From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934957Ab0GOXIi (ORCPT ); Thu, 15 Jul 2010 19:08:38 -0400 Received: from cavan.codon.org.uk ([93.93.128.6]:49624 "EHLO cavan.codon.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933383Ab0GOXIh (ORCPT ); Thu, 15 Jul 2010 19:08:37 -0400 Date: Fri, 16 Jul 2010 00:08:25 +0100 From: Matthew Garrett To: Henrique de Moraes Holschuh Cc: Pedro Ribeiro , eusou15@yahoo.com, linux-kernel@vger.kernel.org, toralf.foerster@gmx.de, ibm-acpi-devel@lists.sourceforge.net Subject: Re: [ibm-acpi-devel] [PATCH] Remove 9 second reboot delay on Lenovo T400/T500 Message-ID: <20100715230825.GA31651@srcf.ucam.org> References: <4C3DCAA4.9050602@gmail.com> <20100714143625.GA30721@srcf.ucam.org> <20100715223149.GC27512@khazad-dum.debian.net> <20100715225022.GA31377@srcf.ucam.org> <20100715230023.GE27512@khazad-dum.debian.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100715230023.GE27512@khazad-dum.debian.net> User-Agent: Mutt/1.5.18 (2008-05-17) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: mjg59@cavan.codon.org.uk X-SA-Exim-Scanned: No (on cavan.codon.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 15, 2010 at 08:00:23PM -0300, Henrique de Moraes Holschuh wrote: > Do you want to escalate this to Lenovo? I need a clear and consise > description of the problem and the boxes we know to be affected. Well, right now we're not doing precisely what Windows does. The other possibility is that when the keyboard controller write triggers some SMM code, it makes an assumption about some piece of hardware state that isn't true and loops for a while to see if it changes. If we knew what that was then we could ensure that we're performing the same state change on our way down to reboot. One thing that would be worth checking is whether performing the keyboard controller writes from userspace with a minimal kernel and init=/bin/bash shows the 9-second pause or not - and then, ideally, see whether the same is also true under DOS. -- Matthew Garrett | mjg59@srcf.ucam.org