[    1.924552] ip (240) used greatest stack depth: 12384 bytes left
[    2.589060] ip (275) used greatest stack depth: 12368 bytes left
[    2.639257] ip (279) used greatest stack depth: 12352 bytes left
[   12.369261] ip (1072) used greatest stack depth: 12200 bytes left
[  849.107517] blackhole_netdev_xmit(): Dropping skb.
[  849.107672] blackhole_netdev_xmit(): Dropping skb.
[  849.107716] blackhole_netdev_xmit(): Dropping skb.
[  849.107760] blackhole_netdev_xmit(): Dropping skb.
[  975.660188] blackhole_netdev_xmit(): Dropping skb.
[  975.660265] blackhole_netdev_xmit(): Dropping skb.
[  975.660311] blackhole_netdev_xmit(): Dropping skb.
[  975.660360] blackhole_netdev_xmit(): Dropping skb.