[    2.449976] ip (275) used greatest stack depth: 12320 bytes left
[   18.747803] ip (2102) used greatest stack depth: 12304 bytes left
[  643.135690] ip (25230) used greatest stack depth: 12272 bytes left
[ 1099.782224] blackhole_netdev_xmit(): Dropping skb.
[ 1099.782280] blackhole_netdev_xmit(): Dropping skb.
[ 1099.782314] blackhole_netdev_xmit(): Dropping skb.
[ 1099.782346] blackhole_netdev_xmit(): Dropping skb.
[ 1127.399257] blackhole_netdev_xmit(): Dropping skb.
[ 1127.399322] blackhole_netdev_xmit(): Dropping skb.
[ 1127.399359] blackhole_netdev_xmit(): Dropping skb.
[ 1127.399395] blackhole_netdev_xmit(): Dropping skb.