[    2.673155] ip (277) used greatest stack depth: 12360 bytes left
[    2.870437] ip (291) used greatest stack depth: 12352 bytes left
[    8.713626] ip (664) used greatest stack depth: 12344 bytes left
[  713.535806] blackhole_netdev_xmit(): Dropping skb.
[  713.535880] blackhole_netdev_xmit(): Dropping skb.
[  713.535923] blackhole_netdev_xmit(): Dropping skb.
[  713.535977] blackhole_netdev_xmit(): Dropping skb.
[  785.560397] blackhole_netdev_xmit(): Dropping skb.
[  785.560468] blackhole_netdev_xmit(): Dropping skb.
[  785.560519] blackhole_netdev_xmit(): Dropping skb.
[  785.560570] blackhole_netdev_xmit(): Dropping skb.