[  247.813583] ip (13933) used greatest stack depth: 12296 bytes left
[  869.955431] ip (23159) used greatest stack depth: 12072 bytes left
[ 1036.349763] blackhole_netdev_xmit(): Dropping skb.
[ 1036.349817] blackhole_netdev_xmit(): Dropping skb.
[ 1036.349851] blackhole_netdev_xmit(): Dropping skb.
[ 1036.349889] blackhole_netdev_xmit(): Dropping skb.
[ 1271.003584] blackhole_netdev_xmit(): Dropping skb.
[ 1271.003658] blackhole_netdev_xmit(): Dropping skb.
[ 1271.003693] blackhole_netdev_xmit(): Dropping skb.
[ 1271.003736] blackhole_netdev_xmit(): Dropping skb.