[    2.299380] ip (274) used greatest stack depth: 12320 bytes left
[    9.283741] ip (912) used greatest stack depth: 12304 bytes left
[  689.748758] blackhole_netdev_xmit(): Dropping skb.
[  689.748824] blackhole_netdev_xmit(): Dropping skb.
[  689.748858] blackhole_netdev_xmit(): Dropping skb.
[  689.748892] blackhole_netdev_xmit(): Dropping skb.
[ 1189.703938] blackhole_netdev_xmit(): Dropping skb.
[ 1189.704003] blackhole_netdev_xmit(): Dropping skb.
[ 1189.704033] blackhole_netdev_xmit(): Dropping skb.
[ 1189.704059] blackhole_netdev_xmit(): Dropping skb.