Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763626AbYJJTyZ (ORCPT ); Fri, 10 Oct 2008 15:54:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1761648AbYJJTyQ (ORCPT ); Fri, 10 Oct 2008 15:54:16 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:37983 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761147AbYJJTyP (ORCPT ); Fri, 10 Oct 2008 15:54:15 -0400 Date: Fri, 10 Oct 2008 21:53:39 +0200 From: Ingo Molnar To: "Rafael J. Wysocki" Cc: Dave Hansen , "Serge E. Hallyn" , containers@lists.linux-foundation.org, arnd@arndb.de, linux-kernel@vger.kernel.org, Arjan van de Ven , Peter Zijlstra , ACPI Devel Maling List Subject: Re: [RFC][PATCH 2/2] first callers of process_deny_checkpoint() Message-ID: <20081010195339.GA509@elte.hu> References: <20081009190405.13A253CB@kernel> <200810101517.17809.rjw@sisk.pl> <20081010145422.GE11695@elte.hu> <200810102153.45174.rjw@sisk.pl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200810102153.45174.rjw@sisk.pl> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00,DNS_FROM_SECURITYSAGE autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] 0.0 DNS_FROM_SECURITYSAGE RBL: Envelope sender in blackholes.securitysage.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1299 Lines: 32 * Rafael J. Wysocki wrote: > > > Surely not ACPI-compliant. > > > > what do you mean? > > The ACPI spec says quite specifically what should be done while > entering hibernation and during resume from hibernation. We're not > following that in the current code, but we can (gradually) update the > code to become ACPI-compilant in that respect. However, if we go the > checkpointing route, I don't think that will be possible any more. ah, i see. I did not mean to utilize any ACPI paths but simple powerdown or reboot. If we checkpoint all apps to persistent disk areas (which the checkpoint patches in this thread are about), then we can just reboot the kernel and forget all its state. That capability can be used to build a really robust hibernation implementation IMO: we could "hibernate/kexec" over between different kernel versions transparently. (only a small delay will be noticed by the user - if we do it smartly with in-kernel modesetting then not even the screen contents will be changed over this.) Ingo -- 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/