[    1.965112] ip (241) used greatest stack depth: 12376 bytes left
[    2.572735] ip (275) used greatest stack depth: 12360 bytes left
[    2.772258] ip (289) used greatest stack depth: 12344 bytes left
[    5.460354] ip (438) used greatest stack depth: 12200 bytes left
[  683.603723] blackhole_netdev_xmit(): Dropping skb.
[  683.603796] blackhole_netdev_xmit(): Dropping skb.
[  683.603833] blackhole_netdev_xmit(): Dropping skb.
[  683.603867] blackhole_netdev_xmit(): Dropping skb.
[  994.772069] blackhole_netdev_xmit(): Dropping skb.
[  994.772151] blackhole_netdev_xmit(): Dropping skb.
[  994.772189] blackhole_netdev_xmit(): Dropping skb.
[  994.772233] blackhole_netdev_xmit(): Dropping skb.
[ 1012.934610] blackhole_netdev_xmit(): Dropping skb.
[ 1012.934669] blackhole_netdev_xmit(): Dropping skb.
[ 1012.934716] blackhole_netdev_xmit(): Dropping skb.
[ 1012.934744] blackhole_netdev_xmit(): Dropping skb.