[    2.215973] ip (274) used greatest stack depth: 12344 bytes left
[    9.361832] ip (914) used greatest stack depth: 12328 bytes left
[ 1118.361349] blackhole_netdev_xmit(): Dropping skb.
[ 1118.361423] blackhole_netdev_xmit(): Dropping skb.
[ 1118.361460] blackhole_netdev_xmit(): Dropping skb.
[ 1118.361506] blackhole_netdev_xmit(): Dropping skb.