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=-6.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS 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 43966ECDE46 for ; Wed, 24 Oct 2018 19:04:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DE8B0207DD for ; Wed, 24 Oct 2018 19:04:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="OhGhn8SP" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DE8B0207DD Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727206AbeJYDd0 (ORCPT ); Wed, 24 Oct 2018 23:33:26 -0400 Received: from merlin.infradead.org ([205.233.59.134]:40342 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726894AbeJYDdZ (ORCPT ); Wed, 24 Oct 2018 23:33:25 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=Content-Transfer-Encoding:Content-Type: In-Reply-To:MIME-Version:Date:Message-ID:From:References:Cc:To:Subject:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=vf7NmdXW31QAmWHsKby9dxcNF2xe2bxZxZLNk9O2f04=; b=OhGhn8SPqIyFRWkEHQ1MFBCWde wts4gHEqpfpDaIxKcFcZQN6ZDZjs6PrzeWFYEaFj5LsCnW5bhPzcX/vf47+srb7pc4Ao064JPwv8I ZTS4gbTXnW8i3rwZArsGOhjGw/VCmsn0WjwWzcuN9lsb5Hj/Ihv6R+nYzeSqWTDjV7zpC8Atar6ff ajPK4v0eeU+DQzK21UN3I3UmAacJp8+Nbn56APqAWvsDq5o3/eKgF1fkkLMcdL2FhZ1fkXRf2ve2U kM7IXCUUE2PSdu4vnHmCnorzFzKZS8bHJ+5CllAPEcc9ic2Tg+FIFnXBcjTZ/qTADOe6uHq51+2dQ hk/m4cuA==; Received: from static-50-53-52-16.bvtn.or.frontiernet.net ([50.53.52.16] helo=midway.dunlab) by merlin.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1gFORu-0001OP-8u; Wed, 24 Oct 2018 19:04:10 +0000 Subject: Re: [PATCH] V4 init/main.c Enable watchdog_thresh control from kernel line To: Laurence Oberman , linux-kernel@vger.kernel.org Cc: tglx@linutronix.de References: <1540404366-26999-1-git-send-email-loberman@redhat.com> From: Randy Dunlap Message-ID: <36049726-3d4c-f930-2081-3c958ddbc8d9@infradead.org> Date: Wed, 24 Oct 2018 12:04:09 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <1540404366-26999-1-git-send-email-loberman@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/24/18 11:06 AM, Laurence Oberman wrote: > Both graphics and serial consoles are exposed to hard lockups > when handling a large amount of messaging. The kernel watchdog_thresh > parameter up to now has not been available to be set on the kernel line for > early boot. > This patch allows the setting of watchdog_thresh to be increased > when needed to avoid the hard lockups in the console code. > > Signed-off-by: Laurence Oberman > --- > Documentation/admin-guide/kernel-parameters.txt | 7 +++++++ > init/main.c | 8 ++++++++ > 2 files changed, 15 insertions(+) > Laurence, Here are a few more changes for you to consider. > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index 4cdcd1a..05f76b8 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -4932,6 +4932,13 @@ > or other driver-specific files in the > Documentation/watchdog/ directory. > > + watchdog_thresh= > + This parameter allows early boot to change the > + value of the watchdog timeout threshold from the default > + of 10 seconds to avoid hard lockups. Example: > + watchdog_thresh=30 No extra char indent above. > + Default: 10 > + > workqueue.watchdog_thresh= > If CONFIG_WQ_WATCHDOG is configured, workqueue can > warn stall conditions and dump internal state to > diff --git a/init/main.c b/init/main.c > index 1c3f902..ae45291 100644 > --- a/init/main.c > +++ b/init/main.c > @@ -1038,6 +1038,14 @@ static int __init set_debug_rodata(char *str) > __setup("rodata=", set_debug_rodata); > #endif > #ifdef CONFIG_LOCKUP_DETECTOR extern int watchdog_thresh; > +static int __init is_watchdog_thresh_setup(char *str) > +{ > + get_option(&str, &watchdog_thresh); > + return 1; > +} > +__setup("watchdog_thresh=", is_watchdog_thresh_setup); > + #endif and I would change the function name above to just watchdog_thresh_setup() or setup_watchdog_thresh(). > + > #ifdef CONFIG_STRICT_KERNEL_RWX > static void mark_readonly(void) > { > -- ~Randy