[    2.051550] ip (246) used greatest stack depth: 12376 bytes left
[    2.120579] ip (252) used greatest stack depth: 12328 bytes left
[  639.245418] ip (22420) used greatest stack depth: 12192 bytes left
[  698.829540] blackhole_netdev_xmit(): Dropping skb.
[  698.829598] blackhole_netdev_xmit(): Dropping skb.
[  698.829629] blackhole_netdev_xmit(): Dropping skb.
[  698.829655] blackhole_netdev_xmit(): Dropping skb.
[ 1089.149975] blackhole_netdev_xmit(): Dropping skb.
[ 1089.150046] blackhole_netdev_xmit(): Dropping skb.
[ 1089.150079] blackhole_netdev_xmit(): Dropping skb.
[ 1089.150113] blackhole_netdev_xmit(): Dropping skb.