[Patch net-next] ipv6: statically link register_inet6addr_notifier()

[Patch net-next] ipv6: statically link register_inet6addr_notifier()

[Cong Wang]

From: Cong Wang <amwang@redhat.com>

Tomas reported the following build error:

net/built-in.o: In function `ieee80211_unregister_hw':
(.text+0x10f0e1): undefined reference to `unregister_inet6addr_notifier'
net/built-in.o: In function `ieee80211_register_hw':
(.text+0x10f610): undefined reference to `register_inet6addr_notifier'
make: *** [vmlinux] Error 1

when built IPv6 as a module.

So we have to statically link these symbols.

Reported-by: Tomas Melin <tomas.melin@iki.fi>
Cc: Tomas Melin <tomas.melin@iki.fi>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: YOSHIFUJI Hidaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Cong Wang <amwang@redhat.com>

---
diff --git a/include/net/addrconf.h b/include/net/addrconf.h
index 40be2a0..84a6440 100644
--- a/include/net/addrconf.h
+++ b/include/net/addrconf.h
@@ -199,6 +199,7 @@ extern bool ipv6_chk_acast_addr(struct net *net, struct net_device *dev,
 /* Device notifier */
 extern int register_inet6addr_notifier(struct notifier_block *nb);
 extern int unregister_inet6addr_notifier(struct notifier_block *nb);
+extern int inet6addr_notifier_call_chain(unsigned long val, void *v);
 
 extern void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
 					 struct ipv6_devconf *devconf);
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 28b61e8..d1ab6ab 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -169,8 +169,6 @@ static void inet6_prefix_notify(int event, struct inet6_dev *idev,
 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
 			       struct net_device *dev);
 
-static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
-
 static struct ipv6_devconf ipv6_devconf __read_mostly = {
 	.forwarding		= 0,
 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
@@ -910,7 +908,7 @@ out2:
 	rcu_read_unlock_bh();
 
 	if (likely(err == 0))
-		atomic_notifier_call_chain(&inet6addr_chain, NETDEV_UP, ifa);
+		inet6addr_notifier_call_chain(NETDEV_UP, ifa);
 	else {
 		kfree(ifa);
 		ifa = ERR_PTR(err);
@@ -1000,7 +998,7 @@ static void ipv6_del_addr(struct inet6_ifaddr *ifp)
 
 	ipv6_ifa_notify(RTM_DELADDR, ifp);
 
-	atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifp);
+	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
 
 	/*
 	 * Purge or update corresponding prefix
@@ -3087,7 +3085,7 @@ static int addrconf_ifdown(struct net_device *dev, int how)
 
 		if (state != INET6_IFADDR_STATE_DEAD) {
 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
-			atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifa);
+			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
 		}
 		in6_ifa_put(ifa);
 
@@ -5054,22 +5052,6 @@ static struct pernet_operations addrconf_ops = {
 	.exit = addrconf_exit_net,
 };
 
-/*
- *      Device notifier
- */
-
-int register_inet6addr_notifier(struct notifier_block *nb)
-{
-	return atomic_notifier_chain_register(&inet6addr_chain, nb);
-}
-EXPORT_SYMBOL(register_inet6addr_notifier);
-
-int unregister_inet6addr_notifier(struct notifier_block *nb)
-{
-	return atomic_notifier_chain_unregister(&inet6addr_chain, nb);
-}
-EXPORT_SYMBOL(unregister_inet6addr_notifier);
-
 static struct rtnl_af_ops inet6_ops = {
 	.family		  = AF_INET6,
 	.fill_link_af	  = inet6_fill_link_af,
diff --git a/net/ipv6/addrconf_core.c b/net/ipv6/addrconf_core.c
index d051e5f..7210456 100644
--- a/net/ipv6/addrconf_core.c
+++ b/net/ipv6/addrconf_core.c
@@ -78,3 +78,22 @@ int __ipv6_addr_type(const struct in6_addr *addr)
 }
 EXPORT_SYMBOL(__ipv6_addr_type);
 
+static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
+
+int register_inet6addr_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_register(&inet6addr_chain, nb);
+}
+EXPORT_SYMBOL(register_inet6addr_notifier);
+
+int unregister_inet6addr_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_unregister(&inet6addr_chain, nb);
+}
+EXPORT_SYMBOL(unregister_inet6addr_notifier);
+
+int inet6addr_notifier_call_chain(unsigned long val, void *v)
+{
+	return atomic_notifier_call_chain(&inet6addr_chain, val, v);
+}
+EXPORT_SYMBOL(inet6addr_notifier_call_chain);

Re: [Patch net-next] ipv6: statically link register_inet6addr_notifier()

[David Miller]

From: Cong Wang <amwang@redhat.com>
Date: Sun, 14 Apr 2013 23:18:43 +0800

> From: Cong Wang <amwang@redhat.com>
> 
> Tomas reported the following build error:
> 
> net/built-in.o: In function `ieee80211_unregister_hw':
> (.text+0x10f0e1): undefined reference to `unregister_inet6addr_notifier'
> net/built-in.o: In function `ieee80211_register_hw':
> (.text+0x10f610): undefined reference to `register_inet6addr_notifier'
> make: *** [vmlinux] Error 1
> 
> when built IPv6 as a module.
> 
> So we have to statically link these symbols.
> 
> Reported-by: Tomas Melin <tomas.melin@iki.fi>
> Cc: Tomas Melin <tomas.melin@iki.fi>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: YOSHIFUJI Hidaki <yoshfuji@linux-ipv6.org>
> Signed-off-by: Cong Wang <amwang@redhat.com>

This bug exists in 'net' so that's where I'm applying this.

Re: [Patch net-next] ipv6: statically link register_inet6addr_notifier()

[Tomas Melin]

On Sun, Apr 14, 2013 at 6:18 PM, Cong Wang <amwang@redhat.com> wrote:
> From: Cong Wang <amwang@redhat.com>
>
> Tomas reported the following build error:
>
> net/built-in.o: In function `ieee80211_unregister_hw':
> (.text+0x10f0e1): undefined reference to `unregister_inet6addr_notifier'
> net/built-in.o: In function `ieee80211_register_hw':
> (.text+0x10f610): undefined reference to `register_inet6addr_notifier'
> make: *** [vmlinux] Error 1
>
> when built IPv6 as a module.
>
> So we have to statically link these symbols.
>
> Reported-by: Tomas Melin <tomas.melin@iki.fi>
> Cc: Tomas Melin <tomas.melin@iki.fi>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: YOSHIFUJI Hidaki <yoshfuji@linux-ipv6.org>
> Signed-off-by: Cong Wang <amwang@redhat.com>


This fixes the issue. Added Johannes Berg for information.

thanks,
Tomas




>
> ---
> diff --git a/include/net/addrconf.h b/include/net/addrconf.h
> index 40be2a0..84a6440 100644
> --- a/include/net/addrconf.h
> +++ b/include/net/addrconf.h
> @@ -199,6 +199,7 @@ extern bool ipv6_chk_acast_addr(struct net *net, struct net_device *dev,
>  /* Device notifier */
>  extern int register_inet6addr_notifier(struct notifier_block *nb);
>  extern int unregister_inet6addr_notifier(struct notifier_block *nb);
> +extern int inet6addr_notifier_call_chain(unsigned long val, void *v);
>
>  extern void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
>                                          struct ipv6_devconf *devconf);
> diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
> index 28b61e8..d1ab6ab 100644
> --- a/net/ipv6/addrconf.c
> +++ b/net/ipv6/addrconf.c
> @@ -169,8 +169,6 @@ static void inet6_prefix_notify(int event, struct inet6_dev *idev,
>  static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
>                                struct net_device *dev);
>
> -static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
> -
>  static struct ipv6_devconf ipv6_devconf __read_mostly = {
>         .forwarding             = 0,
>         .hop_limit              = IPV6_DEFAULT_HOPLIMIT,
> @@ -910,7 +908,7 @@ out2:
>         rcu_read_unlock_bh();
>
>         if (likely(err == 0))
> -               atomic_notifier_call_chain(&inet6addr_chain, NETDEV_UP, ifa);
> +               inet6addr_notifier_call_chain(NETDEV_UP, ifa);
>         else {
>                 kfree(ifa);
>                 ifa = ERR_PTR(err);
> @@ -1000,7 +998,7 @@ static void ipv6_del_addr(struct inet6_ifaddr *ifp)
>
>         ipv6_ifa_notify(RTM_DELADDR, ifp);
>
> -       atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifp);
> +       inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
>
>         /*
>          * Purge or update corresponding prefix
> @@ -3087,7 +3085,7 @@ static int addrconf_ifdown(struct net_device *dev, int how)
>
>                 if (state != INET6_IFADDR_STATE_DEAD) {
>                         __ipv6_ifa_notify(RTM_DELADDR, ifa);
> -                       atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifa);
> +                       inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
>                 }
>                 in6_ifa_put(ifa);
>
> @@ -5054,22 +5052,6 @@ static struct pernet_operations addrconf_ops = {
>         .exit = addrconf_exit_net,
>  };
>
> -/*
> - *      Device notifier
> - */
> -
> -int register_inet6addr_notifier(struct notifier_block *nb)
> -{
> -       return atomic_notifier_chain_register(&inet6addr_chain, nb);
> -}
> -EXPORT_SYMBOL(register_inet6addr_notifier);
> -
> -int unregister_inet6addr_notifier(struct notifier_block *nb)
> -{
> -       return atomic_notifier_chain_unregister(&inet6addr_chain, nb);
> -}
> -EXPORT_SYMBOL(unregister_inet6addr_notifier);
> -
>  static struct rtnl_af_ops inet6_ops = {
>         .family           = AF_INET6,
>         .fill_link_af     = inet6_fill_link_af,
> diff --git a/net/ipv6/addrconf_core.c b/net/ipv6/addrconf_core.c
> index d051e5f..7210456 100644
> --- a/net/ipv6/addrconf_core.c
> +++ b/net/ipv6/addrconf_core.c
> @@ -78,3 +78,22 @@ int __ipv6_addr_type(const struct in6_addr *addr)
>  }
>  EXPORT_SYMBOL(__ipv6_addr_type);
>
> +static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
> +
> +int register_inet6addr_notifier(struct notifier_block *nb)
> +{
> +       return atomic_notifier_chain_register(&inet6addr_chain, nb);
> +}
> +EXPORT_SYMBOL(register_inet6addr_notifier);
> +
> +int unregister_inet6addr_notifier(struct notifier_block *nb)
> +{
> +       return atomic_notifier_chain_unregister(&inet6addr_chain, nb);
> +}
> +EXPORT_SYMBOL(unregister_inet6addr_notifier);
> +
> +int inet6addr_notifier_call_chain(unsigned long val, void *v)
> +{
> +       return atomic_notifier_call_chain(&inet6addr_chain, val, v);
> +}
> +EXPORT_SYMBOL(inet6addr_notifier_call_chain);

Re: [Patch net-next] ipv6: statically link register_inet6addr_notifier()

[Johannes Berg]

On Mon, 2013-04-15 at 13:40 +0300, Tomas Melin wrote:
> On Sun, Apr 14, 2013 at 6:18 PM, Cong Wang <amwang@redhat.com> wrote:
> > From: Cong Wang <amwang@redhat.com>
> >
> > Tomas reported the following build error:
> >
> > net/built-in.o: In function `ieee80211_unregister_hw':
> > (.text+0x10f0e1): undefined reference to `unregister_inet6addr_notifier'
> > net/built-in.o: In function `ieee80211_register_hw':
> > (.text+0x10f610): undefined reference to `register_inet6addr_notifier'
> > make: *** [vmlinux] Error 1
> >
> > when built IPv6 as a module.
> >
> > So we have to statically link these symbols.
> >
> > Reported-by: Tomas Melin <tomas.melin@iki.fi>
> > Cc: Tomas Melin <tomas.melin@iki.fi>
> > Cc: "David S. Miller" <davem@davemloft.net>
> > Cc: YOSHIFUJI Hidaki <yoshfuji@linux-ipv6.org>
> > Signed-off-by: Cong Wang <amwang@redhat.com>
> 
> 
> This fixes the issue. Added Johannes Berg for information.

> > +++ b/net/ipv6/addrconf.c

> > -EXPORT_SYMBOL(register_inet6addr_notifier);

> > +++ b/net/ipv6/addrconf_core.c
> > @@ -78,3 +78,22 @@ int __ipv6_addr_type(const struct in6_addr *addr)
> >  }
> >  EXPORT_SYMBOL(__ipv6_addr_type);
> >
> > +static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
> > +
> > +int register_inet6addr_notifier(struct notifier_block *nb)
> > +{
> > +       return atomic_notifier_chain_register(&inet6addr_chain, nb);
> > +}
> > +EXPORT_SYMBOL(register_inet6addr_notifier);

That works for me, but it seems pretty pointless to have this API?
Anyway, let me know if you want to apply this patch, then I'll drop mine
and also remove the ifdefs from mac80211.

johannes

Re: [Patch net-next] ipv6: statically link register_inet6addr_notifier()

[Johannes Berg]

On Mon, 2013-04-15 at 13:09 +0200, Johannes Berg wrote:

> That works for me, but it seems pretty pointless to have this API?
> Anyway, let me know if you want to apply this patch, then I'll drop mine
> and also remove the ifdefs from mac80211.

Oh, I misunderstood the patch. This actually makes Tomas's configuration
possible and work, I guess.

Btw, if this is what you want to do then we can also fix a number of
drivers to not have special Kconfig symbols for IPv6 etc.

johannes