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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 5BFAAC41514 for ; Mon, 2 Sep 2019 07:29:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 22FAC2377D for ; Mon, 2 Sep 2019 07:29:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729768AbfIBH33 (ORCPT ); Mon, 2 Sep 2019 03:29:29 -0400 Received: from mga14.intel.com ([192.55.52.115]:65312 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729408AbfIBH33 (ORCPT ); Mon, 2 Sep 2019 03:29:29 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 02 Sep 2019 00:29:28 -0700 X-IronPort-AV: E=Sophos;i="5.64,457,1559545200"; d="scan'208";a="186935814" Received: from paasikivi.fi.intel.com ([10.237.72.42]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 02 Sep 2019 00:29:26 -0700 Received: by paasikivi.fi.intel.com (Postfix, from userid 1000) id 6BD8920B09; Mon, 2 Sep 2019 10:29:24 +0300 (EEST) Date: Mon, 2 Sep 2019 10:29:24 +0300 From: Sakari Ailus To: Andy Shevchenko Cc: Petr Mladek , linux-kernel@vger.kernel.org, rafael@kernel.org, linux-acpi@vger.kernel.org, devicetree@vger.kernel.org, Rob Herring Subject: Re: [PATCH v3 05/10] device property: Add a function to obtain a node's prefix Message-ID: <20190902072924.GI5475@paasikivi.fi.intel.com> References: <20190829101043.24963-1-sakari.ailus@linux.intel.com> <20190829101043.24963-6-sakari.ailus@linux.intel.com> <20190830124657.GE2680@smile.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190830124657.GE2680@smile.fi.intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Andy, On Fri, Aug 30, 2019 at 03:46:57PM +0300, Andy Shevchenko wrote: > On Thu, Aug 29, 2019 at 01:10:38PM +0300, Sakari Ailus wrote: > > The prefix is used for printing purpose before a node, and it also works > > as a separator between two nodes. > > > + /* Is this the root node? */ > > + parent = fwnode_get_parent(fwnode); > > + if (!parent) > > + return ""; > > + > > + /* Is this 2nd node from the root? */ > > + parent = fwnode_get_next_parent(parent); > > + if (!parent) > > Can we theoretically have a case when we got parent != NULL and thus taken > reference, while the 2nd one is NULL and we leak reference here (and in all > similar places)? fwnode_get_next_parent() releases that reference unconditionally. -- Sakari Ailus sakari.ailus@linux.intel.com