[IPV6]: Temp fix for ipv6 link-local address problem.

Make sure loopback_dev, if up, has the ipv6 bits
for it setup before the addrconf netdev notifier
is registered.
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/addrconf.c

@@ -3387,6 +3387,29 @@ int unregister_inet6addr_notifier(struct notifier_block *nb)
 
 void __init addrconf_init(void)
 {
+	/* The addrconf netdev notifier requires that loopback_dev
+	 * has it's ipv6 private information allocated and setup
+	 * before it can bring up and give link-local addresses
+	 * to other devices which are up.
+	 *
+	 * Unfortunately, loopback_dev is not necessarily the first
+	 * entry in the global dev_base list of net devices.  In fact,
+	 * it is likely to be the very last entry on that list.
+	 * So this causes the notifier registry below to try and
+	 * give link-local addresses to all devices besides loopback_dev
+	 * first, then loopback_dev, which cases all the non-loopback_dev
+	 * devices to fail to get a link-local address.
+	 *
+	 * So, as a temporary fix, register loopback_dev first by hand.
+	 * Longer term, all of the dependencies ipv6 has upon the loopback
+	 * device and it being up should be removed.
+	 */
+	rtnl_lock();
+	addrconf_notify(&ipv6_dev_notf, NETDEV_REGISTER, &loopback_dev);
+	if (loopback_dev.flags & IFF_UP)
+		addrconf_notify(&ipv6_dev_notf, NETDEV_UP, &loopback_dev);
+	rtnl_unlock();
+
 	register_netdevice_notifier(&ipv6_dev_notf);
 
 #ifdef CONFIG_IPV6_PRIVACY