On Tue, 29 Aug 2006, David Miller wrote:

From: YOSHIFUJI Hideaki <redacted>
Date: Tue, 29 Aug 2006 18:34:26 +0900 (JST)

quoted

Further analysis is needed, but one idea is to skip
addrconf_dev_config() if !(dev->flags & IFF_MULTICAST).

Yes, it is logical because without multicast IPV6 cannot
work correctly.

But from another perspective (I assume these bridged Xen devices use
ARPHRD_ETHER, do they?) a device with ARPHRD_ETHER and cleared
IFF_MULTICAST flag seems potentially problematic.  How many other
things break over such a device?

It's not obvious that IFF_MULTICAST is good enough.  IMHO, you should 
be able to run addrconf on non-multicast interfaces as well (e.g., 
point-to-point interfaces, tunnels in particular).

It seems that current code already excludes IFF_NOARP interfaces 
though.

-- 
Pekka Savola                 "You each name yourselves king, yet the
Netcore Oy                    kingdom bleeds."
Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings