Re: [net-next:master 195/198] net/bridge/br_mdb.c:79:35: sparse: incompatible types in comparison expression (different address spaces)

[Cong Wang <amwang@redhat.com>]

On Sun, 2012-12-09 at 10:54 +0800, kbuild test robot wrote:
> tree:   git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git master
> head:   9ecb9aabaf634677c77af467f4e3028b09d7bcda
> commit: ee07c6e7a6f8a25c18f0a6b18152fbd7499245f6 [195/198] bridge: export multicast database via netlink
> 
> 
> sparse warnings:
> 
> + net/bridge/br_mdb.c:79:35: sparse: incompatible types in comparison expression (different address spaces)

Hi, Fengguang,

I am not sure if I understand this warning correctly. Does the following
patch fix it?

Thanks!

---------------->

diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
index 2528328..0bc0e13 100644
--- a/net/bridge/br_mdb.c
+++ b/net/bridge/br_mdb.c
@@ -77,7 +77,7 @@ static int br_mdb_fill_info(struct sk_buff *skb,
struct netlink_callback *cb,
                        }
 
                        for (pp = &mp->ports;
-                            (p = rcu_dereference(*pp)) != NULL;
+                            (p = rcu_dereference_protected(*pp, 1)) !=
NULL;
                              pp = &p->next) {
                                port = p->port;
                                if (port) {