb.
[  908.104356] blackhole_netdev_xmit(): Dropping skb.
[  908.104416] blackhole_netdev_xmit(): Dropping skb.