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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no 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 C7C98C4BA24 for ; Wed, 26 Feb 2020 21:39:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A6A0124656 for ; Wed, 26 Feb 2020 21:39:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727716AbgBZVja (ORCPT ); Wed, 26 Feb 2020 16:39:30 -0500 Received: from cloudserver094114.home.pl ([79.96.170.134]:52181 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727552AbgBZVja (ORCPT ); Wed, 26 Feb 2020 16:39:30 -0500 Received: from 79.184.237.30.ipv4.supernova.orange.pl (79.184.237.30) (HELO kreacher.localnet) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.341) id 533bfd923ca1b9ab; Wed, 26 Feb 2020 22:39:27 +0100 From: "Rafael J. Wysocki" To: Linux PM Cc: "Rafael J. Wysocki" , Viresh Kumar , Srinivas Pandruvada , LKML , Artem Bityutskiy Subject: [PATCH] cpufreq: Fix policy initialization for internal governor drivers Date: Wed, 26 Feb 2020 22:39:27 +0100 Message-ID: <3873122.F9s1CIEcb3@kreacher> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rafael J. Wysocki Before commit 1e4f63aecb53 ("cpufreq: Avoid creating excessively large stack frames") the initial value of the policy field in struct cpufreq_policy set by the driver's ->init() callback was implicitly passed from cpufreq_init_policy() to cpufreq_set_policy() if the default governor was neither "performance" nor "powersave". After that commit, however, cpufreq_init_policy() must take that case into consideration explicitly and handle it as appropriate, so make that happen. Fixes: 1e4f63aecb53 ("cpufreq: Avoid creating excessively large stack frames") Link: https://lore.kernel.org/linux-pm/39fb762880c27da110086741315ca8b111d781cd.camel@gmail.com/ Reported-by: Artem Bityutskiy Cc: 5.4+ # 5.4+ Signed-off-by: Rafael J. Wysocki --- Note that I'm going to fast-track this patch for 5.6-rc4 which means that it will go into my linux-next branch as soon as it shows up in the lists. Thanks and sorry for the breakage! --- drivers/cpufreq/cpufreq.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) Index: linux-pm/drivers/cpufreq/cpufreq.c =================================================================== --- linux-pm.orig/drivers/cpufreq/cpufreq.c +++ linux-pm/drivers/cpufreq/cpufreq.c @@ -1076,9 +1076,17 @@ static int cpufreq_init_policy(struct cp pol = policy->last_policy; } else if (def_gov) { pol = cpufreq_parse_policy(def_gov->name); - } else { - return -ENODATA; + /* + * In case the default governor is neiter "performance" + * nor "powersave", fall back to the initial policy + * value set by the driver. + */ + if (pol == CPUFREQ_POLICY_UNKNOWN) + pol = policy->policy; } + if (pol != CPUFREQ_POLICY_PERFORMANCE && + pol != CPUFREQ_POLICY_POWERSAVE) + return -ENODATA; } return cpufreq_set_policy(policy, gov, pol);