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 1D3DAC2BB41 for ; Tue, 16 Aug 2022 08:06:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230453AbiHPIG0 (ORCPT ); Tue, 16 Aug 2022 04:06:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58404 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231671AbiHPIFH (ORCPT ); Tue, 16 Aug 2022 04:05:07 -0400 Received: from smtp-fw-2101.amazon.com (smtp-fw-2101.amazon.com [72.21.196.25]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3DB1C10E978; Mon, 15 Aug 2022 22:27:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1660627639; x=1692163639; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=EnreeUAy6WY30UmIjYDHl/Mw/87V/rQunE2Mfxra1MY=; b=T4IQxMm5kYQdWspkbyCllCavyd0E+zvQbKlBqYlbigRYEbiA2bvcfGza w1i/0T/44M3KDIpF21R/JNd2JoHg2tv6U9f69XgAy29ycKITXObruuo6d iQz0iRmu1aELb3Hjm8P+/LoduQ1PuLphF0B3MhjVFrlzHFeprdnMOgyzB 4=; X-IronPort-AV: E=Sophos;i="5.93,240,1654560000"; d="scan'208";a="230040066" Received: from iad12-co-svc-p1-lb1-vlan3.amazon.com (HELO email-inbound-relay-iad-1a-b09d0114.us-east-1.amazon.com) ([10.43.8.6]) by smtp-border-fw-2101.iad2.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Aug 2022 05:27:18 +0000 Received: from EX13MTAUWB001.ant.amazon.com (iad12-ws-svc-p26-lb9-vlan3.iad.amazon.com [10.40.163.38]) by email-inbound-relay-iad-1a-b09d0114.us-east-1.amazon.com (Postfix) with ESMTPS id 757DC81151; Tue, 16 Aug 2022 05:27:15 +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; Tue, 16 Aug 2022 05:27:14 +0000 Received: from 88665a182662.ant.amazon.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; Tue, 16 Aug 2022 05:27:11 +0000 From: Kuniyuki Iwashima To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni CC: Kuniyuki Iwashima , Kuniyuki Iwashima , , , Eliezer Tamir Subject: [PATCH v1 net 12/15] net: Fix a data-race around sysctl_net_busy_poll. Date: Mon, 15 Aug 2022 22:23:44 -0700 Message-ID: <20220816052347.70042-13-kuniyu@amazon.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220816052347.70042-1-kuniyu@amazon.com> References: <20220816052347.70042-1-kuniyu@amazon.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Originating-IP: [10.43.160.55] X-ClientProxiedBy: EX13D24UWB003.ant.amazon.com (10.43.161.222) To EX19D004ANA001.ant.amazon.com (10.37.240.138) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org While reading sysctl_net_busy_poll, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 060212928670 ("net: add low latency socket poll") Signed-off-by: Kuniyuki Iwashima --- CC: Eliezer Tamir --- include/net/busy_poll.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/net/busy_poll.h b/include/net/busy_poll.h index c4898fcbf923..f90f0021f5f2 100644 --- a/include/net/busy_poll.h +++ b/include/net/busy_poll.h @@ -33,7 +33,7 @@ extern unsigned int sysctl_net_busy_poll __read_mostly; static inline bool net_busy_loop_on(void) { - return sysctl_net_busy_poll; + return READ_ONCE(sysctl_net_busy_poll); } static inline bool sk_can_busy_loop(const struct sock *sk) -- 2.30.2