[    2.321473] ip (274) used greatest stack depth: 12344 bytes left
[    7.530820] ip (745) used greatest stack depth: 12328 bytes left
[  721.420143] blackhole_netdev_xmit(): Dropping skb.
[  721.420203] blackhole_netdev_xmit(): Dropping skb.
[  721.420232] blackhole_netdev_xmit(): Dropping skb.
[  721.420274] blackhole_netdev_xmit(): Dropping skb.
[ 1105.470887] blackhole_netdev_xmit(): Dropping skb.
[ 1105.470958] blackhole_netdev_xmit(): Dropping skb.
[ 1105.471005] blackhole_netdev_xmit(): Dropping skb.
[ 1105.471047] blackhole_netdev_xmit(): Dropping skb.