From: Eric Dumazet <edumazet@google.com>
Date: Fri, 1 Dec 2017 15:28:44 -0800
Subject: Revert "tcp: must block bh in __inet_twsk_hashdance()"
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Patch-mainline: v4.15-rc3
Git-commit: e599ea1410c3a2f55716f9c309587235cca32025
References: bsc#1076830

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 <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Michal Kubecek <mkubecek@suse.cz>

---
 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 f8aff2c71cde..659434688f48 100644
--- a/net/ipv4/inet_timewait_sock.c
+++ b/net/ipv4/inet_timewait_sock.c
@@ -94,7 +94,7 @@ 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.
  */
@@ -112,7 +112,7 @@ 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);
@@ -138,7 +138,7 @@ 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);
 
-- 
2.16.2