[    2.065702] ip (275) used greatest stack depth: 12320 bytes left
[    7.320705] ip (908) used greatest stack depth: 12304 bytes left
[  621.549066] ip (15282) used greatest stack depth: 12288 bytes left
[  627.609251] ip (15923) used greatest stack depth: 12176 bytes left
[  993.114788] blackhole_netdev_xmit(): Dropping skb.
[  993.114846] blackhole_netdev_xmit(): Dropping skb.
[  993.114882] blackhole_netdev_xmit(): Dropping skb.
[  993.114915] blackhole_netdev_xmit(): Dropping skb.
[ 1181.550196] blackhole_netdev_xmit(): Dropping skb.
[ 1181.550253] blackhole_netdev_xmit(): Dropping skb.
[ 1181.550292] blackhole_netdev_xmit(): Dropping skb.
[ 1181.550322] blackhole_netdev_xmit(): Dropping skb.