[    2.411814] ip (274) used greatest stack depth: 12320 bytes left
[   14.009407] ip (1368) used greatest stack depth: 12304 bytes left
[ 1082.773543] blackhole_netdev_xmit(): Dropping skb.
[ 1082.773604] blackhole_netdev_xmit(): Dropping skb.
[ 1082.773634] blackhole_netdev_xmit(): Dropping skb.
[ 1082.773667] blackhole_netdev_xmit(): Dropping skb.