[    1.825705] ip (242) used greatest stack depth: 12416 bytes left
[    2.329555] ip (276) used greatest stack depth: 12320 bytes left
[    5.217230] ip (440) used greatest stack depth: 12032 bytes left
[  645.361444] blackhole_netdev_xmit(): Dropping skb.
[  645.361514] blackhole_netdev_xmit(): Dropping skb.
[  645.361547] blackhole_netdev_xmit(): Dropping skb.
[  645.361589] blackhole_netdev_xmit(): Dropping skb.
[  855.452510] blackhole_netdev_xmit(): Dropping skb.
[  855.452562] blackhole_netdev_xmit(): Dropping skb.
[  855.452593] blackhole_netdev_xmit(): Dropping skb.
[  855.452625] blackhole_netdev_xmit(): Dropping skb.