[    2.639712] ip (278) used greatest stack depth: 12336 bytes left
[   13.406090] ip (1144) used greatest stack depth: 12320 bytes left
[ 1187.261411] blackhole_netdev_xmit(): Dropping skb.
[ 1187.261576] blackhole_netdev_xmit(): Dropping skb.
[ 1187.261615] blackhole_netdev_xmit(): Dropping skb.
[ 1187.261649] blackhole_netdev_xmit(): Dropping skb.