From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754318AbZKCWpG (ORCPT ); Tue, 3 Nov 2009 17:45:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751493AbZKCWpG (ORCPT ); Tue, 3 Nov 2009 17:45:06 -0500 Received: from smtp1.linux-foundation.org ([140.211.169.13]:58155 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751253AbZKCWpF (ORCPT ); Tue, 3 Nov 2009 17:45:05 -0500 Date: Tue, 3 Nov 2009 14:44:01 -0800 From: Andrew Morton To: Sergei Shtylyov Cc: linux-kernel@vger.kernel.org, david-b@pacbell.net, Greg KH , Kay Sievers , Tejun Heo Subject: Re: [PATCH] gpiolib: fix device_create() result check Message-Id: <20091103144401.6fa4e130.akpm@linux-foundation.org> In-Reply-To: <200910202035.23981.sshtylyov@ru.mvista.com> References: <200910202035.23981.sshtylyov@ru.mvista.com> X-Mailer: Sylpheed 2.4.8 (GTK+ 2.12.9; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 20 Oct 2009 20:35:23 +0400 Sergei Shtylyov wrote: > In case of failure, device_create() returns not NULL but the error code. > The current code checks for non-NULL though which causes kernel oops in > sysfs_create_group() when device_create() fails. Check for error using > IS_ERR() and propagate the error value using PTR_ERR() instead of fixed > -ENODEV code returned now... Does anyone notice any missing information here? /** * device_create - creates a device and registers it with sysfs * @class: pointer to the struct class that this device should be registered to * @parent: pointer to the parent struct device of this new device, if any * @devt: the dev_t for the char device to be added * @drvdata: the data to be added to the device for callbacks * @fmt: string for the device's name * * This function can be used by char device classes. A struct device * will be created in sysfs, registered to the specified class. * * A "dev" file will be created, showing the dev_t for the device, if * the dev_t is not 0,0. * If a pointer to a parent struct device is passed in, the newly created * struct device will be a child of that device in sysfs. * The pointer to the struct device will be returned from the call. * Any further sysfs files that might be required can be created using this * pointer. * * Note: the struct class passed to this function must have previously * been created with a call to class_create(). */ Why do we do this to ourselves?