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 X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F3991C433E0 for ; Mon, 22 Feb 2021 13:35:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AE76B64E5C for ; Mon, 22 Feb 2021 13:35:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230224AbhBVNfB (ORCPT ); Mon, 22 Feb 2021 08:35:01 -0500 Received: from mail.kernel.org ([198.145.29.99]:53432 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231529AbhBVMnP (ORCPT ); Mon, 22 Feb 2021 07:43:15 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6A02064F31; Mon, 22 Feb 2021 12:40:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1613997623; bh=ecrkO/CAB5XGhSyWvXvwPaOzStHzU+n6wM8mc6ZYGf0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cZ/VelFVnECq/UYx6Cz0Qs881hIJiHwMiAnURffddAjtC425z7finseidfAYe0jJ1 17Oa2L8P6aAswXrzotywpopqFDdqxgFKOd9A28VI3s6FqM30DHfxi8n+vjb2ljB+59 5yXwxefbo9PjuzGEnJDUfLTnj/y9xSIBr3+xuJ3Q= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Edwin Peer , Jakub Kicinski , "David S. Miller" Subject: [PATCH 4.4 19/35] net: watchdog: hold device global xmit lock during tx disable Date: Mon, 22 Feb 2021 13:36:15 +0100 Message-Id: <20210222121020.925592790@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210222121013.581198717@linuxfoundation.org> References: <20210222121013.581198717@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Edwin Peer commit 3aa6bce9af0e25b735c9c1263739a5639a336ae8 upstream. Prevent netif_tx_disable() running concurrently with dev_watchdog() by taking the device global xmit lock. Otherwise, the recommended: netif_carrier_off(dev); netif_tx_disable(dev); driver shutdown sequence can happen after the watchdog has already checked carrier, resulting in possible false alarms. This is because netif_tx_lock() only sets the frozen bit without maintaining the locks on the individual queues. Fixes: c3f26a269c24 ("netdev: Fix lockdep warnings in multiqueue configurations.") Signed-off-by: Edwin Peer Reviewed-by: Jakub Kicinski Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/linux/netdevice.h | 2 ++ 1 file changed, 2 insertions(+) --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3428,6 +3428,7 @@ static inline void netif_tx_disable(stru local_bh_disable(); cpu = smp_processor_id(); + spin_lock(&dev->tx_global_lock); for (i = 0; i < dev->num_tx_queues; i++) { struct netdev_queue *txq = netdev_get_tx_queue(dev, i); @@ -3435,6 +3436,7 @@ static inline void netif_tx_disable(stru netif_tx_stop_queue(txq); __netif_tx_unlock(txq); } + spin_unlock(&dev->tx_global_lock); local_bh_enable(); }