From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maarten Lankhorst Subject: Re: [PATCH] mutex: fix deadlock injection Date: Wed, 07 Aug 2013 08:22:40 +0200 Message-ID: <5201E7B0.5070802@canonical.com> References: <20130701082221.GA14112@gmail.com> <51D3C4C8.8060701@canonical.com> <20130705062345.GA29487@gmail.com> <51F775B5.201@canonical.com> <20130730084102.GI3008@twins.programming.kicks-ass.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Dave Airlie Cc: Peter Zijlstra , Ingo Molnar , Linus Torvalds , Linux Kernel Mailing List , Thomas Gleixner , Andrew Morton , "dri-devel@lists.freedesktop.org" , Alex Deucher List-Id: dri-devel@lists.freedesktop.org Op 07-08-13 02:05, Dave Airlie schreef: > On Tue, Jul 30, 2013 at 6:41 PM, Peter Zijlstra wrote: >> On Tue, Jul 30, 2013 at 10:13:41AM +0200, Maarten Lankhorst wrote: >>> The check needs to be for > 1, because ctx->acquired is already incremented. >>> This will prevent ww_mutex_lock_slow from returning -EDEADLK and not locking >>> the mutex. It caused a lot of false gpu lockups on radeon with >>> CONFIG_DEBUG_WW_MUTEX_SLOWPATH=y because a function that shouldn't be able >>> to return -EDEADLK did. >>> >>> Cc: Alex Deucher >>> Signed-off-by: Maarten Lankhorst > Should this be merged via Ingo? or will I queue it in my -fixes? > > Dave. > It's in tip:core/urgent, so I imagine you don't need to queue it.