Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757232Ab3GLHSO (ORCPT ); Fri, 12 Jul 2013 03:18:14 -0400 Received: from mail-ob0-f174.google.com ([209.85.214.174]:53393 "EHLO mail-ob0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757132Ab3GLHSL (ORCPT ); Fri, 12 Jul 2013 03:18:11 -0400 MIME-Version: 1.0 In-Reply-To: <20130711221527.547.46447.stgit@srivatsabhat.in.ibm.com> References: <20130711221419.547.69781.stgit@srivatsabhat.in.ibm.com> <20130711221527.547.46447.stgit@srivatsabhat.in.ibm.com> Date: Fri, 12 Jul 2013 12:48:10 +0530 Message-ID: Subject: Re: [PATCH 1/8] cpufreq: Revert commit a66b2e to fix cpufreq regression during suspend/resume From: Viresh Kumar To: "Srivatsa S. Bhat" Cc: rjw@sisk.pl, toralf.foerster@gmx.de, 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 Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2108 Lines: 43 On 12 July 2013 03:45, Srivatsa S. Bhat wrote: > commit a66b2e (cpufreq: Preserve sysfs files across suspend/resume) has > unfortunately caused several things in the cpufreq subsystem to break subtly > after a suspend/resume cycle. > > The intention of that patch was to retain the file permissions of the > cpufreq related sysfs files across suspend/resume. To achieve that, the commit > completely removed the calls to cpufreq_add_dev() and __cpufreq_remove_dev() > during suspend/resume transitions. But the problem is that those functions > do 2 kinds of things: > 1. Low-level initialization/tear-down that are critical to the correct > functioning of cpufreq-core. > 2. Kobject and sysfs related initialization/teardown. > > Ideally we should have reorganized the code to cleanly separate these two > responsibilities, and skipped only the sysfs related parts during > suspend/resume. Since we skipped the entire callbacks instead (which also > included some CPU and cpufreq-specific critical components), cpufreq > subsystem started behaving erratically after suspend/resume. > > So revert the commit to fix the regression. We'll revisit and address the > original goal of that commit separately, since it involves quite a bit of > careful code reorganization and appears to be non-trivial. > > (While reverting the commit, note that another commit f51e1eb "cpufreq: > Fix cpufreq regression after suspend/resume" already reverted part of the > original set of changes. So revert only the remaining ones). > > Cc: stable@vger.kernel.org > Signed-off-by: Srivatsa S. Bhat > --- > > drivers/cpufreq/cpufreq.c | 4 +++- > drivers/cpufreq/cpufreq_stats.c | 6 ++---- > 2 files changed, 5 insertions(+), 5 deletions(-) Acked-by: Viresh Kumar -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/