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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6A2CDC4332F for ; Tue, 22 Nov 2022 08:47:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232465AbiKVIrF (ORCPT ); Tue, 22 Nov 2022 03:47:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49132 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232952AbiKVIrE (ORCPT ); Tue, 22 Nov 2022 03:47:04 -0500 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C79301583B for ; Tue, 22 Nov 2022 00:47:03 -0800 (PST) Received: from dggpemm500023.china.huawei.com (unknown [172.30.72.56]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4NGd7b5LgczqSd9; Tue, 22 Nov 2022 16:43:07 +0800 (CST) Received: from dggpemm500007.china.huawei.com (7.185.36.183) by dggpemm500023.china.huawei.com (7.185.36.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Tue, 22 Nov 2022 16:47:01 +0800 Received: from [10.174.178.174] (10.174.178.174) by dggpemm500007.china.huawei.com (7.185.36.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Tue, 22 Nov 2022 16:47:01 +0800 Subject: Re: [PATCH v3] usb: roles: fix of node refcount leak in usb_role_switch_is_parent() To: Heikki Krogerus CC: , , , References: <20221121144620.4059019-1-yangyingliang@huawei.com> From: Yang Yingliang Message-ID: <3dca37e7-a8d7-eaaa-384b-c70d88aee934@huawei.com> Date: Tue, 22 Nov 2022 16:47:00 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Originating-IP: [10.174.178.174] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpemm500007.china.huawei.com (7.185.36.183) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On 2022/11/22 16:33, Heikki Krogerus wrote: > Hi, > > On Mon, Nov 21, 2022 at 10:46:20PM +0800, Yang Yingliang wrote: >> I got the following report while doing device(mt6370-tcpc) load >> test with CONFIG_OF_UNITTEST and CONFIG_OF_DYNAMIC enabled: >> >> OF: ERROR: memory leak, expected refcount 1 instead of 2, >> of_node_get()/of_node_put() unbalanced - destroy cset entry: >> attach overlay node /i2c/pmic@34 >> >> The 'parent' returned by fwnode_get_parent() with refcount incremented. >> it needs be put after using. >> >> Fixes: 6fadd72943b8 ("usb: roles: get usb-role-switch from parent") >> Suggested-by: Heikki Krogerus > That's not the appropriate tag in this case. I have not suggested > this patch. > >> Signed-off-by: Yang Yingliang >> --- >> v2 -> v3: >> Remove not needed null pointer check. >> >> v1 -> v2: >> Add description to how is the report generated. >> --- >> drivers/usb/roles/class.c | 5 ++++- >> 1 file changed, 4 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c >> index dfaed7eee94f..0650295f261c 100644 >> --- a/drivers/usb/roles/class.c >> +++ b/drivers/usb/roles/class.c >> @@ -106,10 +106,13 @@ usb_role_switch_is_parent(struct fwnode_handle *fwnode) >> struct fwnode_handle *parent = fwnode_get_parent(fwnode); >> struct device *dev; >> >> - if (!parent || !fwnode_property_present(parent, "usb-role-switch")) >> + if (!parent || !fwnode_property_present(parent, "usb-role-switch")) { > Please change that as well like I proposed earlier: > > if (!fwnode_property_present(parent, "usb-role-switch")) { > > You don't need to check the parent separately. Yes, fwnode_property_present() has already checked the parent, the parent check can be removed. Need I add your suggest tag when I send v4 to change it as above. Thanks, Yang > >> + fwnode_handle_put(parent); >> return NULL; >> + } >> >> dev = class_find_device_by_fwnode(role_class, parent); >> + fwnode_handle_put(parent); >> return dev ? to_role_switch(dev) : ERR_PTR(-EPROBE_DEFER); >> } >> > thanks, >