[    2.274738] ip (275) used greatest stack depth: 12320 bytes left
[    6.516026] ip (646) used greatest stack depth: 12272 bytes left
[   19.592435] ip (2367) used greatest stack depth: 12016 bytes left
[  660.027359] blackhole_netdev_xmit(): Dropping skb.
[  660.027422] blackhole_netdev_xmit(): Dropping skb.
[  660.027455] blackhole_netdev_xmit(): Dropping skb.
[  660.027483] blackhole_netdev_xmit(): Dropping skb.
[  678.264735] blackhole_netdev_xmit(): Dropping skb.
[  678.264798] blackhole_netdev_xmit(): Dropping skb.
[  678.264840] blackhole_netdev_xmit(): Dropping skb.
[  678.264892] blackhole_netdev_xmit(): Dropping skb.
[  851.130013] blackhole_netdev_xmit(): Dropping skb.
[  851.130064] blackhole_netdev_xmit(): Dropping skb.
[  851.130092] blackhole_netdev_xmit(): Dropping skb.
[  851.130126] blackhole_netdev_xmit(): Dropping skb.