[    1.917151] ip (241) used greatest stack depth: 12352 bytes left
[    2.555487] ip (275) used greatest stack depth: 12320 bytes left
[    9.765816] ip (794) used greatest stack depth: 12160 bytes left
[ 1061.430014] blackhole_netdev_xmit(): Dropping skb.
[ 1061.430080] blackhole_netdev_xmit(): Dropping skb.
[ 1061.430112] blackhole_netdev_xmit(): Dropping skb.
[ 1061.430143] blackhole_netdev_xmit(): Dropping skb.