From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752281AbeC0CE1 (ORCPT ); Mon, 26 Mar 2018 22:04:27 -0400 Received: from mail-pf0-f193.google.com ([209.85.192.193]:45005 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752209AbeC0CEZ (ORCPT ); Mon, 26 Mar 2018 22:04:25 -0400 X-Google-Smtp-Source: AG47ELvuS6fSwOsQ5yuGIU7QEsAqPP2GkZAkLKZX8k9sAWMc9OkGN527Tcm62PeiEhRchntFLPLeiw== Subject: Re: [PATCH] cpufreq: ti-cpufreq: Fix couple of minor issues in probe() To: Suman Anna , Viresh Kumar References: <20180326215244.26304-1-s-anna@ti.com> Cc: "Rafael J. Wysocki" , Dave Gerlach , Tero Kristo , linux-omap@vger.kernel.org, linux-kernel@vger.kernel.org From: Zumeng Chen Message-ID: <5bbd266a-ddc6-296a-dcea-58dc8da6062a@gmail.com> Date: Tue, 27 Mar 2018 10:10:51 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <20180326215244.26304-1-s-anna@ti.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/27/2018 05:52 AM, Suman Anna wrote: > Commit 05829d9431df ("cpufreq: ti-cpufreq: kfree opp_data when > failure") has fixed a memory leak in the failure path, however > kmemleak still keeps reporting a leak even on successful probes. > This is a false-positive and is mostly a result of the opp_data > variable not being stored anywhere in the probe function. The > patch also returned a positive value on the get_cpu_device() > failure instead of a negative value. > > unreferenced object 0xecae4d80 (size 64): > comm "swapper/0", pid 1, jiffies 4294937673 (age 154.420s) > hex dump (first 32 bytes): > 10 40 d9 ee 74 b7 db ee 00 24 ac ec 20 a3 ea c0 .@..t....$.. ... > 00 26 ac ec 00 00 00 00 00 00 00 00 00 00 00 00 .&.............. > backtrace: > [] platform_drv_probe+0x50/0xac > [] driver_probe_device+0x24c/0x330 > [] bus_for_each_drv+0x54/0xb8 > [<2c6f7021>] __device_attach+0xcc/0x13c > [] bus_probe_device+0x88/0x90 > [] device_add+0x38c/0x5b4 > [<6f1af99b>] platform_device_add+0x100/0x220 > [] platform_device_register_full+0xf0/0x104 > [<4d492439>] ti_cpufreq_init+0x44/0x6c > [<81222e89>] do_one_initcall+0x48/0x190 > [<3bebf42a>] kernel_init_freeable+0x1f4/0x2b8 > [<230ad7df>] kernel_init+0x8/0x110 > [<43a165c3>] ret_from_fork+0x14/0x20 > [< (null)>] (null) > [<87288797>] 0xffffffff > > Fix both issues by replacing the previous logic by using the devres > managed API for allocating the opp_data variable, and simplifying > the get_cpu_device() failure return path. > > Fixes: 05829d9431df ("cpufreq: ti-cpufreq: kfree opp_data when failure") > Cc: Zumeng Chen Acked, I'm aware of the false-postive one, this is good to fix both one, thanks~ Cheers, Zumeng > Signed-off-by: Suman Anna > --- > drivers/cpufreq/ti-cpufreq.c | 7 ++----- > 1 file changed, 2 insertions(+), 5 deletions(-) > > diff --git a/drivers/cpufreq/ti-cpufreq.c b/drivers/cpufreq/ti-cpufreq.c > index a099b7bf74cd..7d353a21935b 100644 > --- a/drivers/cpufreq/ti-cpufreq.c > +++ b/drivers/cpufreq/ti-cpufreq.c > @@ -217,7 +217,7 @@ static int ti_cpufreq_probe(struct platform_device *pdev) > if (!match) > return -ENODEV; > > - opp_data = kzalloc(sizeof(*opp_data), GFP_KERNEL); > + opp_data = devm_kzalloc(&pdev->dev, sizeof(*opp_data), GFP_KERNEL); > if (!opp_data) > return -ENOMEM; > > @@ -226,8 +226,7 @@ static int ti_cpufreq_probe(struct platform_device *pdev) > opp_data->cpu_dev = get_cpu_device(0); > if (!opp_data->cpu_dev) { > pr_err("%s: Failed to get device for CPU0\n", __func__); > - ret = ENODEV; > - goto free_opp_data; > + return -ENODEV; > } > > opp_data->opp_node = dev_pm_opp_of_get_opp_desc_node(opp_data->cpu_dev); > @@ -285,8 +284,6 @@ static int ti_cpufreq_probe(struct platform_device *pdev) > > fail_put_node: > of_node_put(opp_data->opp_node); > -free_opp_data: > - kfree(opp_data); > > return ret; > }