Dead loop on virutal device.

Since I'm using a 2.4.17 (upgrade from a 2.2.16), I get this message:

Dead loop on virtual device tun1, fix it urgently!

Sometimes it's there a short time between them, other times a long time.

I got no idea what's causing them.

I tried looking at the source and it says something about recursion and something about SMP. This is not an SMP box.

The device in question is a tunnel device, it does ipv6 over ipv4. Most traffic goes thru that one. It's the only one that generates that message.

It says to fix it urgently, but I don't know how, and it seems to work fine otherwise.

Do you know what is wrong and how I can fix this?

Kurt