[    1.862677] ip (241) used greatest stack depth: 12352 bytes left
[    2.376139] ip (275) used greatest stack depth: 12320 bytes left
[  894.742157] blackhole_netdev_xmit(): Dropping skb.
[  894.742232] blackhole_netdev_xmit(): Dropping skb.
[  894.742274] blackhole_netdev_xmit(): Dropping skb.
[  894.742312] blackhole_netdev_xmit(): Dropping skb.