[    1.784586] ip (243) used greatest stack depth: 12376 bytes left
[    2.301474] ip (274) used greatest stack depth: 12344 bytes left
[   19.276351] ip (2215) used greatest stack depth: 12184 bytes left
[  746.839025] blackhole_netdev_xmit(): Dropping skb.
[  746.839105] blackhole_netdev_xmit(): Dropping skb.
[  746.839150] blackhole_netdev_xmit(): Dropping skb.
[  746.839196] blackhole_netdev_xmit(): Dropping skb.
[  873.056569] blackhole_netdev_xmit(): Dropping skb.
[  873.056632] blackhole_netdev_xmit(): Dropping skb.
[  873.056665] blackhole_netdev_xmit(): Dropping skb.
[  873.056704] blackhole_netdev_xmit(): Dropping skb.