[{"id":1768243,"web_url":"http://patchwork.ozlabs.org/comment/1768243/","msgid":"<16f16af0-383b-9089-93c7-75494ec5031e@gmail.com>","list_archive_url":null,"date":"2017-09-13T23:28:40","subject":"Re: [PATCH v2] net: smsc911x: Quieten netif during suspend","submitter":{"id":2800,"url":"http://patchwork.ozlabs.org/api/people/2800/","name":"Florian Fainelli","email":"f.fainelli@gmail.com"},"content":"On 09/13/2017 10:42 AM, Geert Uytterhoeven wrote:\n> If the network interface is kept running during suspend, the net core\n> may call net_device_ops.ndo_start_xmit() while the Ethernet device is\n> still suspended, which may lead to a system crash.\n> \n> E.g. on sh73a0/kzm9g and r8a73a4/ape6evm, the external Ethernet chip is\n> driven by a PM controlled clock. If the Ethernet registers are accessed\n> while the clock is not running, the system will crash with an imprecise\n> external abort.\n> \n> As this is a race condition with a small time window, it is not so easy\n> to trigger at will. Using pm_test may increase your chances:\n> \n> # echo 0 > /sys/module/printk/parameters/console_suspend\n> # echo platform > /sys/power/pm_test\n> # echo mem > /sys/power/state\n> \n> To fix this, make sure the network interface is quietened during\n> suspend.\n> \n> Signed-off-by: Geert Uytterhoeven \n\nReviewed-by: Florian Fainelli \n\nYou may want to take the opportunity to suspend the PHY device\n(conversely resume it) if WoL is not enabled on this device.\n\nThanks!\n\n> ---\n> This is v2 of the series \"[PATCH 0/2] net: Fix crashes due to activity\n> during suspend\", which degenerated into a single patch after commit\n> ebc8254aeae34226 (\"Revert \"net: phy: Correctly process PHY_HALTED in\n> phy_stop_machine()\"\") made \"[PATCH 1/2] net: phy: Freeze PHY polling before\n> suspending devices\" no longer needed.\n> \n> v2:\n> - Spelling s/quit/quiet/g.\n> \n> No stacktrace is provided, as the imprecise external abort is usually\n> reported from an innocent looking and unrelated function like\n> __loop_delay(), cpu_idle_poll(), or arch_timer_read_counter_long().\n> ---\n> drivers/net/ethernet/smsc/smsc911x.c | 15 ++++++++++++++-\n> 1 file changed, 14 insertions(+), 1 deletion(-)\n> \n> diff --git a/drivers/net/ethernet/smsc/smsc911x.c b/drivers/net/ethernet/smsc/smsc911x.c\n> index 0b6a39b003a4e188..012fb66eed8dd618 100644\n> --- a/drivers/net/ethernet/smsc/smsc911x.c\n> +++ b/drivers/net/ethernet/smsc/smsc911x.c\n> @@ -2595,6 +2595,11 @@ static int smsc911x_suspend(struct device *dev)\n> \tstruct net_device *ndev = dev_get_drvdata(dev);\n> \tstruct smsc911x_data *pdata = netdev_priv(ndev);\n> \n> +\tif (netif_running(ndev)) {\n> +\t\tnetif_stop_queue(ndev);\n> +\t\tnetif_device_detach(ndev);\n> +\t}\n> +\n> \t/* enable wake on LAN, energy detection and the external PME\n> \t * signal. */\n> \tsmsc911x_reg_write(pdata, PMT_CTRL,\n> @@ -2628,7 +2633,15 @@ static int smsc911x_resume(struct device *dev)\n> \twhile (!(smsc911x_reg_read(pdata, PMT_CTRL) & PMT_CTRL_READY_) && --to)\n> \t\tudelay(1000);\n> \n> -\treturn (to == 0) ? -EIO : 0;\n> +\tif (to == 0)\n> +\t\treturn -EIO;\n> +\n> +\tif (netif_running(ndev)) {\n> +\t\tnetif_device_attach(ndev);\n> +\t\tnetif_start_queue(ndev);\n> +\t}\n> +\n> +\treturn 0;\n> }\n> \n> static const struct dev_pm_ops smsc911x_pm_ops = {\n>","headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=netdev-owner@vger.kernel.org;\n\treceiver=)","ozlabs.org; dkim=pass (2048-bit key;\n\tunprotected) header.d=gmail.com header.i=@gmail.com\n\theader.b=\"QKIBeJYc\"; dkim-atps=neutral"],"Received":["from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xsyXv2r7gz9t32\n\tfor ;\n\tThu, 14 Sep 2017 09:29:03 +1000 (AEST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1751421AbdIMX2s (ORCPT );\n\tWed, 13 Sep 2017 19:28:48 -0400","from mail-pg0-f66.google.com ([74.125.83.66]:32998 \"EHLO\n\tmail-pg0-f66.google.com\" rhost-flags-OK-OK-OK-OK) by vger.kernel.org\n\twith ESMTP id S1751125AbdIMX2p (ORCPT\n\t); Wed, 13 Sep 2017 19:28:45 -0400","by mail-pg0-f66.google.com with SMTP id i130so777406pgc.0;\n\tWed, 13 Sep 2017 16:28:45 -0700 (PDT)","from [172.20.169.246] ([12.145.98.253])\n\tby smtp.gmail.com with ESMTPSA id\n\tz83sm25751285pfd.10.2017.09.13.16.28.42\n\t(version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128);\n\tWed, 13 Sep 2017 16:28:43 -0700 (PDT)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=gmail.com; s=20161025;\n\th=subject:to:cc:references:from:message-id:date:user-agent\n\t:mime-version:in-reply-to:content-language:content-transfer-encoding; \n\tbh=RiAeX/GK6h/T83pUSbl+fjZTaEdfr93Y/zzO8XunpFo=;\n\tb=QKIBeJYcxHS5L58tvsolqfPCrpZkFWdOUICMdXqv/O1cQQwNw3QYflBhDWERvSxZf/\n\tuy5JgOvI+zJtZgwKLNoDZuIiUIJaz/8lAdZiVHWiFEQHAD1KYEXVgXXy3/hVL3f/I1A3\n\t2NpHE8Rrp06Ntlbk7ECekbuvcFEDPf+NV2cXpcGBsGRIiMzXH65+hqADyFr3ZSl5Urfm\n\tfEUe12rXBOLxlIcjNB4PnELrLnYtTRICNrKfaWiMXa9Ykm5EkAAWEZly3lgVgMo46umi\n\td7m7fa6FD+7jAj87440j3nI/xRBUDQoaGXUhX6VaIGNiiaEPCR3laCFpkpGfG646GFku\n\t+CRA==","X-Google-DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=1e100.net; s=20161025;\n\th=x-gm-message-state:subject:to:cc:references:from:message-id:date\n\t:user-agent:mime-version:in-reply-to:content-language\n\t:content-transfer-encoding;\n\tbh=RiAeX/GK6h/T83pUSbl+fjZTaEdfr93Y/zzO8XunpFo=;\n\tb=AvI1dt8vfOLbXhPIUB9XQla07iSKEivyY52agCdclWo+h+evgITPntRrK7/hZdikPh\n\ty3X/AY9AvEUMs04K6Es+XjwRtFRN5YXkRigdIBFinCi55H+UXBh5KCk3L4XK/OcnYBRW\n\trT17rlCobG5gJvm4ZRCaaSLcXpUvFIeF2c0weo2H8el6FfPh78OVEuWtcWIx9QYl9xRc\n\tQzcsimGNStBCI7WOBIeSC3QG7E3b5w7oGWy7SsGqTMuiKv8ILwQUzLDpwbhF22AYrsZP\n\tNAHeeF3/ONibhpNIFSK2ICq4edi9Hw17AuuDp209XitB0yi+9RunL8b8d/+8LG1SVcYi\n\teD7g==","X-Gm-Message-State":"AHPjjUiWl4tK7QzRmybL+UYJ7X/gKJuvZyg/kVf/9kZ10s1PXMGnDJMq\n\txeHj0KC9MvjW6X/sa6A=","X-Google-Smtp-Source":"ADKCNb502gI9wuiHQGOPKwd8KssrOzXWeT6wIyEXIQJ4PxAPaU6v4PsrmkSwYO1wgnW1kiyB0BgEiQ==","X-Received":"by 10.98.166.10 with SMTP id t10mr15005506pfe.181.1505345324533; \n\tWed, 13 Sep 2017 16:28:44 -0700 (PDT)","Subject":"Re: [PATCH v2] net: smsc911x: Quieten netif during suspend","To":"Geert Uytterhoeven ,\n\t\"David S . Miller\" ,\n\tSteve Glendinning ","Cc":"Andrew Lunn , netdev@vger.kernel.org,\n\tlinux-pm@vger.kernel.org, linux-renesas-soc@vger.kernel.org,\n\tlinux-kernel@vger.kernel.org","References":"<1505324525-9998-1-git-send-email-geert+renesas@glider.be>","From":"Florian Fainelli ","Message-ID":"<16f16af0-383b-9089-93c7-75494ec5031e@gmail.com>","Date":"Wed, 13 Sep 2017 16:28:40 -0700","User-Agent":"Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101\n\tThunderbird/52.2.1","MIME-Version":"1.0","In-Reply-To":"<1505324525-9998-1-git-send-email-geert+renesas@glider.be>","Content-Type":"text/plain; charset=windows-1252","Content-Language":"en-US","Content-Transfer-Encoding":"7bit","Sender":"netdev-owner@vger.kernel.org","Precedence":"bulk","List-ID":"","X-Mailing-List":"netdev@vger.kernel.org"}},{"id":1768436,"web_url":"http://patchwork.ozlabs.org/comment/1768436/","msgid":"","list_archive_url":null,"date":"2017-09-14T09:09:54","subject":"Re: [PATCH v2] net: smsc911x: Quieten netif during suspend","submitter":{"id":703,"url":"http://patchwork.ozlabs.org/api/people/703/","name":"Geert Uytterhoeven","email":"geert@linux-m68k.org"},"content":"Hi Florian,\n\nOn Thu, Sep 14, 2017 at 1:28 AM, Florian Fainelli wrote:\n> On 09/13/2017 10:42 AM, Geert Uytterhoeven wrote:\n>> If the network interface is kept running during suspend, the net core\n>> may call net_device_ops.ndo_start_xmit() while the Ethernet device is\n>> still suspended, which may lead to a system crash.\n>>\n>> E.g. on sh73a0/kzm9g and r8a73a4/ape6evm, the external Ethernet chip is\n>> driven by a PM controlled clock. If the Ethernet registers are accessed\n>> while the clock is not running, the system will crash with an imprecise\n>> external abort.\n>>\n>> As this is a race condition with a small time window, it is not so easy\n>> to trigger at will. Using pm_test may increase your chances:\n>>\n>> # echo 0 > /sys/module/printk/parameters/console_suspend\n>> # echo platform > /sys/power/pm_test\n>> # echo mem > /sys/power/state\n>>\n>> To fix this, make sure the network interface is quietened during\n>> suspend.\n>>\n>> Signed-off-by: Geert Uytterhoeven \n\n> Reviewed-by: Florian Fainelli \n\nThank you!\n\n> You may want to take the opportunity to suspend the PHY device\n> (conversely resume it) if WoL is not enabled on this device.\n\nDespite the WoL comment visible in the context below, I believe this driver\ndoesn't support WoL yet (ethtool_ops.[gs]et_wol() not implemented).\n\n>> --- a/drivers/net/ethernet/smsc/smsc911x.c\n>> +++ b/drivers/net/ethernet/smsc/smsc911x.c\n>> @@ -2595,6 +2595,11 @@ static int smsc911x_suspend(struct device *dev)\n>> struct net_device *ndev = dev_get_drvdata(dev);\n>> struct smsc911x_data *pdata = netdev_priv(ndev);\n>>\n>> + if (netif_running(ndev)) {\n>> + netif_stop_queue(ndev);\n>> + netif_device_detach(ndev);\n>> + }\n>> +\n>> /* enable wake on LAN, energy detection and the external PME\n>> * signal. */\n>> smsc911x_reg_write(pdata, PMT_CTRL,\n\nGr{oetje,eeting}s,\n\n Geert\n\n--\nGeert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org\n\nIn personal conversations with technical people, I call myself a hacker. But\nwhen I'm talking to journalists I just say \"programmer\" or something like that.\n -- Linus Torvalds","headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=netdev-owner@vger.kernel.org;\n\treceiver=)","ozlabs.org;\n\tdkim=fail reason=\"signature verification failed\" (2048-bit key;\n\tunprotected) header.d=gmail.com header.i=@gmail.com\n\theader.b=\"cUav/+sa\"; dkim-atps=neutral"],"Received":["from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xtCRR3sCJz9sBZ\n\tfor ;\n\tThu, 14 Sep 2017 19:10:11 +1000 (AEST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1751519AbdINJJ5 (ORCPT );\n\tThu, 14 Sep 2017 05:09:57 -0400","from mail-pf0-f196.google.com ([209.85.192.196]:36193 \"EHLO\n\tmail-pf0-f196.google.com\" rhost-flags-OK-OK-OK-OK) by vger.kernel.org\n\twith ESMTP id S1751385AbdINJJz (ORCPT\n\t); Thu, 14 Sep 2017 05:09:55 -0400","by mail-pf0-f196.google.com with SMTP id f84so1245579pfj.3;\n\tThu, 14 Sep 2017 02:09:55 -0700 (PDT)","by 10.100.160.13 with HTTP; Thu, 14 Sep 2017 02:09:54 -0700 (PDT)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=gmail.com; s=20161025;\n\th=mime-version:sender:in-reply-to:references:from:date:message-id\n\t:subject:to:cc;\n\tbh=AJpdC1fTsMexCEFmmMxs37uCjB6PRGkxf6e1zXz9SMg=;\n\tb=cUav/+saVUKiWPMmMWN60UkMGCUdYItfJPBYrxy77r8Nk0C3ofB3xp+Gj4YcwEfK0f\n\tHB6ZtDaYqf0kq8iPyockF9zoGxQl+xsnYlBd/EDnLzN5kAZMxVgMpy6zrTbZbHTwkohI\n\trzCtTYNDBdyP4JMmkJjy4DkOh19csol2aavYWRC0kk5pvalTJWooBl0aFLsKzhR0oDes\n\tgPEViLbHvsWsEKlzndYm75yXu5u6ukx5ibAm/jOHYtLinVM/6Xh7BqkwdIT4KUWUHxZe\n\tQcBAu2gxtNSr+WsnXXO7j7J/MTivqIbEdQdLRvF/ON2hKa3k0p3f++YwwNGA/S0teFOG\n\tLUDA==","X-Google-DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=1e100.net; s=20161025;\n\th=x-gm-message-state:mime-version:sender:in-reply-to:references:from\n\t:date:message-id:subject:to:cc;\n\tbh=AJpdC1fTsMexCEFmmMxs37uCjB6PRGkxf6e1zXz9SMg=;\n\tb=Qv5XiNdLv9RtHatN6tEWzx6S5GNnq6vhgzVdBzVF5lMKKQjJBFg1KLS/4Zg3GHthTj\n\tYEUXQFcDCAy8AtgHTcmPB/V7drFFn1qT2zZBAMErE56DW0QBttjOwGXgbmRL4fpPOXf2\n\tNsK1K6JdrGIeIiNs0bE0VwIPzeARWsZlAuYzbIYMaVNbWUAWH91OoZ/mGo4DfPBqNd16\n\tPSXfcspPN4u8V5MjSzur5fmuUcKrE9w6r/wJi/oIjyixGZBpxemftdgHTup/T1YAOpmj\n\tdvgianAeuNXAGu86blldYyHPzAgcsYwrjz1TylTBjFdcJx4Ih/vlrHmc0C9IY+G8fqEI\n\tSybQ==","X-Gm-Message-State":"AHPjjUgDbL+TiiQ/0H/G1o+Yb6p/Kx1R6iUnu0QX6OR9Kg2iyRIaM+5H\n\tP+Wb2sDhdX3FM5CyHlMpHwnHUyxGDMqE4GimuXM=","X-Google-Smtp-Source":"ADKCNb7CREIkKzhW9ISS2rYlB2oUk5md383dogMiE4MCN1bLrOUfUtQA0eGk44ZmItvy3IVzisFr27rHE8EiialOog8=","X-Received":"by 10.99.103.2 with SMTP id b2mr12355764pgc.177.1505380194812;\n\tThu, 14 Sep 2017 02:09:54 -0700 (PDT)","MIME-Version":"1.0","In-Reply-To":"<16f16af0-383b-9089-93c7-75494ec5031e@gmail.com>","References":"<1505324525-9998-1-git-send-email-geert+renesas@glider.be>\n\t<16f16af0-383b-9089-93c7-75494ec5031e@gmail.com>","From":"Geert Uytterhoeven ","Date":"Thu, 14 Sep 2017 11:09:54 +0200","X-Google-Sender-Auth":"uBDDQzHRHj2PKNVsN0BVHQAwuf4","Message-ID":"","Subject":"Re: [PATCH v2] net: smsc911x: Quieten netif during suspend","To":"Florian Fainelli ","Cc":"Geert Uytterhoeven ,\n\t\"David S . Miller\" ,\n\tSteve Glendinning ,\n\tAndrew Lunn ,\n\t\"netdev@vger.kernel.org\" ,\n\tLinux PM list ,\n\tLinux-Renesas ,\n\t\"linux-kernel@vger.kernel.org\" ","Content-Type":"text/plain; charset=\"UTF-8\"","Sender":"netdev-owner@vger.kernel.org","Precedence":"bulk","List-ID":"","X-Mailing-List":"netdev@vger.kernel.org"}},{"id":1769462,"web_url":"http://patchwork.ozlabs.org/comment/1769462/","msgid":"<20170915.142622.1357636170906048191.davem@davemloft.net>","list_archive_url":null,"date":"2017-09-15T21:26:22","subject":"Re: [PATCH v2] net: smsc911x: Quieten netif during suspend","submitter":{"id":15,"url":"http://patchwork.ozlabs.org/api/people/15/","name":"David Miller","email":"davem@davemloft.net"},"content":"From: Geert Uytterhoeven \nDate: Wed, 13 Sep 2017 19:42:05 +0200\n\n> If the network interface is kept running during suspend, the net core\n> may call net_device_ops.ndo_start_xmit() while the Ethernet device is\n> still suspended, which may lead to a system crash.\n> \n> E.g. on sh73a0/kzm9g and r8a73a4/ape6evm, the external Ethernet chip is\n> driven by a PM controlled clock. If the Ethernet registers are accessed\n> while the clock is not running, the system will crash with an imprecise\n> external abort.\n> \n> As this is a race condition with a small time window, it is not so easy\n> to trigger at will. Using pm_test may increase your chances:\n> \n> # echo 0 > /sys/module/printk/parameters/console_suspend\n> # echo platform > /sys/power/pm_test\n> # echo mem > /sys/power/state\n> \n> To fix this, make sure the network interface is quietened during\n> suspend.\n> \n> Signed-off-by: Geert Uytterhoeven \n\nApplied.","headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Authentication-Results":"ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=netdev-owner@vger.kernel.org;\n\treceiver=)","Received":["from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xv7kh6HX6z9s7B\n\tfor ;\n\tSat, 16 Sep 2017 07:26:36 +1000 (AEST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1751871AbdIOV0Z (ORCPT );\n\tFri, 15 Sep 2017 17:26:25 -0400","from shards.monkeyblade.net ([184.105.139.130]:57290 \"EHLO\n\tshards.monkeyblade.net\" rhost-flags-OK-OK-OK-OK) by vger.kernel.org\n\twith ESMTP id S1751705AbdIOV0X (ORCPT\n\t); Fri, 15 Sep 2017 17:26:23 -0400","from localhost (74-93-104-98-Washington.hfc.comcastbusiness.net\n\t[74.93.104.98]) (using TLSv1 with cipher AES256-SHA (256/256 bits))\n\t(Client did not present a certificate)\n\t(Authenticated sender: davem-davemloft)\n\tby shards.monkeyblade.net (Postfix) with ESMTPSA id 3968A133F6547;\n\tFri, 15 Sep 2017 14:26:23 -0700 (PDT)"],"Date":"Fri, 15 Sep 2017 14:26:22 -0700 (PDT)","Message-Id":"<20170915.142622.1357636170906048191.davem@davemloft.net>","To":"geert+renesas@glider.be","Cc":"steve.glendinning@shawell.net, andrew@lunn.ch,\n\tf.fainelli@gmail.com, netdev@vger.kernel.org,\n\tlinux-pm@vger.kernel.org, linux-renesas-soc@vger.kernel.org,\n\tlinux-kernel@vger.kernel.org","Subject":"Re: [PATCH v2] net: smsc911x: Quieten netif during suspend","From":"David Miller ","In-Reply-To":"<1505324525-9998-1-git-send-email-geert+renesas@glider.be>","References":"<1505324525-9998-1-git-send-email-geert+renesas@glider.be>","X-Mailer":"Mew version 6.7 on Emacs 25.2 / Mule 6.0 (HANACHIRUSATO)","Mime-Version":"1.0","Content-Type":"Text/Plain; charset=us-ascii","Content-Transfer-Encoding":"7bit","X-Greylist":"Sender succeeded SMTP AUTH, not delayed by\n\tmilter-greylist-4.5.12 (shards.monkeyblade.net\n\t[149.20.54.216]); Fri, 15 Sep 2017 14:26:23 -0700 (PDT)","Sender":"netdev-owner@vger.kernel.org","Precedence":"bulk","List-ID":"","X-Mailing-List":"netdev@vger.kernel.org"}}]