[    2.429317] ip (275) used greatest stack depth: 12320 bytes left
[   21.616717] ip (2186) used greatest stack depth: 12304 bytes left
[  747.692773] blackhole_netdev_xmit(): Dropping skb.
[  747.692847] blackhole_netdev_xmit(): Dropping skb.
[  747.692881] blackhole_netdev_xmit(): Dropping skb.
[  747.692929] blackhole_netdev_xmit(): Dropping skb.
[  916.069467] blackhole_netdev_xmit(): Dropping skb.
[  916.069527] blackhole_netdev_xmit(): Dropping skb.
[  916.069557] blackhole_netdev_xmit(): Dropping skb.
[  916.069583] blackhole_netdev_xmit(): Dropping skb.