[    4.235425] ip (275) used greatest stack depth: 12320 bytes left
[    4.291405] ip (279) used greatest stack depth: 12272 bytes left
[   25.778156] ip (2137) used greatest stack depth: 12048 bytes left
[ 1074.161798] blackhole_netdev_xmit(): Dropping skb.
[ 1074.161892] blackhole_netdev_xmit(): Dropping skb.
[ 1074.161947] blackhole_netdev_xmit(): Dropping skb.
[ 1074.162004] blackhole_netdev_xmit(): Dropping skb.
[ 1186.688028] blackhole_netdev_xmit(): Dropping skb.
[ 1186.688082] blackhole_netdev_xmit(): Dropping skb.
[ 1186.688125] blackhole_netdev_xmit(): Dropping skb.
[ 1186.688164] blackhole_netdev_xmit(): Dropping skb.