Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751925Ab0LALKg (ORCPT ); Wed, 1 Dec 2010 06:10:36 -0500 Received: from mx1.redhat.com ([209.132.183.28]:24807 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751117Ab0LALKf (ORCPT ); Wed, 1 Dec 2010 06:10:35 -0500 From: Amerigo Wang To: linux-kernel@vger.kernel.org Cc: WANG Cong , "David S. Miller" , Alexey Kuznetsov , "Pekka Savola (ipv6)" , James Morris , Hideaki YOSHIFUJI , Patrick McHardy , netdev@vger.kernel.org Subject: [Patch] net: kill an RCU warning in inet_fill_link_af() Date: Wed, 1 Dec 2010 19:14:23 +0800 Message-Id: <1291202063-6239-1-git-send-email-amwang@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2659 Lines: 96 From: WANG Cong The latest net-next-2.6 triggers an RCU warning during boot, lockdep complains that in inet_fill_link_af() we call rcu_dereference_check() without rcu_read_lock() protection. This patch fixes it by replacing __in_dev_get_rcu() with in_dev_get(). Signed-off-by: WANG Cong --- diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index d9f71ba..73baed8 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -1258,31 +1258,36 @@ errout: static size_t inet_get_link_af_size(const struct net_device *dev) { - struct in_device *in_dev = __in_dev_get_rcu(dev); + struct in_device *in_dev = in_dev_get(dev); if (!in_dev) return 0; + in_dev_put(in_dev); return nla_total_size(IPV4_DEVCONF_MAX * 4); /* IFLA_INET_CONF */ } static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev) { - struct in_device *in_dev = __in_dev_get_rcu(dev); + struct in_device *in_dev = in_dev_get(dev); struct nlattr *nla; - int i; + int i, ret = 0; if (!in_dev) return -ENODATA; nla = nla_reserve(skb, IFLA_INET_CONF, IPV4_DEVCONF_MAX * 4); - if (nla == NULL) - return -EMSGSIZE; + if (nla == NULL) { + ret = -EMSGSIZE; + goto out; + } for (i = 0; i < IPV4_DEVCONF_MAX; i++) ((u32 *) nla_data(nla))[i] = in_dev->cnf.data[i]; - return 0; +out: + in_dev_put(in_dev); + return ret; } static const struct nla_policy inet_af_policy[IFLA_INET_MAX+1] = { @@ -1293,11 +1298,14 @@ static int inet_validate_link_af(const struct net_device *dev, const struct nlattr *nla) { struct nlattr *a, *tb[IFLA_INET_MAX+1]; + struct in_device *in_dev = in_dev_get(dev); int err, rem; - if (dev && !__in_dev_get_rcu(dev)) + if (dev && !in_dev) return -EAFNOSUPPORT; + in_dev_put(in_dev); + err = nla_parse_nested(tb, IFLA_INET_MAX, nla, inet_af_policy); if (err < 0) return err; @@ -1319,7 +1327,7 @@ static int inet_validate_link_af(const struct net_device *dev, static int inet_set_link_af(struct net_device *dev, const struct nlattr *nla) { - struct in_device *in_dev = __in_dev_get_rcu(dev); + struct in_device *in_dev = in_dev_get(dev); struct nlattr *a, *tb[IFLA_INET_MAX+1]; int rem; @@ -1334,6 +1342,7 @@ static int inet_set_link_af(struct net_device *dev, const struct nlattr *nla) ipv4_devconf_set(in_dev, nla_type(a), nla_get_u32(a)); } + in_dev_put(in_dev); return 0; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/