From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mailout4.samsung.com ([203.254.224.34]:32190 "EHLO mailout4.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727316AbeH3C67 (ORCPT ); Wed, 29 Aug 2018 22:58:59 -0400 MIME-version: 1.0 Content-transfer-encoding: 8BIT Content-type: text/plain; charset="UTF-8" Message-id: <5B87255F.80207@samsung.com> Date: Thu, 30 Aug 2018 07:59:43 +0900 From: Chanwoo Choi To: Bartlomiej Zolnierkiewicz Cc: myungjoo.ham@samsung.com, kyungmin.park@samsung.com, rafael.j.wysocki@intel.com, chanwoo@kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH] PM / devfreq: Add new name attribute for sysfs In-reply-to: <3263263.FggQa7iA9D@amdc3058> References: <1535528046-18835-1-git-send-email-cw00.choi@samsung.com> <3263263.FggQa7iA9D@amdc3058> Sender: stable-owner@vger.kernel.org List-ID: Hi Bartlomiej, On 2018년 08월 29일 21:50, Bartlomiej Zolnierkiewicz wrote: > > Hi Chanwoo, > > On Wednesday, August 29, 2018 04:34:06 PM Chanwoo Choi wrote: >> commit 4585fbcb5331 ("PM / devfreq: Modify the device name as devfreq(X) for >> sysfs") changed the node name to devfreq(x). After this commit, it is not >> possible to get the device name through /sys/class/devfreq/devfreq(X)/*. >> >> Add new name attribute in order to get device name. > > Could you please describe the issue encountered in more detail > (what the old device name is needed for)? You can check it on mail thread[1]. [1] https://lkml.org/lkml/2018/5/8/1042 > >> Cc: stable@vger.kernel.org >> Fixes: 4585fbcb5331 ("PM / devfreq: Modify the device name as devfreq(X) for sysfs") >> Signed-off-by: Chanwoo Choi >> --- >> drivers/devfreq/devfreq.c | 11 +++++++++++ >> include/linux/devfreq.h | 3 +++ >> 2 files changed, 14 insertions(+) >> >> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c >> index 4c49bb1330b5..2145563d5ee5 100644 >> --- a/drivers/devfreq/devfreq.c >> +++ b/drivers/devfreq/devfreq.c >> @@ -620,6 +620,9 @@ struct devfreq *devfreq_add_device(struct device *dev, >> } >> devfreq->max_freq = devfreq->scaling_max_freq; >> >> + devfreq->name = dev_name(devfreq->dev.parent); > > It seems that 'dev' can be used instead of 'devfreq->dev.parent'. devfreq->dev.parent is same with dev. it doesn't matter. > >> + if (IS_ERR_OR_NULL(devfreq->name)) > > Error values are not encoded into pointer returned by dev_name() > (drivers/base/ code is only checking for pointer being NULL). OK. I'll just check whether NULL or not. > >> + return -EINVAL; > > This leaks 'devfreq' object and doesn't encode return value into > pointer returned by devfreq_add_device(), it should be replaced by: Right. I'll fix it. > > err = -EINVAL; > goto err_dev; > >> dev_set_name(&devfreq->dev, "devfreq%d", >> atomic_inc_return(&devfreq_no)); >> err = device_register(&devfreq->dev); > > Best regards, > -- > Bartlomiej Zolnierkiewicz > Samsung R&D Institute Poland > Samsung Electronics > > > -- Best Regards, Chanwoo Choi Samsung Electronics