Subject: Re: [PATCH 1/2] IPv6: keep permanent addresses on admin down

From: Brian Haley <[email-masked]>
Date: Tue, 09 Feb 2010 09:40:11 -0500

Stephen Hemminger wrote:
> @@ -2686,18 +2687,30 @@ static int addrconf_ifdown(struct net_de
>  		write_lock_bh(&idev->lock);
>  	}
>  #endif
> -	while ((ifa = idev->addr_list) != NULL) {
> -		idev->addr_list = ifa->if_next;
> -		ifa->if_next = NULL;
> -		ifa->dead = 1;
> -		addrconf_del_timer(ifa);
> -		write_unlock_bh(&idev->lock);
> -
> -		__ipv6_ifa_notify(RTM_DELADDR, ifa);
> -		atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifa);
> -		in6_ifa_put(ifa);
> +	bifa = &idev->addr_list;
> +	while ((ifa = *bifa) != NULL) {
> +		if (how == 0 && (ifa->flags&IFA_F_PERMANENT)) {
> +			/* Retain permanent address on admin down */
> +			bifa = &ifa->if_next;
> +
> +			/* Restart DAD if needed when link comes back up */
> +			if ( !((dev->flags&(IFF_NOARP|IFF_LOOPBACK)) ||
> +			       idev->cnf.accept_dad <= 0 ||
> +			       (ifa->flags & IFA_F_NODAD)))
> +				ifa->flags |= IFA_F_TENTATIVE;
> +		} else {
> +			*bifa = ifa->if_next;
> +			ifa->if_next = NULL;
> +
> +			ifa->dead = 1;
> +			write_unlock_bh(&idev->lock);
> +
> +			__ipv6_ifa_notify(RTM_DELADDR, ifa);
> +			atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifa);
> +			in6_ifa_put(ifa);
>  
> -		write_lock_bh(&idev->lock);
> +			write_lock_bh(&idev->lock);
> +		}

What about addrconf_del_timer()?  It didn't seem to make it to this else{} from
the original.

-Brian