From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751637Ab3GQFGy (ORCPT ); Wed, 17 Jul 2013 01:06:54 -0400 Received: from e23smtp02.au.ibm.com ([202.81.31.144]:60455 "EHLO e23smtp02.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751361Ab3GQFGw (ORCPT ); Wed, 17 Jul 2013 01:06:52 -0400 Message-ID: <51E6258A.3050105@linux.vnet.ibm.com> Date: Wed, 17 Jul 2013 10:33:06 +0530 From: "Srivatsa S. Bhat" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120828 Thunderbird/15.0 MIME-Version: 1.0 To: =?UTF-8?B?VG9yYWxmIEbDtnJzdGVy?= CC: "Rafael J. Wysocki" , viresh.kumar@linaro.org, robert.jarzmik@intel.com, durgadoss.r@intel.com, tianyu.lan@intel.com, lantianyu1986@gmail.com, dirk.brandewie@gmail.com, stern@rowland.harvard.edu, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/8] Cpufreq, cpu hotplug, suspend/resume related fixes References: <20130711221419.547.69781.stgit@srivatsabhat.in.ibm.com> <51DF307B.7060307@linux.vnet.ibm.com> <51E56382.3020609@gmx.de> <2829832.mz5UcF7ZkY@vostro.rjw.lan> In-Reply-To: <2829832.mz5UcF7ZkY@vostro.rjw.lan> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13071704-5490-0000-0000-000003D5B7FE Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/17/2013 03:02 AM, Rafael J. Wysocki wrote: > On Tuesday, July 16, 2013 05:15:14 PM Toralf Förster wrote: >> On 07/12/2013 12:23 AM, Srivatsa S. Bhat wrote: >>> On 07/12/2013 04:03 AM, Rafael J. Wysocki wrote: >>>> On Friday, July 12, 2013 03:45:17 AM Srivatsa S. Bhat wrote: >>>>> >>>>> Hi, >>>> >>>> Hi, >>>> >>>>> Commit a66b2e (cpufreq: Preserve sysfs files across suspend/resume) caused >>>>> some subtle regressions in the cpufreq subsystem during suspend/resume. >>>>> This patchset is aimed at rectifying those problems, by fixing the regression >>>>> as well as achieving the original goal of that commit in a proper way. >>>>> >>>>> Patch 1 reverts the above commit, and is CC'ed to stable. >>>>> >>>>> Patches 2 - 5 reorganize the code and have no functional impact, and can go >>>>> in as general cleanups as well. This reorganization builds a base that the >>>>> rest of the patches will make use of. >>>>> >>>>> Patch 6 and 7 add a mechanism to perform light-weight init/tear-down of CPUs >>>>> in the cpufreq subsystem and finally patch 8 uses it to preserve sysfs files >>>>> across suspend/resume. >>>>> >>>>> All the patches apply on current mainline. >>>>> >>>>> >>>>> Robert, Durgadoss, it would be great if you could try it out and see if it works >>>>> well for your usecase. I tested it locally and cpufreq related files did retain >>>>> their permissions across suspend/resume. Let me know if it works fine in your >>>>> setup too. >>>>> >>>>> And I'd of course appreciate to hear from Dirk, Tianyu and Toralf to know >>>>> whether their systems work fine after: >>>>> a. applying only the first commit (this is what gets backported to stable) >>>>> b. applying all the commits >>>>> >>>>> (Note: I had to use Michael's fix[1] to avoid CPU hotplug deadlock while >>>>> testing this patchset. Though that patch also touches cpufreq subsystem, it >>>>> doesn't affect this patchset in any way and there is absolutely no dependency >>>>> between the two in terms of code. That fix just makes basic CPU hotplug work >>>>> without locking up on current mainline). >>>>> >>>>> [1]. https://lkml.org/lkml/2013/7/10/611 >>>>> >>>>> >>>>> Thank you very much! >>>> >>>> Thanks Srivatsa! >>>> >>>> I'm going to take [1/8] for 3.11 and queue up the rest for 3.12 if people don't >>>> hate them. This way we'll have some more testing coverage before they reach >>>> the mainline hopefully. >>>> >> >> On 07/16/2013 01:25 AM, Rafael J. Wysocki wrote:> On Monday, July 15, 2013 07:38:02 PM Toralf Förster wrote: >>> Sorry, I have no idea what 1#8 means. >> >> sry - here again with full quote of the email : >> >> I applied patch [1/8] on top of v3.11-rc1-8-g47188d3 passes two s2ram/wakeup >> cycles fine and crashed the system at the 3rd attempt / one times just at >> the 4th (blinking power led, no sysrq, ...). >> >> Applying patch 1-8 on top of that tree differs in that way that it >> crashes now the system even at the 1st attempt or at least at the 2nd >> >> My hardware is a ThinkPad T420 with latest BIOS and a 32 bit stable >> Gentoo Linux - FWIW .config attached. > > I think you'll need the fixes first, basically [1/8] from this series and > this: https://patchwork.kernel.org/patch/2827512/ . > > Please try to run with these two things applied only and see how that goes. > In addition to what Rafael suggested above, also try running your kernel with cpufreq completely turned off (CONFIG_CPU_FREQ=n). My patches touch only cpufreq, so this experiment will tell us if your suspend/resume issues are really related to cpufreq or not. If turning off cpufreq also breaks your suspend/resume, then a fresh git-bisect might be the only way to go. Regards, Srivatsa S. Bhat