[    2.141166] ip (275) used greatest stack depth: 12320 bytes left
[    4.362806] ip (405) used greatest stack depth: 12304 bytes left
[   21.387927] ip (2506) used greatest stack depth: 12160 bytes left
[ 1202.078538] blackhole_netdev_xmit(): Dropping skb.
[ 1202.078605] blackhole_netdev_xmit(): Dropping skb.
[ 1202.078645] blackhole_netdev_xmit(): Dropping skb.
[ 1202.078687] blackhole_netdev_xmit(): Dropping skb.