[    2.520008] ip (279) used greatest stack depth: 12328 bytes left
[   28.504223] ip (2468) used greatest stack depth: 12312 bytes left
[  888.915263] blackhole_netdev_xmit(): Dropping skb.
[  888.915335] blackhole_netdev_xmit(): Dropping skb.
[  888.915383] blackhole_netdev_xmit(): Dropping skb.
[  888.915437] blackhole_netdev_xmit(): Dropping skb.