From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754282Ab2IQBLY (ORCPT ); Sun, 16 Sep 2012 21:11:24 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:33726 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753856Ab2IQAuj (ORCPT ); Sun, 16 Sep 2012 20:50:39 -0400 Message-Id: <20120917003636.318896221@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Mon, 17 Sep 2012 01:37:38 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, "xeb@mail.ru" , "David S. Miller" Subject: [ 073/135] l2tp: avoid to use synchronize_rcu in tunnel free function In-Reply-To: <20120917003625.784119135@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:21c:bfff:fe03:f805 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: "xeb@mail.ru" [ Upstream commit 99469c32f79a32d8481f87be0d3c66dad286f4ec ] Avoid to use synchronize_rcu in l2tp_tunnel_free because context may be atomic. Signed-off-by: Dmitry Kozlov Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/l2tp/l2tp_core.c | 3 +-- net/l2tp/l2tp_core.h | 1 + 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c index 89ff8c6..7501b22 100644 --- a/net/l2tp/l2tp_core.c +++ b/net/l2tp/l2tp_core.c @@ -1253,11 +1253,10 @@ static void l2tp_tunnel_free(struct l2tp_tunnel *tunnel) /* Remove from tunnel list */ spin_lock_bh(&pn->l2tp_tunnel_list_lock); list_del_rcu(&tunnel->list); + kfree_rcu(tunnel, rcu); spin_unlock_bh(&pn->l2tp_tunnel_list_lock); - synchronize_rcu(); atomic_dec(&l2tp_tunnel_count); - kfree(tunnel); } /* Create a socket for the tunnel, if one isn't set up by diff --git a/net/l2tp/l2tp_core.h b/net/l2tp/l2tp_core.h index a16a48e..4393794 100644 --- a/net/l2tp/l2tp_core.h +++ b/net/l2tp/l2tp_core.h @@ -157,6 +157,7 @@ struct l2tp_tunnel_cfg { struct l2tp_tunnel { int magic; /* Should be L2TP_TUNNEL_MAGIC */ + struct rcu_head rcu; rwlock_t hlist_lock; /* protect session_hlist */ struct hlist_head session_hlist[L2TP_HASH_SIZE]; /* hashed list of sessions,