[    1.878985] ip (245) used greatest stack depth: 12352 bytes left
[    2.347247] ip (276) used greatest stack depth: 12320 bytes left
[    6.784556] ip (620) used greatest stack depth: 12304 bytes left
[  926.447573] blackhole_netdev_xmit(): Dropping skb.
[  926.447720] blackhole_netdev_xmit(): Dropping skb.
[  926.447775] blackhole_netdev_xmit(): Dropping skb.
[  926.447816] blackhole_netdev_xmit(): Dropping skb.
[  964.649007] blackhole_netdev_xmit(): Dropping skb.
[  964.649063] blackhole_netdev_xmit(): Dropping skb.
[  964.649101] blackhole_netdev_xmit(): Dropping skb.
[  964.649136] blackhole_netdev_xmit(): Dropping skb.