From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: 2.6.25-rc2 System no longer powers off after suspend-to-disk. Screen becomes green. Date: Fri, 22 Feb 2008 18:44:30 +0100 Message-ID: <200802221844.31579.rjw@sisk.pl> References: <200802221802.18640.rjw@sisk.pl> <47BF071C.6040308@rtr.ca> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: Received: from ogre.sisk.pl ([217.79.144.158]:43511 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758499AbYBVRpy (ORCPT ); Fri, 22 Feb 2008 12:45:54 -0500 In-Reply-To: <47BF071C.6040308@rtr.ca> Content-Disposition: inline Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Mark Lord Cc: david@lang.hm, Linus Torvalds , Jesse Barnes , Jeff Chua , lkml , Dave Airlie , linux-acpi@vger.kernel.org, Greg KH On Friday, 22 of February 2008, Mark Lord wrote: > Rafael J. Wysocki wrote: > > On Friday, 22 of February 2008, Mark Lord wrote: > >> david@lang.hm wrote: > >> .. > >>> I've been watching for kexec hibernate for a little while now, and the > >>> last I saw was that acpi was incompatible with the kexec hibernate (but > >>> the suspend folks were still claiming that devices needed to be put in > >>> the 'right mode' not just powered off. I've been waiting to see this > >>> resolved. > >> .. > >> > >> Yeah, exactly. What's so special about poweroff on hibernation? > >> Why even bother with the special "S4" state there? > > > > (1) To be able to wake up with the help of devices that can't wake > > the system up from S5 (power off) > > (2) To handle some platform devices appropriately over the cycle > .. > > That's the theory. I've read about it, but have yet to imagine > any real-life situation where it applies. > > But this isn't my speciality, so.. do you have experience with any real examples? Yup. The fan in my notebook behaves incorrectly after a resume from hibernation if S5 is entered instead of S4 during it. I don't know why exactly it happens, but that's how it goes. Also, some machines are reported to behave incorrectly after a "shutdown" mode hibernation, while the same machines work just fine after a "platform" mode hibernation. So at least for these machines it seems to matter. Thanks, Rafael