[    2.645795] ip (275) used greatest stack depth: 12320 bytes left
[   26.528956] ip (2380) used greatest stack depth: 12128 bytes left
[ 1255.512319] blackhole_netdev_xmit(): Dropping skb.
[ 1255.512389] blackhole_netdev_xmit(): Dropping skb.
[ 1255.512422] blackhole_netdev_xmit(): Dropping skb.
[ 1255.512473] blackhole_netdev_xmit(): Dropping skb.