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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 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 93684C352A3 for ; Tue, 11 Feb 2020 17:03:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 63FDF20656 for ; Tue, 11 Feb 2020 17:03:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728040AbgBKRDf (ORCPT ); Tue, 11 Feb 2020 12:03:35 -0500 Received: from mx2.suse.de ([195.135.220.15]:42104 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727767AbgBKRDf (ORCPT ); Tue, 11 Feb 2020 12:03:35 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id EC517BA00; Tue, 11 Feb 2020 17:03:32 +0000 (UTC) Date: Tue, 11 Feb 2020 18:03:31 +0100 From: Jean Delvare To: Mika Westerberg Cc: "Rafael J. Wysocki" , Len Brown , linux-acpi@vger.kernel.org, Wim Van Sebroeck , Guenter Roeck , linux-watchdog@vger.kernel.org, Tom Abraham Subject: Re: wdat_wdt: access width inconsistency Message-ID: <20200211180331.11dbe525@endymion> In-Reply-To: <20200211163753.GK2667@lahna.fi.intel.com> References: <20200210111638.64925c8e@endymion> <20200210112326.GP2667@lahna.fi.intel.com> <20200211141147.20bad275@endymion> <20200211135944.GF2667@lahna.fi.intel.com> <20200211172533.08b27181@endymion> <20200211163753.GK2667@lahna.fi.intel.com> Organization: SUSE Linux X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-suse-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-watchdog-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org On Tue, 11 Feb 2020 18:37:53 +0200, Mika Westerberg wrote: > On Tue, Feb 11, 2020 at 05:25:33PM +0100, Jean Delvare wrote: > > On Tue, 11 Feb 2020 15:59:44 +0200, Mika Westerberg wrote: > > > If the default timeout is short then that might happen but I think WDAT > > > spec had some "reasonable" lower limit. > > > > Could you please point me to the WDAT specification? Somehow my web > > search failed to spot it. > > You can find it here: > > http://msdn.microsoft.com/en-us/windows/hardware/gg463320.aspx > > Most of the ACPI related documents not part of the spec itself are > listed in the following page: > > https://uefi.org/acpi Great, thanks for the info. As I read the specification, it is mandatory to have a timeout >= 5 minutes *if* the watchdog is enabled at boot time. Otherwise the 5 minutes is only a recommendation. I wouldn't be surprised if some hardware vendors do not initialize the timeout value and assume the OS will do it for them. Odds are that Windows does that. Thanks again, -- Jean Delvare SUSE L3 Support