[    2.669154] ip (279) used greatest stack depth: 12352 bytes left
[   23.767320] ip (2185) used greatest stack depth: 12336 bytes left
[  639.149464] ip (25587) used greatest stack depth: 12200 bytes left
[ 1058.080778] blackhole_netdev_xmit(): Dropping skb.
[ 1058.080850] blackhole_netdev_xmit(): Dropping skb.
[ 1058.080885] blackhole_netdev_xmit(): Dropping skb.
[ 1058.080918] blackhole_netdev_xmit(): Dropping skb.
[ 1228.778482] blackhole_netdev_xmit(): Dropping skb.
[ 1228.778556] blackhole_netdev_xmit(): Dropping skb.
[ 1228.778610] blackhole_netdev_xmit(): Dropping skb.
[ 1228.778661] blackhole_netdev_xmit(): Dropping skb.