[    1.677994] ip (241) used greatest stack depth: 12352 bytes left
[    2.079312] ip (275) used greatest stack depth: 12320 bytes left
[   12.777850] ip (1399) used greatest stack depth: 12272 bytes left
[  323.304465] ip (6177) used greatest stack depth: 12176 bytes left
[ 1051.681549] blackhole_netdev_xmit(): Dropping skb.
[ 1051.681630] blackhole_netdev_xmit(): Dropping skb.
[ 1051.681692] blackhole_netdev_xmit(): Dropping skb.
[ 1051.681761] blackhole_netdev_xmit(): Dropping skb.
[ 1060.539219] blackhole_netdev_xmit(): Dropping skb.
[ 1060.539268] blackhole_netdev_xmit(): Dropping skb.
[ 1060.539300] blackhole_netdev_xmit(): Dropping skb.
[ 1060.539327] blackhole_netdev_xmit(): Dropping skb.