From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 85C683376BA; Tue, 26 Aug 2025 13:32:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.189 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756215171; cv=none; b=DY2EJgtWGt4paAdGTwK8huCtDky+ohewix3KB9OQzIssAoTBATO79XSr1vQCLYXrDsEGWy+2/TlmIHenGkTm0IefmIsOqMPpgPKVlwsW05olCJ9YoZ2GWjoqfym2Hs25/eIgN/tldYsLjH0G039lfAPgJlc4hFAzHS3n2jvGnJ0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756215171; c=relaxed/simple; bh=2P/jEUIrcly5M6ffvXr+n6/JwLUJRxYguv1L+Q/9jP0=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=qOFiQUn78tQc3rpOhAe9KSDMS2T2UTaI/V2DUwg5usgZOsGwIS86WXsQAijCp1bfjRWmvSOnQ8j4fsi35a5lkF4JvTWd8tEi/xwfHIOLQ7NWVCVl1Xn/HI7Al1/q+jIkLEvxLdN/WytqjVlB7x2NQXTArl3ihLh8WvItIUeXULk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.189 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.162.254]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4cB7lQ0x1JzdcGS; Tue, 26 Aug 2025 21:28:18 +0800 (CST) Received: from dggpemf500002.china.huawei.com (unknown [7.185.36.57]) by mail.maildlp.com (Postfix) with ESMTPS id DAC1C18048F; Tue, 26 Aug 2025 21:32:43 +0800 (CST) Received: from [10.174.179.113] (10.174.179.113) by dggpemf500002.china.huawei.com (7.185.36.57) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Tue, 26 Aug 2025 21:32:42 +0800 Message-ID: Date: Tue, 26 Aug 2025 21:32:34 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net-next] ipv6: annotate data-races around devconf->rpl_seg_enabled To: Kuniyuki Iwashima CC: , , , , , , , References: <20250826025206.303325-1-yuehaibing@huawei.com> Content-Language: en-US From: Yue Haibing In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-ClientProxiedBy: kwepems200002.china.huawei.com (7.221.188.68) To dggpemf500002.china.huawei.com (7.185.36.57) On 2025/8/26 11:17, Kuniyuki Iwashima wrote: > On Mon, Aug 25, 2025 at 7:51 PM Yue Haibing wrote: >> >> devconf->rpl_seg_enabled can be changed concurrently from >> /proc/sys/net/ipv6/conf, annotate lockless reads on it. >> >> Signed-off-by: Yue Haibing >> --- >> net/ipv6/exthdrs.c | 6 ++---- >> 1 file changed, 2 insertions(+), 4 deletions(-) >> >> diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c >> index d1ef9644f826..a23eb8734e15 100644 >> --- a/net/ipv6/exthdrs.c >> +++ b/net/ipv6/exthdrs.c >> @@ -494,10 +494,8 @@ static int ipv6_rpl_srh_rcv(struct sk_buff *skb) >> >> idev = __in6_dev_get(skb->dev); >> >> - accept_rpl_seg = net->ipv6.devconf_all->rpl_seg_enabled; >> - if (accept_rpl_seg > idev->cnf.rpl_seg_enabled) >> - accept_rpl_seg = idev->cnf.rpl_seg_enabled; >> - >> + accept_rpl_seg = min(READ_ONCE(net->ipv6.devconf_all->rpl_seg_enabled), >> + READ_ONCE(idev->cnf.rpl_seg_enabled)); >> if (!accept_rpl_seg) { > > Orthogonal to this change, but rpl_seg_enabled is missing .extra1/2 > or this condition should be adjusted like other knobs that recognises > <0 as disabled, .e.g. keep_addr_on_down, etc. Thanks, will add .extra1/2 check for this in v2. > > >> kfree_skb(skb); >> return -1; >> -- >> 2.34.1 >> >