From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753227Ab0KIH73 (ORCPT ); Tue, 9 Nov 2010 02:59:29 -0500 Received: from zone0.gcu-squad.org ([212.85.147.21]:40483 "EHLO services.gcu-squad.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753071Ab0KIH71 (ORCPT ); Tue, 9 Nov 2010 02:59:27 -0500 Date: Tue, 9 Nov 2010 08:59:14 +0100 From: Jean Delvare To: Axel Lin Cc: linux-kernel , Guenter Roeck , Simon Guinot , lm-sensors@lm-sensors.org Subject: Re: [PATCH] hwmon: (gpio-fan) Fix fan_ctrl_init error path Message-ID: <20101109085914.05589cca@endymion.delvare> In-Reply-To: <1289279919.14461.7.camel@mola> References: <1289279919.14461.7.camel@mola> X-Mailer: Claws Mail 3.7.5 (GTK+ 2.20.1; x86_64-unknown-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 Hi Alex, On Tue, 09 Nov 2010 13:18:39 +0800, Axel Lin wrote: > Remove sysfs entries before return -ENODEV. > > Signed-off-by: Axel Lin > --- > drivers/hwmon/gpio-fan.c | 4 +++- > 1 files changed, 3 insertions(+), 1 deletions(-) > > diff --git a/drivers/hwmon/gpio-fan.c b/drivers/hwmon/gpio-fan.c > index aa701a1..d2e66b4 100644 > --- a/drivers/hwmon/gpio-fan.c > +++ b/drivers/hwmon/gpio-fan.c > @@ -388,11 +388,13 @@ static int fan_ctrl_init(struct gpio_fan_data *fan_data, > fan_data->speed_index = get_fan_speed_index(fan_data); > if (fan_data->speed_index < 0) { > err = -ENODEV; > - goto err_free_gpio; > + goto err_remove_sysfs; > } > > return 0; > > +err_remove_sysfs: > + sysfs_remove_group(&pdev->dev.kobj, &gpio_fan_ctrl_group); > err_free_gpio: > for (i = i - 1; i >= 0; i--) > gpio_free(ctrl[i]); This is certainly better than the current situation, however the fact that you need to do this strongly suggests that the initialization order is wrong in the first place. Creating the sysfs attribute should be the last thing done by the function, after all the rest has been successful. Otherwise there is a small window during which user-space can access the attribute but the driver isn't ready to deal with the requests. -- Jean Delvare