From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:45202 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752322AbdAXIED (ORCPT ); Tue, 24 Jan 2017 03:04:03 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Chanwoo Choi , "Rafael J. Wysocki" Subject: [PATCH 4.9 112/130] PM / devfreq: Fix the bug of devfreq_add_device when governor is NULL Date: Tue, 24 Jan 2017 08:55:52 +0100 Message-Id: <20170124075539.517002090@linuxfoundation.org> In-Reply-To: <20170124075534.905042535@linuxfoundation.org> References: <20170124075534.905042535@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chanwoo Choi commit 73613b16cb5c5d5a659fc8832eff99eead3f9afb upstream. This patch fixes the bug of devfreq_add_device(). The devfreq device must have the default governor. If find_devfreq_governor() returns error, devfreq_add_device() fail to add the devfreq instance. Fixes: 1b5c1be2c88e (PM / devfreq: map devfreq drivers to governor using name) Signed-off-by: Chanwoo Choi Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/devfreq/devfreq.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -593,11 +593,16 @@ struct devfreq *devfreq_add_device(struc list_add(&devfreq->node, &devfreq_list); governor = find_devfreq_governor(devfreq->governor_name); - if (!IS_ERR(governor)) - devfreq->governor = governor; - if (devfreq->governor) - err = devfreq->governor->event_handler(devfreq, - DEVFREQ_GOV_START, NULL); + if (IS_ERR(governor)) { + dev_err(dev, "%s: Unable to find governor for the device\n", + __func__); + err = PTR_ERR(governor); + goto err_init; + } + + devfreq->governor = governor; + err = devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_START, + NULL); if (err) { dev_err(dev, "%s: Unable to start governor for the device\n", __func__);