From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754414AbZBCXT0 (ORCPT ); Tue, 3 Feb 2009 18:19:26 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751698AbZBCXTR (ORCPT ); Tue, 3 Feb 2009 18:19:17 -0500 Received: from smtp1.linux-foundation.org ([140.211.169.13]:53732 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751374AbZBCXTQ (ORCPT ); Tue, 3 Feb 2009 18:19:16 -0500 Date: Tue, 3 Feb 2009 15:18:14 -0800 (PST) From: Linus Torvalds X-X-Sender: torvalds@localhost.localdomain To: Benjamin Herrenschmidt cc: "Rafael J. Wysocki" , Jesse Barnes , Linux Kernel Mailing List , Andreas Schwab , Len Brown , Ingo Molnar Subject: Re: Reworking suspend-resume sequence (was: Re: PCI PM: Restore standard config registers of all devices early) In-Reply-To: <1233702327.16867.109.camel@pasglop> Message-ID: References: <200901261904.n0QJ4Q9c016709@hera.kernel.org> <200902032253.42709.rjw@sisk.pl> <1233700390.16867.97.camel@pasglop> <200902032344.22348.rjw@sisk.pl> <1233702327.16867.109.camel@pasglop> User-Agent: Alpine 2.00 (LFD 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 4 Feb 2009, Benjamin Herrenschmidt wrote: > > Wait wait wait ... the -whole- point of the exercise, wether using > local_irq_save or disable_irq, -is- to put the ACPI bit -after- setting > the device in low power state and before the restore on wakeup... You're missing context. ACPI isn't just for the device power settings. It's for the CPU's too, and it's for things like "prepare to sleep". And they all have _different_ requirements. What Rafael is trying to tell you is that we have ACPI-initiated ordering requirements between turning CPU's off, and turning devices off, and he's not willing to change that. > The -one- thing that indeed conflicts here is that we disable nonboot > CPUs earlier. Right ? This. > Now, I doubt that would be a big issue With ACPI, there is no such thing as a "big issue". There are only tons of small horrid details that. And the "big issue" is that all the small details are insane. Linus