Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762418AbXE1LRb (ORCPT ); Mon, 28 May 2007 07:17:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750729AbXE1LRY (ORCPT ); Mon, 28 May 2007 07:17:24 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:58210 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750724AbXE1LRX (ORCPT ); Mon, 28 May 2007 07:17:23 -0400 From: "Rafael J. Wysocki" To: nigel@nigel.suspend2.net Subject: Re: [RFC][PATCH -mm 3/3] PM: Disable _request_firmware before hibernation/suspend Date: Mon, 28 May 2007 13:22:51 +0200 User-Agent: KMail/1.9.5 Cc: Matthew Garrett , pm list , LKML , Pavel Machek , Alan Stern , Oliver Neukum References: <200705272229.21263.rjw@sisk.pl> <200705272345.04518.rjw@sisk.pl> <1180341026.14749.12.camel@nigel.suspend2.net> In-Reply-To: <1180341026.14749.12.camel@nigel.suspend2.net> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200705281322.52854.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1664 Lines: 39 On Monday, 28 May 2007 10:30, Nigel Cunningham wrote: > Hi. > > On Sun, 2007-05-27 at 23:45 +0200, Rafael J. Wysocki wrote: > > On Sunday, 27 May 2007 22:49, Matthew Garrett wrote: > > > On Sun, May 27, 2007 at 10:31:53PM +0200, Rafael J. Wysocki wrote: > > > > From: Rafael J. Wysocki > > > > > > > > Use a hibernation and suspend notifier to disable the firmware requesting > > > > mechanism before a hibernation/suspend and enable it after the operation. > > > > > > This avoids the problem of .resume methods calling userspace while > > > userspace is frozen and a resulting hang, but does it actually result in > > > the drivers beginning to work again? > > > > Well, this was acutally invented before you've decided to remove the freezing > > of tasks from the suspend code path (which I think is a mistake, but that's > > only my personal opinion, so it doesn't matter very much ;-)) and I regard it > > as a workaround. > > Suspend-to-ram code paths shouldn't assume userspace is unfrozen anyway. > Doesn't [u]swsusp have a code path like Suspend2 where we can suspend to > ram after writing the hibernation image? In that case, it will still be > possible that we seek to enter and leave S3 with processes frozen. That's correct. > Apologies if anyone has already mentioned this - I'm just starting to > play catchup. No one has and that's a valid point, I think. :-) Greetings, Rafael - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/