[    2.351807] ip (277) used greatest stack depth: 12320 bytes left
[  649.039198] blackhole_netdev_xmit(): Dropping skb.
[  649.039272] blackhole_netdev_xmit(): Dropping skb.
[  649.039314] blackhole_netdev_xmit(): Dropping skb.
[  649.039358] blackhole_netdev_xmit(): Dropping skb.