[patch 05/26] Fix some cases of missed IPV6 DAD

[Greg KH <gregkh@suse.de>]

[-- Attachment #1: fix-some-cases-of-missed-ipv6-dad.patch --]
[-- Type: text/plain, Size: 2252 bytes --]

2.6.22-stable review patch.  If anyone has any objections, please let us
know.

------------------
From: Mitsuru Chinen <mitch@linux.vnet.ibm.com>

changeset 0fcace22d38ce9216f5ba52f929a99d284aa7e49 from mainline

To judge the timing for DAD, netif_carrier_ok() is used. However,
there is a possibility that dev->qdisc stays noop_qdisc even if
netif_carrier_ok() returns true. In that case, DAD NS is not sent out.
We need to defer the IPv6 device initialization until a valid qdisc
is specified.

Signed-off-by: Mitsuru Chinen <mitch@linux.vnet.ibm.com>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 net/ipv6/addrconf.c |   13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -73,6 +73,7 @@
 #include <net/tcp.h>
 #include <net/ip.h>
 #include <net/netlink.h>
+#include <net/pkt_sched.h>
 #include <linux/if_tunnel.h>
 #include <linux/rtnetlink.h>
 
@@ -212,6 +213,12 @@ static struct ipv6_devconf ipv6_devconf_
 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
 const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
 
+/* Check if a valid qdisc is available */
+static inline int addrconf_qdisc_ok(struct net_device *dev)
+{
+	return (dev->qdisc != &noop_qdisc);
+}
+
 static void addrconf_del_timer(struct inet6_ifaddr *ifp)
 {
 	if (del_timer(&ifp->timer))
@@ -376,7 +383,7 @@ static struct inet6_dev * ipv6_add_dev(s
 	}
 #endif
 
-	if (netif_running(dev) && netif_carrier_ok(dev))
+	if (netif_running(dev) && addrconf_qdisc_ok(dev))
 		ndev->if_flags |= IF_READY;
 
 	ipv6_mc_init_dev(ndev);
@@ -2269,7 +2276,7 @@ static int addrconf_notify(struct notifi
 	case NETDEV_UP:
 	case NETDEV_CHANGE:
 		if (event == NETDEV_UP) {
-			if (!netif_carrier_ok(dev)) {
+			if (!addrconf_qdisc_ok(dev)) {
 				/* device is not ready yet. */
 				printk(KERN_INFO
 					"ADDRCONF(NETDEV_UP): %s: "
@@ -2281,7 +2288,7 @@ static int addrconf_notify(struct notifi
 			if (idev)
 				idev->if_flags |= IF_READY;
 		} else {
-			if (!netif_carrier_ok(dev)) {
+			if (!addrconf_qdisc_ok(dev)) {
 				/* device is still not ready. */
 				break;
 			}

--