From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: [linux-pm] [RFC PATCH 0/4] save and restore ACPI NVS memory during hibernation Date: Tue, 8 Jul 2008 21:37:53 +0200 Message-ID: <20080708193752.GD8694@ucw.cz> References: <1215051868.5628.32.camel@rzhang-dt.sh.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from gprs189-60.eurotel.cz ([160.218.189.60]:1137 "EHLO spitz.ucw.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754212AbYGIOi3 (ORCPT ); Wed, 9 Jul 2008 10:38:29 -0400 Content-Disposition: inline In-Reply-To: <1215051868.5628.32.camel@rzhang-dt.sh.intel.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Zhang Rui Cc: linux-pm , linux-acpi , linux-kernel Hi! > According to the ACPI spec, ACPI NVS memory region is required to > be saved/restored by OS during hibernation. > > Section 15.3.2 ACPI Spec 3.0b, > "OSPM will call the _PTS control method some time before entering > a sleeping state, to allow the platform???s AML code to update > this memory image before entering the sleeping state. > After the system awakes from an S4 state, OSPM will restore this > memory area and call the _WAK control method to enable the BIOS > to reclaim its memory image." > > This patch set add the mechanism to save/restore ACPI NVS memory > during hibernation. > > Patch 01: call platform_begin before swsusp_shrink_memory. > So that we can allocate enough pages for ACPI NVS memory > before shrink the memory. Why is it neccessary to allocate memory for a copy? We should be able to save ACPI NVS area same way we are saving kernel pages, no? -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html