[    1.875507] ip (243) used greatest stack depth: 12368 bytes left
[    2.431709] ip (277) used greatest stack depth: 12336 bytes left
[   12.805720] ip (1172) used greatest stack depth: 12176 bytes left
[  733.180894] blackhole_netdev_xmit(): Dropping skb.
[  733.180987] blackhole_netdev_xmit(): Dropping skb.
[  733.181039] blackhole_netdev_xmit(): Dropping skb.
[  733.181093] blackhole_netdev_xmit(): Dropping skb.
[  909.619272] blackhole_netdev_xmit(): Dropping skb.
[  909.619341] blackhole_netdev_xmit(): Dropping skb.
[  909.619377] blackhole_netdev_xmit(): Dropping skb.
[  909.619416] blackhole_netdev_xmit(): Dropping skb.