[    2.951600] ip (281) used greatest stack depth: 12360 bytes left
[    3.010604] ip (286) used greatest stack depth: 12344 bytes left
[   26.406636] ip (2141) used greatest stack depth: 12304 bytes left
[   31.066705] ip (2387) used greatest stack depth: 12064 bytes left
[  660.273402] blackhole_netdev_xmit(): Dropping skb.
[  660.273460] blackhole_netdev_xmit(): Dropping skb.
[  660.273491] blackhole_netdev_xmit(): Dropping skb.
[  660.273517] blackhole_netdev_xmit(): Dropping skb.
[ 1185.327744] blackhole_netdev_xmit(): Dropping skb.
[ 1185.327818] blackhole_netdev_xmit(): Dropping skb.
[ 1185.327847] blackhole_netdev_xmit(): Dropping skb.
[ 1185.327878] blackhole_netdev_xmit(): Dropping skb.