[    2.528221] ip (276) used greatest stack depth: 12360 bytes left
[    2.574793] ip (280) used greatest stack depth: 12344 bytes left
[  644.926305] ip (21084) used greatest stack depth: 12312 bytes left
[  833.187169] blackhole_netdev_xmit(): Dropping skb.
[  833.187233] blackhole_netdev_xmit(): Dropping skb.
[  833.187269] blackhole_netdev_xmit(): Dropping skb.
[  833.187304] blackhole_netdev_xmit(): Dropping skb.
[  904.651533] blackhole_netdev_xmit(): Dropping skb.
[  904.651596] blackhole_netdev_xmit(): Dropping skb.
[  904.651642] blackhole_netdev_xmit(): Dropping skb.
[  904.651700] blackhole_netdev_xmit(): Dropping skb.
[  947.272238] blackhole_netdev_xmit(): Dropping skb.
[  947.272307] blackhole_netdev_xmit(): Dropping skb.
[  947.272344] blackhole_netdev_xmit(): Dropping skb.
[  947.272390] blackhole_netdev_xmit(): Dropping skb.
[  953.799183] ip (20298) used greatest stack depth: 12072 bytes left