From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1032026Ab2I1UXK (ORCPT ); Fri, 28 Sep 2012 16:23:10 -0400 Received: from mail-pa0-f46.google.com ([209.85.220.46]:61998 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031263Ab2I1UXB (ORCPT ); Fri, 28 Sep 2012 16:23:01 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, Dmitry Kozlov , "David S. Miller" Subject: [ 028/218] l2tp: avoid to use synchronize_rcu in tunnel free function Date: Fri, 28 Sep 2012 13:14:05 -0700 Message-Id: <20120928201504.615953365@linuxfoundation.org> X-Mailer: git-send-email 1.7.12.1.428.g652398a In-Reply-To: <20120928201501.208384923@linuxfoundation.org> References: <20120928201501.208384923@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.4-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 --- net/l2tp/l2tp_core.c | 3 +-- net/l2tp/l2tp_core.h | 1 + 2 files changed, 2 insertions(+), 2 deletions(-) --- a/net/l2tp/l2tp_core.c +++ b/net/l2tp/l2tp_core.c @@ -1253,11 +1253,10 @@ static void l2tp_tunnel_free(struct l2tp /* 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 --- 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,