From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A62EC43387 for ; Fri, 4 Jan 2019 11:01:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5AE13206C0 for ; Fri, 4 Jan 2019 11:01:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726332AbfADLBw (ORCPT ); Fri, 4 Jan 2019 06:01:52 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:40102 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725958AbfADLBv (ORCPT ); Fri, 4 Jan 2019 06:01:51 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7AA3715AD; Fri, 4 Jan 2019 03:01:51 -0800 (PST) Received: from e107155-lin (e107155-lin.cambridge.arm.com [10.1.196.42]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1EAC43F575; Fri, 4 Jan 2019 03:01:48 -0800 (PST) Date: Fri, 4 Jan 2019 11:01:42 +0000 From: Sudeep Holla To: Viresh Kumar Cc: Valentin Schneider , "Rafael J. Wysocki" , Nishanth Menon , Stephen Boyd , linux-pm@vger.kernel.org, Vincent Guittot , quentin.perret@arm.com, dietmar.eggemann@arm.com, Sudeep Holla , Douglas.Raillard@arm.com, "4 . 20" , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] cpufreq: scpi/scmi: Fix freeing of dynamic OPPs Message-ID: <20190104110142.GA28483@e107155-lin> References: <7dddbeabb434225d9b3d02600ea4a2313622ca26.1546594910.git.viresh.kumar@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7dddbeabb434225d9b3d02600ea4a2313622ca26.1546594910.git.viresh.kumar@linaro.org> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Fri, Jan 04, 2019 at 03:14:33PM +0530, Viresh Kumar wrote: > Since the commit 2a4eb7358aba ("OPP: Don't remove dynamic OPPs from > _dev_pm_opp_remove_table()"), dynamically created OPP aren't > automatically removed anymore by dev_pm_opp_cpumask_remove_table(). This > affects the scpi and scmi cpufreq drivers which no longer free OPPs on > failures or on invocations of the policy->exit() callback. > > Create a generic OPP helper dev_pm_opp_remove_all_dynamic() which can be > called from these drivers instead of dev_pm_opp_cpumask_remove_table(). > > In dev_pm_opp_remove_all_dynamic(), we need to make sure that the > opp_list isn't getting accessed simultaneously from other parts of the > OPP core while the helper is freeing dynamic OPPs, i.e. we can't drop > the opp_table->lock while traversing through the OPP list. And to > accomplish that, this patch also creates _opp_kref_release_unlocked() > which can be called from this new helper with the opp_table lock already > held. > I did test it but since I couldn't reproduce the original issue, my tested-by is not that worth. Anyways the changes look fine to me. Reviewed-by: Sudeep Holla -- Regards, Sudeep