[    1.823247] ip (240) used greatest stack depth: 12376 bytes left
[    1.858207] ip (243) used greatest stack depth: 12328 bytes left
[   11.883968] ip (1071) used greatest stack depth: 12168 bytes left
[  662.465483] blackhole_netdev_xmit(): Dropping skb.
[  662.465549] blackhole_netdev_xmit(): Dropping skb.
[  662.465586] blackhole_netdev_xmit(): Dropping skb.
[  662.465622] blackhole_netdev_xmit(): Dropping skb.