[    2.096023] ip (277) used greatest stack depth: 12320 bytes left
[  624.047009] ip (10871) used greatest stack depth: 12304 bytes left
[  729.532608] blackhole_netdev_xmit(): Dropping skb.
[  729.532680] blackhole_netdev_xmit(): Dropping skb.
[  729.532727] blackhole_netdev_xmit(): Dropping skb.
[  729.532771] blackhole_netdev_xmit(): Dropping skb.
[ 1136.571258] blackhole_netdev_xmit(): Dropping skb.
[ 1136.571332] blackhole_netdev_xmit(): Dropping skb.
[ 1136.571370] blackhole_netdev_xmit(): Dropping skb.
[ 1136.571412] blackhole_netdev_xmit(): Dropping skb.