From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: [PATCH 03/12] IPv6: addrconf notify when address is unavailable Date: Tue, 02 Mar 2010 15:32:46 -0800 Message-ID: <20100302234003.046022988@vyatta.com> References: <20100302233243.259794027@vyatta.com> Cc: netdev@vger.kernel.org To: "David S. Miller" , Hideaki YOSHIFUJI Return-path: Received: from suva.vyatta.com ([76.74.103.44]:58935 "EHLO suva.vyatta.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756126Ab0CBXqy (ORCPT ); Tue, 2 Mar 2010 18:46:54 -0500 Content-Disposition: inline; filename=addrconf-anycast-notify.patch Sender: netdev-owner@vger.kernel.org List-ID: My recent change in net-next to retain permanent addresses caused regression. Device refcount would not go to zero when device was unregistered because left over anycast reference would hold ipv6 dev reference which would hold device references... The correct procedure is to call notify chain when address is no longer available for use. When interface comes back DAD timer will notify back that address is available. Also, link local addresses should be purged when interface is brought down. The address might be changed. Signed-off-by: Stephen Hemminger --- net/ipv6/addrconf.c | 37 ++++++++++++++++++++++--------------- 1 file changed, 22 insertions(+), 15 deletions(-) --- a/net/ipv6/addrconf.c 2010-02-27 08:56:23.955450341 -0800 +++ b/net/ipv6/addrconf.c 2010-02-27 08:57:02.271199959 -0800 @@ -2649,11 +2649,11 @@ static int addrconf_ifdown(struct net_de write_lock_bh(&addrconf_hash_lock); while ((ifa = *bifa) != NULL) { if (ifa->idev == idev && - (how || !(ifa->flags&IFA_F_PERMANENT))) { + (how || !(ifa->flags&IFA_F_PERMANENT) || + ipv6_addr_type(&ifa->addr) & IPV6_ADDR_LINKLOCAL)) { *bifa = ifa->lst_next; ifa->lst_next = NULL; - addrconf_del_timer(ifa); - in6_ifa_put(ifa); + __in6_ifa_put(ifa); continue; } bifa = &ifa->lst_next; @@ -2691,28 +2691,40 @@ static int addrconf_ifdown(struct net_de #endif bifa = &idev->addr_list; while ((ifa = *bifa) != NULL) { - if (how == 0 && (ifa->flags&IFA_F_PERMANENT)) { - /* Retain permanent address on admin down */ + addrconf_del_timer(ifa); + + /* If just doing link down, and address is permanent + and not link-local, then retain it. */ + if (how == 0 && + (ifa->flags&IFA_F_PERMANENT) && + !(ipv6_addr_type(&ifa->addr) & IPV6_ADDR_LINKLOCAL)) { 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; + /* If not doing DAD on this address, just keep it. */ + if ((dev->flags&(IFF_NOARP|IFF_LOOPBACK)) || + idev->cnf.accept_dad <= 0 || + (ifa->flags & IFA_F_NODAD)) + continue; + + /* If it was tentative already, no need to notify */ + if (ifa->flags & IFA_F_TENTATIVE) + continue; + + /* Flag it for later restoration when link comes up */ + ifa->flags |= IFA_F_TENTATIVE; + in6_ifa_hold(ifa); } else { *bifa = ifa->if_next; ifa->if_next = NULL; - ifa->dead = 1; - write_unlock_bh(&idev->lock); + } + write_unlock_bh(&idev->lock); - __ipv6_ifa_notify(RTM_DELADDR, ifa); - atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifa); - in6_ifa_put(ifa); + __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); } write_unlock_bh(&idev->lock); --