[    2.214520] ip (276) used greatest stack depth: 12320 bytes left
[   11.863904] ip (1170) used greatest stack depth: 12160 bytes left
[  743.455986] blackhole_netdev_xmit(): Dropping skb.
[  743.456050] blackhole_netdev_xmit(): Dropping skb.
[  743.456092] blackhole_netdev_xmit(): Dropping skb.
[  743.456134] blackhole_netdev_xmit(): Dropping skb.
[  967.568003] blackhole_netdev_xmit(): Dropping skb.
[  967.568072] blackhole_netdev_xmit(): Dropping skb.
[  967.568108] blackhole_netdev_xmit(): Dropping skb.
[  967.568144] blackhole_netdev_xmit(): Dropping skb.