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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 CAD95C4332D for ; Thu, 19 Mar 2020 10:18:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A02E7206D7 for ; Thu, 19 Mar 2020 10:18:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727031AbgCSKS2 (ORCPT ); Thu, 19 Mar 2020 06:18:28 -0400 Received: from cloudserver094114.home.pl ([79.96.170.134]:50372 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725767AbgCSKS2 (ORCPT ); Thu, 19 Mar 2020 06:18:28 -0400 Received: from 185.80.35.16 (185.80.35.16) (HELO kreacher.localnet) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.341) id 723c13f3574c4ab3; Thu, 19 Mar 2020 11:18:26 +0100 From: "Rafael J. Wysocki" To: Pratik Rajesh Sampat Cc: linux-pm@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, pratik.r.sampat@gmail.com, ego@linux.vnet.ibm.com, dja@axtens.net, Michael Ellerman Subject: Re: [PATCH] cpufreq: powernv: Fix frame-size-overflow in powernv_cpufreq_work_fn Date: Thu, 19 Mar 2020 11:18:26 +0100 Message-ID: <1921198.IfoiWgUDIW@kreacher> In-Reply-To: <20200316135743.57735-1-psampat@linux.ibm.com> References: <20200316135743.57735-1-psampat@linux.ibm.com> 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 On Monday, March 16, 2020 2:57:43 PM CET Pratik Rajesh Sampat wrote: > The patch avoids allocating cpufreq_policy on stack hence fixing frame > size overflow in 'powernv_cpufreq_work_fn' > > Fixes: 227942809b52 ("cpufreq: powernv: Restore cpu frequency to policy->cur on unthrottling") > Signed-off-by: Pratik Rajesh Sampat Any objections or concerns here? If not, I'll queue it up. > --- > drivers/cpufreq/powernv-cpufreq.c | 13 ++++++++----- > 1 file changed, 8 insertions(+), 5 deletions(-) > > diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c > index 56f4bc0d209e..20ee0661555a 100644 > --- a/drivers/cpufreq/powernv-cpufreq.c > +++ b/drivers/cpufreq/powernv-cpufreq.c > @@ -902,6 +902,7 @@ static struct notifier_block powernv_cpufreq_reboot_nb = { > void powernv_cpufreq_work_fn(struct work_struct *work) > { > struct chip *chip = container_of(work, struct chip, throttle); > + struct cpufreq_policy *policy; > unsigned int cpu; > cpumask_t mask; > > @@ -916,12 +917,14 @@ void powernv_cpufreq_work_fn(struct work_struct *work) > chip->restore = false; > for_each_cpu(cpu, &mask) { > int index; > - struct cpufreq_policy policy; > > - cpufreq_get_policy(&policy, cpu); > - index = cpufreq_table_find_index_c(&policy, policy.cur); > - powernv_cpufreq_target_index(&policy, index); > - cpumask_andnot(&mask, &mask, policy.cpus); > + policy = cpufreq_cpu_get(cpu); > + if (!policy) > + continue; > + index = cpufreq_table_find_index_c(policy, policy->cur); > + powernv_cpufreq_target_index(policy, index); > + cpumask_andnot(&mask, &mask, policy->cpus); > + cpufreq_cpu_put(policy); > } > out: > put_online_cpus(); >