From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932826Ab1FQPbl (ORCPT ); Fri, 17 Jun 2011 11:31:41 -0400 Received: from smtp3-g21.free.fr ([212.27.42.3]:48378 "EHLO smtp3-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932419Ab1FQPbk (ORCPT ); Fri, 17 Jun 2011 11:31:40 -0400 Message-ID: <4DFB7352.1040706@free.fr> Date: Fri, 17 Jun 2011 17:31:30 +0200 From: f6bvp User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.17) Gecko/20110501 Mandriva/3.1.10-0.1mdv2010.2 (2010.2) Thunderbird/3.1.10 MIME-Version: 1.0 To: Arnd Bergmann CC: Ralf Baechle , linux-kernel@vger.kernel.org, Linux Netdev List , linux-hams@vger.kernel.org Subject: Re: [AX25] inconsistent lock state References: <4B2CD772.1030106@upmc.fr> <201106171536.15660.arnd@arndb.de> <20110617135147.GA3470@linux-mips.org> <201106171611.10655.arnd@arndb.de> In-Reply-To: <201106171611.10655.arnd@arndb.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Arnd, I will apply your patch with write_lock_bh only following your remark about recursive call. I agree that the error message did not appear systematically when doing what I did i.e. unpluging the ethernet cable from the computer interface. However, I will perform the same a few times and see what happens. Many thanks. Bernard Le 17/06/2011 16:11, Arnd Bergmann a écrit : > On Friday 17 June 2011 15:51:48 Ralf Baechle wrote: >> On Fri, Jun 17, 2011 at 03:36:15PM +0200, Arnd Bergmann wrote: >> >> (Removed Jarek from cc; his email bounces.) >> >>> The message hints that disc_data_lock is aquired with softirqs disabled, >>> but does not itself disable softirqs, which can in rare circumstances >>> lead to a deadlock. >>> >>> Does this fix it? >> If so, drivers/net/hamradio.c, function sp_get() would probably need the >> equivalent fix. Same for drivers/net/ppp_async.c:ap_get() and sp_get() in >> drivers/net/ppp_synctty.c. > It seems that ppp_synctty.c is ok, it uses write_lock_irq() already, > sixpack.c looks like it has the same bug as mkiss. I also realized > after sending out the patch that only the write_lock needs to be > changed to write_lock_bh, while read_lock can leave softirqs enabled > because it can be called recursively. > > Arnd