From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932927Ab1CRWAw (ORCPT ); Fri, 18 Mar 2011 18:00:52 -0400 Received: from adelie.canonical.com ([91.189.90.139]:43893 "EHLO adelie.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932859Ab1CRWAl (ORCPT ); Fri, 18 Mar 2011 18:00:41 -0400 Date: Fri, 18 Mar 2011 19:00:35 -0300 From: Herton Ronaldo Krzesinski To: linux-kernel@vger.kernel.org Cc: "Rafael J. Wysocki" Subject: Suspend/resume regression in Toshiba A11 since 2.6.34-rc4 Message-ID: <20110318220034.GA10162@herton-IdeaPad-Y430> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This regression is old, but discovered recently. Since 2.6.34-rc4, a Toshiba Tecra A11 machine resumes without video for the first time. Here is the strange thing reported, on the first suspend/resume, when the machine wakes up the video is blank, but the machine is up (just the screen is black). If you suspend again, on second resume the video comes back normally. Helping the reporter bisecting the problem, we narrowed down the bug to this commit: commit ac7729da880e742613129ee6dea0045328670d2d Author: Rafael J. Wysocki Date: Mon Apr 5 01:43:51 2010 +0200 ACPI / PM: Move ACPI video resume to a PM notifier And reverting this commit on 2.6.38 still made the problem go away. Looking at the commit above I don't saw any problem, and perhaps we have some bad bios here which by moving the resume of acpi video later triggers this bug. Also strange that on second suspend/resume everything is normal... (the regression here is just the video is blank on first resume). I asked the reporter to try to increase brightness logged in remotely when the video is blank after first resume, but this didn't have any effect. This was reported in https://bugs.launchpad.net/bugs/719620 (if reading I recommend to skip to comment #58 and later), I can't think of any solution besides trying to move acpi video resume perhaps back and depend on video device being resume first. I asked for more debugging information but got nothing unfortunately which could diagnose better this... -- []'s Herton