[    1.623952] ip (243) used greatest stack depth: 12352 bytes left
[    2.040211] ip (277) used greatest stack depth: 12320 bytes left
[   16.185324] ip (2107) used greatest stack depth: 12304 bytes left
[  974.564534] blackhole_netdev_xmit(): Dropping skb.
[  974.564618] blackhole_netdev_xmit(): Dropping skb.
[  974.564676] blackhole_netdev_xmit(): Dropping skb.
[  974.564739] blackhole_netdev_xmit(): Dropping skb.
[  975.022802] blackhole_netdev_xmit(): Dropping skb.
[  975.022885] blackhole_netdev_xmit(): Dropping skb.
[  975.022930] blackhole_netdev_xmit(): Dropping skb.
[  975.022979] blackhole_netdev_xmit(): Dropping skb.