[    2.552680] ip (277) used greatest stack depth: 12320 bytes left
[   13.020515] ip (1171) used greatest stack depth: 12224 bytes left
[  877.280868] blackhole_netdev_xmit(): Dropping skb.
[  877.280930] blackhole_netdev_xmit(): Dropping skb.
[  877.280959] blackhole_netdev_xmit(): Dropping skb.
[  877.280990] blackhole_netdev_xmit(): Dropping skb.
[ 1041.732539] blackhole_netdev_xmit(): Dropping skb.
[ 1041.732611] blackhole_netdev_xmit(): Dropping skb.
[ 1041.732650] blackhole_netdev_xmit(): Dropping skb.
[ 1041.732690] blackhole_netdev_xmit(): Dropping skb.