Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761685AbdLSJ7f (ORCPT ); Tue, 19 Dec 2017 04:59:35 -0500 Received: from mail-wr0-f178.google.com ([209.85.128.178]:36725 "EHLO mail-wr0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757754AbdLSJ73 (ORCPT ); Tue, 19 Dec 2017 04:59:29 -0500 X-Google-Smtp-Source: ACJfBov3GfrZpdSkv87E3tqtaVXCgtXHlbqGz3VfJN03Xe/5kwKtjryb7JfO2Pry+Xv3G8IhO1LAbg== Date: Tue, 19 Dec 2017 10:59:25 +0100 From: Daniel Vetter To: Linus Torvalds Cc: Peter Zijlstra , LKML , DRI Development , Intel Graphics Development , Tvrtko Ursulin , Marta Lofstedt , Byungchul Park , Ingo Molnar , Tejun Heo , Kees Cook , Thomas Gleixner , Shaohua Li , Andrew Morton , Jens Axboe , Greg Kroah-Hartman , Jonathan Corbet , Oleg Nesterov , Daniel Vetter , Daniel Vetter Subject: Re: [PATCH] kthread: finer-grained lockdep/cross-release completion Message-ID: <20171219095925.GY26573@phenom.ffwll.local> Mail-Followup-To: Linus Torvalds , Peter Zijlstra , LKML , DRI Development , Intel Graphics Development , Tvrtko Ursulin , Marta Lofstedt , Byungchul Park , Ingo Molnar , Tejun Heo , Kees Cook , Thomas Gleixner , Shaohua Li , Andrew Morton , Jens Axboe , Greg Kroah-Hartman , Jonathan Corbet , Oleg Nesterov , Daniel Vetter References: <20171207100849.407-1-daniel.vetter@ffwll.ch> <20171208105419.jdzene5wrsriwm2n@hirez.programming.kicks-ass.net> <20171211091928.cpw3srz2rddmruxj@phenom.ffwll.local> <20171218071159.GW26573@phenom.ffwll.local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Operating-System: Linux phenom 4.13.0-1-amd64 User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1543 Lines: 36 On Mon, Dec 18, 2017 at 09:42:13AM -0800, Linus Torvalds wrote: > On Sun, Dec 17, 2017 at 11:11 PM, Daniel Vetter wrote: > > > > This didn't seem to have made it into -rc4. Anything needed to get it > > going? > > Do you actually see the problem in -rc4? > > Because we ended up removing the cross-release checking due to other > developers complaining. It seemed to need a lot more work before it > was ready. > > So I suspect the patch is simply not relevant any more (even if it's > not necessarily wrong either). Awww ... I like the cross release stuff, it's catching lots of good bugs for us - writing a gpu memory manager that's supposed to interface with the core one ain't the simplest thing to get right. That's also why we're going around and fixing up fallout (we've worked on the worker annotations for 4.14 too). I guess next release, hopefully. I think between 4.14 and 4.15 attemps cross-release spotted around 5 or so genuine deadlocks in i915 code. And at least right now, with the current set of fixups our CI runs are splat-free. So at least a Kconfig option would be nice, to be able to enable it easily when you want to. Wrt us not noticing: Getting the patches in through normal means takes too long, so we constantly carry arounda bunch of fixup patches to address serious issues that block CI (no lockdep is no good CI). That's why we won't immediately notice when an issue is resolved some other way. Cheers, Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch