[    1.959079] ip (242) used greatest stack depth: 12352 bytes left
[    2.566961] ip (276) used greatest stack depth: 12320 bytes left
[   14.865520] ip (1175) used greatest stack depth: 12272 bytes left
[ 1063.375715] blackhole_netdev_xmit(): Dropping skb.
[ 1063.375808] blackhole_netdev_xmit(): Dropping skb.
[ 1063.375873] blackhole_netdev_xmit(): Dropping skb.
[ 1063.375929] blackhole_netdev_xmit(): Dropping skb.