From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754480AbXLGBaV (ORCPT ); Thu, 6 Dec 2007 20:30:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753025AbXLGBaG (ORCPT ); Thu, 6 Dec 2007 20:30:06 -0500 Received: from simmts12-qfe0.srvr.bell.ca ([206.47.199.141]:40117 "EHLO simmts12-srv.bellnexxia.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752177AbXLGBaE (ORCPT ); Thu, 6 Dec 2007 20:30:04 -0500 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AgAAAOYwWEecIvVD/2dsb2JhbAAI Message-ID: <4758A216.3030401@gmail.com> Date: Thu, 06 Dec 2007 21:29:58 -0400 From: Kevin Winchester User-Agent: Thunderbird 2.0.0.6 (X11/20071022) MIME-Version: 1.0 To: Daniel Walker CC: Ingo Molnar , akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux@bohmer.net, jonathan@jonmasters.org, matthias.kaehlcke@gmail.com Subject: Possible locking issue in viotape.c References: <20071206021857.826386004@mvista.com> <20071206021909.131993721@mvista.com> <20071206102334.GE17299@elte.hu> <1196958847.1568.98.camel@jnielson-xp.ddns.mvista.com> <47588610.5010804@gmail.com> <1196989515.1568.131.camel@jnielson-xp.ddns.mvista.com> In-Reply-To: <1196989515.1568.131.camel@jnielson-xp.ddns.mvista.com> X-Enigmail-Version: 0.95.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Daniel Walker wrote: > > I've posted all the ones I've done so far .. > > ftp://source.mvista.com/pub/dwalker/sem2mutex-2.6.24-rc4/ > > Feel free to review or test them.. I've found it pretty easy to simply > grep for certain class of semaphore usage, check if it's conforming to > the mutex requirements, then convert it or not.. Checking them is > getting to be a habit, so I don't think a list would help me.. However, > someone else might be able to use it.. > Thanks, that helps me not duplicate anything. One of the first ones I was looking at (before your post) was viotape.c, which is in your patch set. However, looking at the uses of the semaphore, I see that on line 409-410 the following code: if (noblock) return count; which seems to ignore the fact that the semaphore has been downed (not to mention the dma buffer and op struct allocations. I think it should be: if (noblock) ret = count; goto free_dma; instead. Do you want to make sure I'm right about that and fold it into your patch? Or have you already submitted your patch (or should it be in a separate patch? Alternatively, I can submit the patch if you don't want to bother with it. -- Kevin Winchester