From patchwork Tue Nov 4 16:08:05 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Giuseppe CAVALLARO X-Patchwork-Id: 406671 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id F245B1400A0 for ; Wed, 5 Nov 2014 03:20:26 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754004AbaKDQUH (ORCPT ); Tue, 4 Nov 2014 11:20:07 -0500 Received: from mx07-00178001.pphosted.com ([62.209.51.94]:47601 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751999AbaKDQT7 (ORCPT ); Tue, 4 Nov 2014 11:19:59 -0500 Received: from pps.filterd (m0046670.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.14.5/8.14.5) with SMTP id sA4GFnLF014618 for ; Tue, 4 Nov 2014 17:19:58 +0100 Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com with ESMTP id 1qetgejbvv-1 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT) for ; Tue, 04 Nov 2014 17:19:58 +0100 Received: from zeta.dmz-eu.st.com (zeta.dmz-eu.st.com [164.129.230.9]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 103873D for ; Tue, 4 Nov 2014 16:19:29 +0000 (GMT) Received: from Webmail-eu.st.com (Safex1hubcas21.st.com [10.75.90.44]) by zeta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 32DCF2C2F4 for ; Tue, 4 Nov 2014 16:19:54 +0000 (GMT) Received: from localhost (164.130.129.175) by Webmail-ga.st.com (10.75.90.48) with Microsoft SMTP Server (TLS) id 14.3.181.6; Tue, 4 Nov 2014 17:19:54 +0100 From: Giuseppe Cavallaro To: Cc: Fabrice Gasnier Subject: [PATCH (net.git) 1/5] stmmac: fix stmmac_tx_avail should be called with TX locked Date: Tue, 4 Nov 2014 17:08:05 +0100 Message-ID: <1415117289-7733-2-git-send-email-peppe.cavallaro@st.com> X-Mailer: git-send-email 1.7.4.4 In-Reply-To: <1415117289-7733-1-git-send-email-peppe.cavallaro@st.com> References: <1415117289-7733-1-git-send-email-peppe.cavallaro@st.com> MIME-Version: 1.0 X-Originating-IP: [164.130.129.175] X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.12.52, 1.0.28, 0.0.0000 definitions=2014-11-04_07:2014-11-04, 2014-11-04, 1970-01-01 signatures=0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Fabrice Gasnier stmmac_tx_avail() may lie if used unprotected. It's using cur_tx and dirty_tx index. These index may be already in use by tx_clean when entering xmit routine. So, this should be called locked. This can cause transmit queue to be stuck, with following message: NETDEV WATCHDOG: eth0 (stmmaceth): transmit queue 0 timed out Signed-off-by: Fabrice Gasnier Acked-by: Giuseppe Cavallaro --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 6f77a46..bcd8a34 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -1894,7 +1894,10 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev) unsigned int nopaged_len = skb_headlen(skb); unsigned int enh_desc = priv->plat->enh_desc; + spin_lock(&priv->tx_lock); + if (unlikely(stmmac_tx_avail(priv) < nfrags + 1)) { + spin_unlock(&priv->tx_lock); if (!netif_queue_stopped(dev)) { netif_stop_queue(dev); /* This is a hard error, log it. */ @@ -1903,8 +1906,6 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev) return NETDEV_TX_BUSY; } - spin_lock(&priv->tx_lock); - if (priv->tx_path_in_lpi_mode) stmmac_disable_eee_mode(priv);