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 CCA0DC33CA2 for ; Fri, 10 Jan 2020 12:22:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8E1272077C for ; Fri, 10 Jan 2020 12:22:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728079AbgAJMWe (ORCPT ); Fri, 10 Jan 2020 07:22:34 -0500 Received: from foss.arm.com ([217.140.110.172]:43746 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727937AbgAJMWe (ORCPT ); Fri, 10 Jan 2020 07:22:34 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A8A951063; Fri, 10 Jan 2020 04:22:33 -0800 (PST) Received: from bogus (e103737-lin.cambridge.arm.com [10.1.197.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A5AB23F534; Fri, 10 Jan 2020 04:22:32 -0800 (PST) Date: Fri, 10 Jan 2020 12:22:26 +0000 From: Sudeep Holla To: Viresh Kumar Cc: Arnd Bergmann , Vincent Guittot , Jassi Brar , "linux-kernel@vger.kernel.org" , Linux ARM , Sudeep Holla Subject: Re: [PATCH] firmware: arm_scmi: Make scmi core independent of transport type Message-ID: <20200110122226.GA45077@bogus> References: <5c545c2866ba075ddb44907940a1dae1d823b8a1.1575019719.git.viresh.kumar@linaro.org> <20200109091613.fx2ggmmjvgjempks@vireshk-i7> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200109091613.fx2ggmmjvgjempks@vireshk-i7> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 09, 2020 at 02:46:13PM +0530, Viresh Kumar wrote: > On 09-01-20, 09:18, Arnd Bergmann wrote: > > > +static int mailbox_chan_free(int id, void *p, void *data) > > > +{ > > > + struct scmi_chan_info *cinfo = p; > > > + struct scmi_mailbox *smbox = cinfo->transport_info; > > > + > > > + if (!IS_ERR_OR_NULL(smbox->chan)) { > > > + mbox_free_channel(smbox->chan); > > > + cinfo->transport_info = NULL; > > > + smbox->chan = NULL; > > > + smbox->cinfo = NULL; > > > + } > > > > There is something wrong if smbox->chan can be be one of > > three things (a valid pointer, a NULL pointer, or an error value). > > > > I see this is a preexisting problem, but please add a patch to > > make it consistently use either NULL pointers or error codes > > and remove all instances of IS_ERR_OR_NULL() from this > > subsystem. > > This isn't a subsystem problem actually. mbox_request_channel() never > returns NULL on error. > > @Sudeep, do we really need the IS_ERR_OR_NULL() check in > scmi_mbox_free_channel() helper ? Or can it just be IS_ERR() ? > It can be just IS_ERR, just not noticed it so far I believe. -- Regards, Sudeep