[    1.641536] ip (246) used greatest stack depth: 12352 bytes left
[    2.079411] ip (277) used greatest stack depth: 12320 bytes left
[    6.428558] ip (663) used greatest stack depth: 12048 bytes left
[  977.857828] blackhole_netdev_xmit(): Dropping skb.
[  977.857907] blackhole_netdev_xmit(): Dropping skb.
[  977.857950] blackhole_netdev_xmit(): Dropping skb.
[  977.857995] blackhole_netdev_xmit(): Dropping skb.
[  989.509753] blackhole_netdev_xmit(): Dropping skb.
[  989.509823] blackhole_netdev_xmit(): Dropping skb.
[  989.509873] blackhole_netdev_xmit(): Dropping skb.
[  989.509938] blackhole_netdev_xmit(): Dropping skb.