Subject: [PATCH net] Revert "tcp: must block bh in __inet_twsk_hashdance()"

From: Eric Dumazet <[email-masked]>
Date: Fri, 01 Dec 2017 15:28:44 -0800

From: Eric Dumazet <[email-masked]>

We had to disable BH _before_ calling __inet_twsk_hashdance() in commit
cfac7f836a71 ("tcp/dccp: block bh before arming time_wait timer").

This means we can revert 614bdd4d6e61 ("tcp: must block bh in
__inet_twsk_hashdance()").

Signed-off-by: Eric Dumazet <[email-masked]>
---
 net/ipv4/inet_timewait_sock.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/ipv4/inet_timewait_sock.c b/net/ipv4/inet_timewait_sock.c
index c690cd0d9b3f0af53c23b9a1ecc87be4098ae059..b563e0c46bac2362acccf38495546a8b6b726384 100644
--- a/net/ipv4/inet_timewait_sock.c
+++ b/net/ipv4/inet_timewait_sock.c
@@ -93,7 +93,7 @@ static void inet_twsk_add_bind_node(struct inet_timewait_sock *tw,
 }
 
 /*
- * Enter the time wait state.
+ * Enter the time wait state. This is called with locally disabled BH.
  * Essentially we whip up a timewait bucket, copy the relevant info into it
  * from the SK, and mess with hash chains and list linkage.
  */
@@ -111,7 +111,7 @@ void __inet_twsk_hashdance(struct inet_timewait_sock *tw, struct sock *sk,
 	 */
 	bhead = &hashinfo->bhash[inet_bhashfn(twsk_net(tw), inet->inet_num,
 			hashinfo->bhash_size)];
-	spin_lock_bh(&bhead->lock);
+	spin_lock(&bhead->lock);
 	tw->tw_tb = icsk->icsk_bind_hash;
 	WARN_ON(!icsk->icsk_bind_hash);
 	inet_twsk_add_bind_node(tw, &tw->tw_tb->owners);
@@ -137,7 +137,7 @@ void __inet_twsk_hashdance(struct inet_timewait_sock *tw, struct sock *sk,
 	if (__sk_nulls_del_node_init_rcu(sk))
 		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 
-	spin_unlock_bh(lock);
+	spin_unlock(lock);
 }
 EXPORT_SYMBOL_GPL(__inet_twsk_hashdance);