[    1.837613] ip (242) used greatest stack depth: 12368 bytes left
[    2.354080] ip (276) used greatest stack depth: 12336 bytes left
[    5.198073] ip (445) used greatest stack depth: 12160 bytes left
[  749.505347] blackhole_netdev_xmit(): Dropping skb.
[  749.505437] blackhole_netdev_xmit(): Dropping skb.
[  749.505476] blackhole_netdev_xmit(): Dropping skb.
[  749.505529] blackhole_netdev_xmit(): Dropping skb.
[  813.725789] blackhole_netdev_xmit(): Dropping skb.
[  813.725844] blackhole_netdev_xmit(): Dropping skb.
[  813.725875] blackhole_netdev_xmit(): Dropping skb.
[  813.725907] blackhole_netdev_xmit(): Dropping skb.