[    1.733908] ip (242) used greatest stack depth: 12360 bytes left
[    2.315999] ip (276) used greatest stack depth: 12328 bytes left
[  645.099570] ip (21625) used greatest stack depth: 12048 bytes left
[  807.920595] blackhole_netdev_xmit(): Dropping skb.
[  807.920653] blackhole_netdev_xmit(): Dropping skb.
[  807.920685] blackhole_netdev_xmit(): Dropping skb.
[  807.920716] blackhole_netdev_xmit(): Dropping skb.
[  972.722360] blackhole_netdev_xmit(): Dropping skb.
[  972.722432] blackhole_netdev_xmit(): Dropping skb.
[  972.722480] blackhole_netdev_xmit(): Dropping skb.
[  972.722530] blackhole_netdev_xmit(): Dropping skb.