From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: [PATCH] ACPI: Add reboot mechanism Date: Tue, 17 Jul 2007 17:41:27 +0200 Message-ID: <200707171741.27628.ak@suse.de> References: <469CD4B8.9070506@shaw.ca> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from mx1.suse.de ([195.135.220.2]:47354 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934618AbXGQPlc (ORCPT ); Tue, 17 Jul 2007 11:41:32 -0400 In-Reply-To: <469CD4B8.9070506@shaw.ca> Content-Disposition: inline Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Robert Hancock Cc: Aaron Durbin , linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, len.brown@intel.com, akpm@osdl.org On Tuesday 17 July 2007 16:39:52 Robert Hancock wrote: > Andi Kleen wrote: > > On Monday 16 July 2007 20:00:19 Aaron Durbin wrote: > >> Add the ability to reset the machine using the RESET_REG in ACPI's FADT table. > > > > Why? I had such a patch at some point as experiment, but it never > > helped actually fix a box. > > Depends if Windows resets using this method,> in that case using it as > well would likely prevent the steady trickle of machines that seem to > have trouble with other reset methods and need blacklist entries.. It's not that easy -- there are different windows versions out who do different things. Sometimes systems are built for older windows versions, sometimes systems are built for newer windows versions. They don't necessarily work on newer versions. But people expect Linux to run on all of them. > I sometimes think that with these sorts of things where basic > functionality like reboot is broken, I'm not aware of that many systems where reboot doesn't work. Also I'm sure there are some who don't reboot even in Windows. Another reason is probably that reboot is quite hard to debug. One recently new problem is that some systems don't have keyboard controllers anymore so that method obviously doesn't work. But it doesn't hurt to try it first because it's unlikely to break something The triple fault fallback is normally quite reliable though. I would expect that putting the ACPI method in the middle is probably safe enough. -Andi