From patchwork Mon Jun 19 18:30:33 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Willy Tarreau X-Patchwork-Id: 105909 Delivered-To: patch@linaro.org Received: by 10.140.91.2 with SMTP id y2csp1009633qgd; Mon, 19 Jun 2017 11:37:41 -0700 (PDT) X-Received: by 10.99.7.129 with SMTP id 123mr27587588pgh.171.1497897461408; Mon, 19 Jun 2017 11:37:41 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1497897461; cv=none; d=google.com; s=arc-20160816; b=uvs3gbqXLZxtGFz37qIn0uQg6hi8DckJvIPzyIAY2z5bj4IRUdLWcHtVvrwMjbo2af j5j8TLIMJdoMdT0ko+BwAjn635g4npfZoITtAXuaNEPvK3P2UfHFZcojpaKM2RizG7Xy VSP+jBmz5UPRcOAm90clnXifKYNS+bdpRu9ZjOuEQhEIH3GAlx8KyGPw895qJCzC1V46 7qQhhjVGq7ZABI4fKBD8ijOfWKXdoVJK1SMWVs8njxIqp6SgNIN2g8CKmnUJeaB1MkTG t3fIp3cMnW9swbXgsiy86M/fW+L8WSfTMX2HILQyjoORn/NjyWheJp1SUQIslJKfzRLx d5Dw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=KTtEYdmaOWQh9h4kEj4U/R2XalVrBsSDOzkgqt1MR/s=; b=nTHOa2AJJyIhwFta9Ws7qcTvsAj7wLy0QRUf8mCgJ5INydOsjQ2WzD+gabL1ON7x00 ZJAu9CnqUXgKUlAYN2s9h4Rc/FMO9C31f1raRrNO/96pCEbMuhK5P8wyQUnJFwT8SteN Am0eWkyVGcR7NJpLslC2B4vYvwww1iBHM7EqBhWU7LFqoeln6VnM4+pmEy4eGnrtu3v8 BJj4pzgo9WCJ+wt8sBDHZn9ymnhubQYuOqKVA3fSINQjx/yn7s8askU4NQjXMiKy/Pou 57opHxUsPJRAs3soeMGshLmIGAE0H0OTZbRy2nRQwsCzR7t01EhudtJwQAb6c+IpNPYt MhRg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id m1si9640186plb.301.2017.06.19.11.37.41; Mon, 19 Jun 2017 11:37:41 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753693AbdFSShf (ORCPT + 25 others); Mon, 19 Jun 2017 14:37:35 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:52519 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753614AbdFSShd (ORCPT ); Mon, 19 Jun 2017 14:37:33 -0400 Received: (from willy@localhost) by pcw.home.local (8.15.2/8.15.2/Submit) id v5JIXT57015000; Mon, 19 Jun 2017 20:33:29 +0200 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: Kefeng Wang , "David S . Miller" , Willy Tarreau Subject: [PATCH 3.10 134/268] ipv6: addrconf: Avoid addrconf_disable_change() using RCU read-side lock Date: Mon, 19 Jun 2017 20:30:33 +0200 Message-Id: <1497897167-14556-135-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1497897167-14556-1-git-send-email-w@1wt.eu> References: <1497897167-14556-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Kefeng Wang commit 03e4deff4987f79c34112c5ba4eb195d4f9382b0 upstream. Just like commit 4acd4945cd1e ("ipv6: addrconf: Avoid calling netdevice notifiers with RCU read-side lock"), it is unnecessary to make addrconf_disable_change() use RCU iteration over the netdev list, since it already holds the RTNL lock, or we may meet Illegal context switch in RCU read-side critical section. Signed-off-by: Kefeng Wang Signed-off-by: David S. Miller Signed-off-by: Willy Tarreau --- net/ipv6/addrconf.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) -- 2.8.0.rc2.1.gbe9624a diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index a3e2c34..9c4aa2e 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -4768,8 +4768,7 @@ static void addrconf_disable_change(struct net *net, __s32 newf) struct net_device *dev; struct inet6_dev *idev; - rcu_read_lock(); - for_each_netdev_rcu(net, dev) { + for_each_netdev(net, dev) { idev = __in6_dev_get(dev); if (idev) { int changed = (!idev->cnf.disable_ipv6) ^ (!newf); @@ -4778,7 +4777,6 @@ static void addrconf_disable_change(struct net *net, __s32 newf) dev_disable_change(idev); } } - rcu_read_unlock(); } static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)