[    2.362483] ip (280) used greatest stack depth: 12360 bytes left
[    2.571932] ip (294) used greatest stack depth: 12344 bytes left
[    9.046227] ip (787) used greatest stack depth: 12288 bytes left
[   12.320802] ip (1091) used greatest stack depth: 12064 bytes left
[  919.676555] blackhole_netdev_xmit(): Dropping skb.
[  919.676615] blackhole_netdev_xmit(): Dropping skb.
[  919.676650] blackhole_netdev_xmit(): Dropping skb.
[  919.676682] blackhole_netdev_xmit(): Dropping skb.
[ 1063.817005] blackhole_netdev_xmit(): Dropping skb.
[ 1063.817077] blackhole_netdev_xmit(): Dropping skb.
[ 1063.817113] blackhole_netdev_xmit(): Dropping skb.
[ 1063.817147] blackhole_netdev_xmit(): Dropping skb.
[ 1074.997227] blackhole_netdev_xmit(): Dropping skb.
[ 1074.997281] blackhole_netdev_xmit(): Dropping skb.
[ 1074.997313] blackhole_netdev_xmit(): Dropping skb.
[ 1074.997339] blackhole_netdev_xmit(): Dropping skb.