[  232.048041] ip (7642) used greatest stack depth: 12272 bytes left
[  837.051815] ip (27685) used greatest stack depth: 12128 bytes left
[ 1120.140570] blackhole_netdev_xmit(): Dropping skb.
[ 1120.140638] blackhole_netdev_xmit(): Dropping skb.
[ 1120.140680] blackhole_netdev_xmit(): Dropping skb.
[ 1120.140719] blackhole_netdev_xmit(): Dropping skb.