From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758944AbXGXPTb (ORCPT ); Tue, 24 Jul 2007 11:19:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753742AbXGXPTX (ORCPT ); Tue, 24 Jul 2007 11:19:23 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:55457 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752866AbXGXPTW (ORCPT ); Tue, 24 Jul 2007 11:19:22 -0400 From: "Rafael J. Wysocki" To: "Huang, Ying" Subject: Re: [PATCH 0/2] Kexec jump: The first step to kexec base hibernation Date: Tue, 24 Jul 2007 17:27:34 +0200 User-Agent: KMail/1.9.5 Cc: "Eric W. Biederman" , "Andrew Morton" , "Pavel Machek" , nigel@nigel.suspend2.net, "Jeremy Maitin-Shepard" , linux-kernel@vger.kernel.org, linux-pm@lists.linux-foundation.org, "Kexec Mailing List" References: <9D7649D18729DE4BB2BD7B494F7FEDC236CF66@pdsmsx415.ccr.corp.intel.com> In-Reply-To: <9D7649D18729DE4BB2BD7B494F7FEDC236CF66@pdsmsx415.ccr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200707241727.35589.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tuesday, 24 July 2007 16:00, Huang, Ying wrote: > >From: Rafael J. Wysocki [mailto:rjw@sisk.pl] > >This is not the point. There are memory regions that you should not > _restore_, > >because that will cause harm. > > > >> On x86_64, there is another usage of nosave during processing E820 > >> memory map. But I don't know why the memory region other than > E820_RAM > >> are marked as nosave. I think only the memory region of type E820_RAM > >> will be thought of normal memory, others will be thought as reserved. > Is > >> it sufficient just to check whether the page is reserved? > > > >No, it's not. > > The "/proc/iomem" records information of all memory regions including > "normal RAM" and all kinds of reserved regions, which is backed by > iomem_resource. On x86_64, it is initialized in the exact same way as > nosave region initialization. > > I think maybe we can replace the "nosave region" concepts with > "iomem_resource" (maybe need some enhancement). Yes, I think that might be done. Geetings, Rafael -- "Premature optimization is the root of all evil." - Donald Knuth