[    2.054839] ip (247) used greatest stack depth: 12328 bytes left
[  768.471271] blackhole_netdev_xmit(): Dropping skb.
[  768.471336] blackhole_netdev_xmit(): Dropping skb.
[  768.471368] blackhole_netdev_xmit(): Dropping skb.
[  768.471399] blackhole_netdev_xmit(): Dropping skb.
[  955.492312] ip (24815) used greatest stack depth: 12304 bytes left