From patchwork Mon Feb 22 12:36:02 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 386702 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=ham 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 4190EC433DB for ; Mon, 22 Feb 2021 12:44:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0C70164F1F for ; Mon, 22 Feb 2021 12:44:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231345AbhBVMmm (ORCPT ); Mon, 22 Feb 2021 07:42:42 -0500 Received: from mail.kernel.org ([198.145.29.99]:53740 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231318AbhBVMlp (ORCPT ); Mon, 22 Feb 2021 07:41:45 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8E8D764EEC; Mon, 22 Feb 2021 12:39:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1613997553; bh=BVKT+OOE03fon98gOFRRv3x/EIjL2MbNpKfff9E2laE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Hz3bUooqZaBlAYRgPdDy2FVULzxC/qnM/B7NpfhFGqHFnzJfTJSPsNBqWtFMEBu/J utoqKJYKjYaASsFU32nTwqz19UpkmRYhjyqqFwkUzBT1r6v9OLRaIat1VZc8vgEbCx +8TLQxXnfJ/rEtsyCTin7niaGksTFvOFMJn2ASIc= 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 4.14 36/57] net: watchdog: hold device global xmit lock during tx disable Date: Mon, 22 Feb 2021 13:36:02 +0100 Message-Id: <20210222121030.379629059@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210222121027.174911182@linuxfoundation.org> References: <20210222121027.174911182@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@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 @@ -3674,6 +3674,7 @@ 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); @@ -3681,6 +3682,7 @@ 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(); }