From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: [patch] hibernation: utilize ACPI hardware signature Date: Wed, 2 Jan 2008 15:12:53 +0100 Message-ID: <200801021512.54140.rjw@sisk.pl> References: <1199257162.14632.4.camel@sli10-desk.sh.intel.com> <62e5edd40801020208s268aeacbj96481f5a317b8ea7@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from ogre.sisk.pl ([217.79.144.158]:41595 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752559AbYABOK6 convert rfc822-to-8bit (ORCPT ); Wed, 2 Jan 2008 09:10:58 -0500 In-Reply-To: <62e5edd40801020208s268aeacbj96481f5a317b8ea7@mail.gmail.com> Content-Disposition: inline Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Erik =?iso-8859-15?q?Andr=E9n?= Cc: Shaohua Li , pm list , linux acpi , Len Brown On Wednesday, 2 of January 2008, Erik Andr=E9n wrote: > Hi, >=20 > 2008/1/2, Shaohua Li : > > > > ACPI defines a hardware signature. BIOS calculates the signature > > according to hardware configure, if hardware changes, the signature= will > > change, in this case, S4 resume should fail. > > > > Signed-off-by: Shaohua Li > > --- >=20 >=20 > Would it be possible to extend this mechanism to prevent the followin= g > scenario: >=20 > 1. Linux image A is suspended to disk > 2. Linux image B is booted and various changes to the system are done= =2E > 3. Linux image B is shut down > 4. Linux image A is booted, restoring the suspend to disk image. > 5. Chaos is ensured as the file system state is changed in regard to = how > linux image A expects it. >=20 > Correct behaviour would naturally be that image A detects that change= s have > been made under its feet and proceed to perform a normal boot instead= of > resuming the stored suspend-to-disk image. It should be possible in theory. > Is there another mechanism preventing this? Not at the kernel level, but you can prevent this from happening by run= ning mkswap on all swap spaces that refuse to come up after a fresh boot. Greetings, Rafael - To unsubscribe from this list: send the line "unsubscribe linux-acpi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html