From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2C7EDC00140 for ; Thu, 18 Aug 2022 03:57:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242850AbiHRD5H (ORCPT ); Wed, 17 Aug 2022 23:57:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50028 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240889AbiHRD5G (ORCPT ); Wed, 17 Aug 2022 23:57:06 -0400 Received: from smtp-fw-6001.amazon.com (smtp-fw-6001.amazon.com [52.95.48.154]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 74DF4A1D7A for ; Wed, 17 Aug 2022 20:57:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1660795026; x=1692331026; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=dk1qqFKGBHe2PX6XY+X2BcgbaI6uUEpULdKbXwkATqs=; b=EZsPUGjrM2AeiJ3F0cMiQINsolxX8c1CvdL+XqtS/g9MpbWDjD4Xrn1d G6sKYLBi2Q1a1yV6HWQUAyXeuGZ/jaPtFG1Q6CPmH54hSkAb43DYvUbJ/ 0vEMsS57oXPemtPZht7Jcps1XFO0cqfqL/Z+u2XNXTPplcA7VVhKDjf09 4=; Received: from iad12-co-svc-p1-lb1-vlan2.amazon.com (HELO email-inbound-relay-iad-1e-26daedd8.us-east-1.amazon.com) ([10.43.8.2]) by smtp-border-fw-6001.iad6.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Aug 2022 03:57:05 +0000 Received: from EX13MTAUWB001.ant.amazon.com (iad12-ws-svc-p26-lb9-vlan2.iad.amazon.com [10.40.163.34]) by email-inbound-relay-iad-1e-26daedd8.us-east-1.amazon.com (Postfix) with ESMTPS id 492E8E0FFC; Thu, 18 Aug 2022 03:57:03 +0000 (UTC) Received: from EX19D004ANA001.ant.amazon.com (10.37.240.138) by EX13MTAUWB001.ant.amazon.com (10.43.161.207) with Microsoft SMTP Server (TLS) id 15.0.1497.38; Thu, 18 Aug 2022 03:57:02 +0000 Received: from 88665a182662.ant.amazon.com.com (10.43.160.55) by EX19D004ANA001.ant.amazon.com (10.37.240.138) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1118.12; Thu, 18 Aug 2022 03:57:00 +0000 From: Kuniyuki Iwashima To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni CC: Kuniyuki Iwashima , Kuniyuki Iwashima , , Dmitry Vyukov Subject: [PATCH v2 net 16/17] net: Fix a data-race around netdev_unregister_timeout_secs. Date: Wed, 17 Aug 2022 20:52:26 -0700 Message-ID: <20220818035227.81567-17-kuniyu@amazon.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220818035227.81567-1-kuniyu@amazon.com> References: <20220818035227.81567-1-kuniyu@amazon.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Originating-IP: [10.43.160.55] X-ClientProxiedBy: EX13D29UWA002.ant.amazon.com (10.43.160.63) To EX19D004ANA001.ant.amazon.com (10.37.240.138) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org While reading netdev_unregister_timeout_secs, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 5aa3afe107d9 ("net: make unregister netdev warning timeout configurable") Signed-off-by: Kuniyuki Iwashima --- CC: Dmitry Vyukov --- net/core/dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/core/dev.c b/net/core/dev.c index 8221322d86db..56c8b0921c9f 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -10284,7 +10284,7 @@ static struct net_device *netdev_wait_allrefs_any(struct list_head *list) return dev; if (time_after(jiffies, warning_time + - netdev_unregister_timeout_secs * HZ)) { + READ_ONCE(netdev_unregister_timeout_secs) * HZ)) { list_for_each_entry(dev, list, todo_list) { pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n", dev->name, netdev_refcnt_read(dev)); -- 2.30.2