From mboxrd@z Thu Jan 1 00:00:00 1970 From: f6bvp Subject: Re: [AX25] inconsistent lock state Date: Fri, 17 Jun 2011 17:31:30 +0200 Message-ID: <4DFB7352.1040706@free.fr> References: <4B2CD772.1030106@upmc.fr> <201106171536.15660.arnd@arndb.de> <20110617135147.GA3470@linux-mips.org> <201106171611.10655.arnd@arndb.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Ralf Baechle , linux-kernel@vger.kernel.org, Linux Netdev List , linux-hams@vger.kernel.org To: Arnd Bergmann Return-path: In-Reply-To: <201106171611.10655.arnd@arndb.de> Sender: linux-hams-owner@vger.kernel.org List-Id: netdev.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 =E9crit : > 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 disa= bled, >>> but does not itself disable softirqs, which can in rare circumstanc= es >>> 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_ge= t() 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 -- To unsubscribe from this list: send the line "unsubscribe linux-hams" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html