Re: [Vlan-devel] Some more questions on multicast & VLAN.

[Gleb Natapov <gleb@xxxxxxxxxxx>]

On Tue, Oct 10, 2000 at 08:56:45AM -0700, Ben Greear wrote:
>
[...]
> You mentioned that there was a race condition when using SMP, could you 
> explain
> that one a bit more?  We could probably put a lock around it if we need to, in
> order to make it safe.

 Not a race condition, but deadlock. Look at linux/net/core/dev_mcast.c. VLAN 
set_multicast_list()
function is called from dev_mc_upload() while holding dev_mc_lock. When you try 
to add or delete
MC address to/from underlying device from your set_multicast_list() you call 
dev_mc_{delete,add} 
and they also try to grab the same lock, oops deadlock ;)

--
                        Gleb.