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=-19.0 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, 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 1F290C4360C for ; Mon, 15 Mar 2021 14:49:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D9DC764E1F for ; Mon, 15 Mar 2021 14:49:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239842AbhCOOrT (ORCPT ); Mon, 15 Mar 2021 10:47:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:36622 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232538AbhCON7B (ORCPT ); Mon, 15 Mar 2021 09:59:01 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3666264F16; Mon, 15 Mar 2021 13:58:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1615816726; bh=voN5GC2jBVqqyGZqVEMLRnsVMzQyPZ27Qf1ySvlWgEg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FThO0avml35lrGCaxgWNGsKHcLx5cM79GBatffaDyCpq17VCeRj4RRTfl5fJNziZC Y3bmlZD/XQo7H9vR/T6Hiu/6wrF5EDs1eV2lIgHolE73IZaOmCx45y/3iwvuUeAwm6 Et1AXqIGgPniykuzJGIuqbHGoCpC+JgFgMmBaCZg= From: gregkh@linuxfoundation.org To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Joakim Zhang , Jakub Kicinski Subject: [PATCH 4.19 030/120] net: stmmac: fix watchdog timeout during suspend/resume stress test Date: Mon, 15 Mar 2021 14:56:21 +0100 Message-Id: <20210315135720.975291411@linuxfoundation.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210315135720.002213995@linuxfoundation.org> References: <20210315135720.002213995@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: Greg Kroah-Hartman From: Joakim Zhang commit c511819d138de38e1637eedb645c207e09680d0f upstream. stmmac_xmit() call stmmac_tx_timer_arm() at the end to modify tx timer to do the transmission cleanup work. Imagine such a situation, stmmac enters suspend immediately after tx timer modified, it's expire callback stmmac_tx_clean() would not be invoked. This could affect BQL, since netdev_tx_sent_queue() has been called, but netdev_tx_completed_queue() have not been involved, as a result, dql_avail(&dev_queue->dql) finally always return a negative value. __dev_queue_xmit->__dev_xmit_skb->qdisc_run->__qdisc_run->qdisc_restart->dequeue_skb: if ((q->flags & TCQ_F_ONETXQUEUE) && netif_xmit_frozen_or_stopped(txq)) // __QUEUE_STATE_STACK_XOFF is set Net core will stop transmitting any more. Finillay, net watchdong would timeout. To fix this issue, we should call netdev_tx_reset_queue() in stmmac_resume(). Fixes: 54139cf3bb33 ("net: stmmac: adding multiple buffers for rx") Signed-off-by: Joakim Zhang Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -4566,6 +4566,8 @@ static void stmmac_reset_queues_param(st tx_q->cur_tx = 0; tx_q->dirty_tx = 0; tx_q->mss = 0; + + netdev_tx_reset_queue(netdev_get_tx_queue(priv->dev, queue)); } }