[    2.376468] ip (277) used greatest stack depth: 12368 bytes left
[    2.421701] ip (281) used greatest stack depth: 12352 bytes left
[   22.531427] ip (2216) used greatest stack depth: 12312 bytes left
[  723.982199] blackhole_netdev_xmit(): Dropping skb.
[  723.982258] blackhole_netdev_xmit(): Dropping skb.
[  723.982296] blackhole_netdev_xmit(): Dropping skb.
[  723.982347] blackhole_netdev_xmit(): Dropping skb.
[  899.095960] blackhole_netdev_xmit(): Dropping skb.
[  899.096029] blackhole_netdev_xmit(): Dropping skb.
[  899.096082] blackhole_netdev_xmit(): Dropping skb.
[  899.096129] blackhole_netdev_xmit(): Dropping skb.