[    1.562282] ip (246) used greatest stack depth: 12352 bytes left
[    1.891335] ip (277) used greatest stack depth: 12320 bytes left
[   18.386666] ip (2330) used greatest stack depth: 12304 bytes left
[  696.968504] blackhole_netdev_xmit(): Dropping skb.
[  696.968579] blackhole_netdev_xmit(): Dropping skb.
[  696.968620] blackhole_netdev_xmit(): Dropping skb.
[  696.968679] blackhole_netdev_xmit(): Dropping skb.
[  783.124253] blackhole_netdev_xmit(): Dropping skb.
[  783.124315] blackhole_netdev_xmit(): Dropping skb.
[  783.124354] blackhole_netdev_xmit(): Dropping skb.
[  783.124402] blackhole_netdev_xmit(): Dropping skb.