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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 4C9D9C433E0 for ; Wed, 13 Jan 2021 15:31:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 02F0423383 for ; Wed, 13 Jan 2021 15:31:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727589AbhAMPau (ORCPT ); Wed, 13 Jan 2021 10:30:50 -0500 Received: from mga11.intel.com ([192.55.52.93]:31884 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725943AbhAMPat (ORCPT ); Wed, 13 Jan 2021 10:30:49 -0500 IronPort-SDR: z5lnRgTOfbn2UGq9yJuYzQLNMikUq1RTtfBVxO9woSAqzH/0nPFBNCCFETCL8K4lvT6yogSoxE um/hVgPFdvyw== X-IronPort-AV: E=McAfee;i="6000,8403,9862"; a="174712314" X-IronPort-AV: E=Sophos;i="5.79,344,1602572400"; d="scan'208";a="174712314" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Jan 2021 07:29:03 -0800 IronPort-SDR: G+To7TD1NwReV8AZ0Ts6sehgbYNwcsAcx12eXhai/LP4jqb2Rq3c0C9EB2kCJjiQA7VTxmNgUK vg+5HI5Z6w3Q== X-IronPort-AV: E=Sophos;i="5.79,344,1602572400"; d="scan'208";a="348854662" Received: from smile.fi.intel.com (HELO smile) ([10.237.68.40]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Jan 2021 07:29:01 -0800 Received: from andy by smile with local (Exim 4.94) (envelope-from ) id 1kzi5z-00DDhq-FI; Wed, 13 Jan 2021 17:30:03 +0200 Date: Wed, 13 Jan 2021 17:30:03 +0200 From: Andy Shevchenko To: Heikki Krogerus Cc: Daniel Scally , Felipe Balbi , "Rafael J. Wysocki" , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, linux-acpi@vger.kernel.org Subject: Re: [PATCH v2 1/3] software node: Introduce device_add_software_node() Message-ID: <20210113153003.GR4077@smile.fi.intel.com> References: <20210111141045.14027-1-heikki.krogerus@linux.intel.com> <20210111141045.14027-2-heikki.krogerus@linux.intel.com> <2f552de5-4839-a1e5-3012-c56f9fa3bdd5@gmail.com> <20210113113918.GA2584629@kuha.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210113113918.GA2584629@kuha.fi.intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 13, 2021 at 01:39:18PM +0200, Heikki Krogerus wrote: > On Wed, Jan 13, 2021 at 12:40:03AM +0000, Daniel Scally wrote: > > On 11/01/2021 14:10, Heikki Krogerus wrote: ... > > > +/** > > > + * device_remove_software_node - Remove device's software node > > > + * @dev: The device with the software node. > > > + * > > > + * This function will unregister the software node of @dev. > > > + */ > > > +void device_remove_software_node(struct device *dev) > > > +{ > > > + struct swnode *swnode; > > > + > > > + swnode = dev_to_swnode(dev); > > > + if (!swnode) > > > + return; > > > + > > > + kobject_put(&swnode->kobj); > > > +} > > > +EXPORT_SYMBOL_GPL(device_remove_software_node); > > > > I wonder if this also ought to set dev_fwnode(dev)->secondary back to > > ERR_PTR(-ENODEV)? Actually it's a good question. > We can't do that here unfortunately. Other places still have a > reference to the swnode at this point and they may still need to > access it using the dev_fwnode(dev)->secondary pointer. Yeah, but in this case we potentially leave a dangling pointer when last of the user gone and kobject_put() will call for release. -- With Best Regards, Andy Shevchenko