From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756457AbbCRNnE (ORCPT ); Wed, 18 Mar 2015 09:43:04 -0400 Received: from mail-wg0-f46.google.com ([74.125.82.46]:34616 "EHLO mail-wg0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755995AbbCRNnC (ORCPT ); Wed, 18 Mar 2015 09:43:02 -0400 Message-ID: <550980E5.8080001@gmail.com> Date: Wed, 18 Mar 2015 14:43:01 +0100 From: Quentin Lambert User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: Dan Carpenter CC: Lidza Louina , devel@driverdev.osuosl.org, Greg Kroah-Hartman , driverdev-devel@linuxdriverproject.org, kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] Staging: dgnc: release the lock before testing for nullity References: <1426684868-24402-1-git-send-email-lambert.quentin@gmail.com> <20150318133651.GS10964@mwanda> In-Reply-To: <20150318133651.GS10964@mwanda> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 18/03/2015 14:36, Dan Carpenter wrote: > This changelog still doesn't make sense so I took a look at the code. > > tty_ldisc_deref() is an unlock function. So this is a lock ordering > bug. What makes you think the original ordering was correct? Who > reported this bug? What are the effects of this bug? I was the one who introduced the ordering change in the first place. I am just trying to fix it because although nobody complained I am not sure of the impact and restoring the previous control flow seems to be the right thing to do.