[PATCH] Prevent from potential dead lock for inet_listen_lock

[Gui Jianfeng <guijianfeng@cn.fujitsu.com>]

hashinfo->lhash_lock might be acquired by write_lock() in softirq, 
so using read_lock() here isn't safe, just substitudes by read_lock_bh().

Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
---
 include/net/inet_hashtables.h |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/net/inet_hashtables.h b/include/net/inet_hashtables.h
index 97dc35a..2818c8a 100644
--- a/include/net/inet_hashtables.h
+++ b/include/net/inet_hashtables.h
@@ -254,9 +254,9 @@ extern void inet_listen_wlock(struct inet_hashinfo *hashinfo);
 static inline void inet_listen_lock(struct inet_hashinfo *hashinfo)
 {
 	/* read_lock synchronizes to candidates to writers */
-	read_lock(&hashinfo->lhash_lock);
+	read_lock_bh(&hashinfo->lhash_lock);
 	atomic_inc(&hashinfo->lhash_users);
-	read_unlock(&hashinfo->lhash_lock);
+	read_unlock_bh(&hashinfo->lhash_lock);
 }
 
 static inline void inet_listen_unlock(struct inet_hashinfo *hashinfo)
-- 
1.5.3