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 A1AAAC19F2B for ; Fri, 29 Jul 2022 11:44:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236098AbiG2LoD (ORCPT ); Fri, 29 Jul 2022 07:44:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55550 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236063AbiG2Ln7 (ORCPT ); Fri, 29 Jul 2022 07:43:59 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 54D7787C28 for ; Fri, 29 Jul 2022 04:43:59 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D817D61EDC for ; Fri, 29 Jul 2022 11:43:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DC545C433D6; Fri, 29 Jul 2022 11:43:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1659095038; bh=PlDpUa9kKZeXXUnnE5veinbmwK3klYqqIJ+ubLGpGs4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=F+/xlHV46vb8oTFDjdYlS09pHN1sQnHJbfskwHRvRAZYd4veiUeDSQRxhatsos8SX uNJkMz66b4Bu6hxsLc9m1gVkW8JqmPQAnos1U858RTF3gl1kEwkQ8B4VhlSgrOjK3L +CKmKlCyz8Y561H/fHRbSGnvPaZq5/ofRbn/owXo= Date: Fri, 29 Jul 2022 13:43:55 +0200 From: Greg KH To: Pierre-Louis Bossart Cc: kah.jing.lee@intel.com, linux-kernel@vger.kernel.org, arnd@arndb.de, rafael.j.wysocki@intel.com, tien.sung.ang@intel.com, dinh.nguyen@intel.com, Zhou@kroah.com, Furong , Vinod Koul , Bard Liao Subject: Re: [PATCH v2 1/3] drivers: misc: intel_sysid: Add sysid from arch to drivers Message-ID: References: <20220721123017.416438-1-kah.jing.lee@intel.com> <20220721123149.416618-1-kah.jing.lee@intel.com> <7686403c-7252-ef7a-70fc-040c5ab8cb79@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7686403c-7252-ef7a-70fc-040c5ab8cb79@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 28, 2022 at 11:53:33AM -0500, Pierre-Louis Bossart wrote: > > > On 7/28/22 10:59, Greg KH wrote: > > On Thu, Jul 28, 2022 at 10:37:37AM -0500, Pierre-Louis Bossart wrote: > >> Thanks for the review Greg, > >> > >>>> +static int intel_sysid_probe(struct platform_device *pdev) > >>>> +{ > >>>> + struct intel_sysid *sysid; > >>>> + struct resource *regs; > >>>> + > >>>> + sysid = devm_kzalloc(&pdev->dev, sizeof(struct intel_sysid), > >>>> + GFP_KERNEL); > >>>> + if (!sysid) > >>>> + return -ENOMEM; > >>>> + > >>>> + regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); > >>>> + if (!regs) > >>>> + return -ENXIO; > >>>> + > >>>> + sysid->regs = devm_ioremap_resource(&pdev->dev, regs); > >>>> + if (IS_ERR(sysid->regs)) > >>>> + return PTR_ERR(sysid->regs); > >>>> + > >>>> + platform_set_drvdata(pdev, sysid); > >>>> + > >>>> + return devm_device_add_group(&pdev->dev, &intel_sysid_attr_group); > >>> > >>> You just raced with userspace and lost. Please use the default group > >>> for the platform device. > >>> > >>> I need to go remove this function, it should not be used at all as it is > >>> broken. > >> > >> Can you elaborate on the issue and suggested replacement? > >> > >> We used this function for the SoundWire sysfs based on your review > >> comments (2 years ago?) that we should not muck with kobj, and that > >> function devm_device_add_group() is also used in a probe function. > > > > Use the default_groups pointer in the driver structure. > > did you mean dev_groups? Yes, sorry, that's the correct name. > I am not following the idea, for SoundWire all the attributes are really > device-specific or described by ACPI and cannot be hard-coded in the > driver structure. That's what the is_visible() callback is for in the groups structure, you determine if the attribute is visable or not at runtime, you don't rely on the driver itself to add/remove attributes, that does not scale and again, is racy. thanks, greg k-h