6.0BETA3 panic in ip_output (vlan/RIP related?)

[Mark Tinguely]

> So it sounds like we need to figure out how the multicast code should 
> behave on interface removal -- I wonder what other operating systems do 
> here?  Do they simply invalidate current membership related with the 
> interface, or do they leave the multicast sockets in a state such that if 
> the interface comes back, the memberships are re-bound?

In the case of a non-local multicast sessions, the saved multicast socket
state would need to keep a timestamp of the last a multicast router IGMP
session probe to detect the possibility of session pruning.

--Mark Tinguely.