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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 325D6C35247 for ; Wed, 5 Feb 2020 16:30:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0690121741 for ; Wed, 5 Feb 2020 16:30:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="K6TcvsUY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727081AbgBEQau (ORCPT ); Wed, 5 Feb 2020 11:30:50 -0500 Received: from mail-pf1-f193.google.com ([209.85.210.193]:46976 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726896AbgBEQau (ORCPT ); Wed, 5 Feb 2020 11:30:50 -0500 Received: by mail-pf1-f193.google.com with SMTP id k29so1447434pfp.13; Wed, 05 Feb 2020 08:30:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=oR86uEA/4GyGiJtf79HkkGTWnpzP1H2FQHTGa8XT2B4=; b=K6TcvsUYBNPuNvk68fl5gnw2+qx6fkUwHmLXcFNJezRC0KVyR5+JPUNB9MTZ4WnplH ifQ36vFth1fNNJ9XNNk8e/8EtgJPmMvjsNVRza4aD6+5wEiv46zA29/vVINUnDyWn6Zp x3MMcy2XFPulbdWIVja1FVSywaCalx9XQiy8/9/dal+1scj11DHSk5BB1970KXEMUkj6 o7V/EbHCowKIYeWWPjCzXmM5MIUrOrCrpG1Whv29haWj45FyXw1BTo5Mg7wwWo3wrnck wQhzwjiNL/m1/dr2n5x8bGSesHCWS87jnx6jN6cxUDHm3UJscwotXPeCGe0q/FaywOIR esEA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=oR86uEA/4GyGiJtf79HkkGTWnpzP1H2FQHTGa8XT2B4=; b=GabiROSFM3CNuo+QsJ4DMnf+Az7p7Qdw1PrGd5tmelWNZzb3bL83XFHRtgqOcXTT+P 4wm2Rc5LBnw9ItYGCRzQB5UaVWwDHNkwPO9eumwWlJmYxCV+/aIr76zE87i6TD794L3p hSc4gSVXeKt4HT+cp3+YUyB+LiUOIE8zE330LOtJwVHdmycxNHgdz4/85NIGWK2abx58 16FSD8KFgu94uGczTZedPbYJTnPF1Ve9ZjUK84L+358d3mbg6i4Syo5nGl5ZojEn9ES5 4sCmCxBvQwuF7PbLqg02Y+qMymYhCXwJQLTw/rrEOkiwvBIUvrUHaOxME1SJ+aHULJjI 5giw== X-Gm-Message-State: APjAAAXoozHjipqx7bI/Q/CLRuB4u9pH+gy7K196TEjsddKhHdt/Xi/T 3gt8dlTFyUQYKdOJKSflZcA= X-Google-Smtp-Source: APXvYqyYWNkdo3UpANEYK3QsdDFI13Z9Qw57Dbeh2y5pwKPW5iIhyiNDyYhDsvTPWdcNnfC7OVnsgw== X-Received: by 2002:a63:7c2:: with SMTP id 185mr36415197pgh.446.1580920249982; Wed, 05 Feb 2020 08:30:49 -0800 (PST) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id a18sm28644108pfl.138.2020.02.05.08.30.48 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 05 Feb 2020 08:30:49 -0800 (PST) Date: Wed, 5 Feb 2020 08:30:48 -0800 From: Guenter Roeck To: Mika Westerberg Cc: Jean Delvare , "Rafael J. Wysocki" , Len Brown , linux-acpi@vger.kernel.org, Wim Van Sebroeck , linux-watchdog@vger.kernel.org, Tom Abraham Subject: Re: Forcing non-ACPI watchdog driver Message-ID: <20200205163048.GD25403@roeck-us.net> References: <1580915129.23547.3.camel@suse.de> <20200205152435.GE2667@lahna.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200205152435.GE2667@lahna.fi.intel.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-watchdog-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org On Wed, Feb 05, 2020 at 05:24:35PM +0200, Mika Westerberg wrote: > On Wed, Feb 05, 2020 at 04:05:29PM +0100, Jean Delvare wrote: > > Hi all, > > Hi, > > > Is there a way to prevent the ACPI WDAT watchdog interface from being > > used and force the use of a native watchdog driver instead? > > > > I have a customer who reports a regression on kernel upgrade. Old > > kernel (v4.4) uses iTCO_wdt and watchdog works, new kernel (v4.12) uses > > wdat_wdt and watchdog doesn't work (instant reboot when opening the > > device). While I'm going to look for fixes to backport, I think it > > would be pretty convenient to have a way to just revert to the working > > driver until the new driver is fixed somehow. But I can't see any way > > to do that at the moment, short of disabling ACPI completely, which is > > definitely too extreme to be considered. > > > > Am I missing something? > > You should be able to revert to iTCO_wdt by simply disabling > CONFIG_WDAT_WDT from .config. Then acpi_has_watchdog() returns false > which means that iTCO_wdt is used instead. That may not be possible in a generic distribution. Guenter