From mboxrd@z Thu Jan 1 00:00:00 1970 From: Johannes Stezenbach Subject: Re: x86 hibernate, resume with different kernel version Date: Fri, 17 Jun 2016 09:35:00 +0200 Message-ID: <20160617073500.GA9368@sig21.net> References: <20160616100330.GA4954@sig21.net> <20160616190621.GA3849@sig21.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail.sig21.net ([80.244.240.74]:58606 "EHLO mail.sig21.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751711AbcFQHfG (ORCPT ); Fri, 17 Jun 2016 03:35:06 -0400 Content-Disposition: inline In-Reply-To: Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: "Rafael J. Wysocki" Cc: "linux-pm@vger.kernel.org" , the arch/x86 maintainers , Konrad Rzeszutek Wilk On Fri, Jun 17, 2016 at 02:53:28AM +0200, Rafael J. Wysocki wrote: > On Fri, Jun 17, 2016 at 12:00 AM, Rafael J. Wysocki wrote: > > On Thu, Jun 16, 2016 at 9:06 PM, Johannes Stezenbach wrote: > >> On Thu, Jun 16, 2016 at 02:11:48PM +0200, Rafael J. Wysocki wrote: > >>> On Thu, Jun 16, 2016 at 12:03 PM, Johannes Stezenbach wrote: > >>> > it's not important for me but I hibernated kernel v4.5.7 > >>> > and inadvertantly resumed using v4.6.2, and ISTR this > >>> > should work (confirmed by looking into git where I found > >>> > commit cc456c4e7cac3837a86aaa7ca3cb9f488d44d196). > >>> > > >>> > My swap is an LVM volume inside dm-crypt, on boot the kernel read > >>> > the resume image but then immediately reset and invalidated it. > >>> > I'm using Debian sid, the initrd calls /bin/resume from > >>> > klibc-utils package. > >>> > > >>> > So, should this still work? I couldn't find any > >>> > information about it. > >>> > >>> It should in theory, but may not in fact due to bugs discovered > >>> recently. This patch should help: > >>> https://patchwork.kernel.org/patch/9172981/ (it has to be applied to > >>> both the image and boot kernels). > >> > >> I applied it to both the v4.5.7 and v4.6.2 kernels, booted > >> v4.5.7, hibernated, booted v4.6.2 to resume: still resets. > > > > Well, it looks broken now, but it used to work at one point at least. > > I need to investigate a bit when the time permits. > > So I tried 4.6.0 and 4.7-rc3, both with > https://patchwork.kernel.org/patch/9172981/ applied, and it worked for > me. > > On x86-64 there's nothing fundamentally preventing a different kernel > from being used as a boot kernel for resume from hibernation (as long > as it uses the same header format as the image kernel), but > incompatibilities in device drivers are not impossible (although they > shouldn't matter in theory). OK, knowing it should work is enough since the use case is not relly important for me. Thanks, Johannes