From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756855AbcJMVMM (ORCPT ); Thu, 13 Oct 2016 17:12:12 -0400 Received: from mail-io0-f169.google.com ([209.85.223.169]:36848 "EHLO mail-io0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751393AbcJMVMD (ORCPT ); Thu, 13 Oct 2016 17:12:03 -0400 MIME-Version: 1.0 In-Reply-To: References: <20160802113148.6784f2de@gandalf.local.home> <20160802121305.64307a8a@gandalf.local.home> From: Karol Herbst Date: Thu, 13 Oct 2016 23:12:02 +0200 Message-ID: Subject: Re: mmiotracer hangs the system To: Andy Shevchenko Cc: Steven Rostedt , "linux-kernel@vger.kernel.org" , "Paul E. McKenney" , Ingo Molnar Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org sorry for the delay fixing that bug. I got occupied with other things and didn't really got to the issue again, it is on my todo list as the next item though and I hope I will be able to get a fix ready this weekend. I think I might know where the issue is, but didn't confirm it yet. Again, sorry for the delay. Karol 2016-08-19 22:46 GMT+02:00 Karol Herbst : > Hi again, > > I was able to get a crash/freeze/something while unbinding/binding my > nvidia gpu from nouveau. > > Guess that means something is odd. I will investigate this more over > the weekend. > > 2016-08-19 17:35 GMT+02:00 Andy Shevchenko : >> On Fri, Aug 19, 2016 at 6:08 PM, karol herbst wrote: >>> 2016-08-19 15:02 GMT+02:00 Andy Shevchenko : >>>> On Fri, Aug 19, 2016 at 1:35 PM, karol herbst wrote: >>>>> is there any update on that issue I missed somehow? I really don't >>>>> want to leave the mmiotracer in a state, where it breaks something >>>>> while fixing other issues. >>>> >>>> No updates. I'm busy right now with more priority tasks and revert >>>> works for me. Issue is reproducible in my case 100%. >>>> >>> >>> Is there something I could do with a "normal" haswell desktop system >>> to reproduce this issue? >> >> Try LPSS UART device(s) >> >>> >>> I'll try to play around the next days a bit and maybe I find something >>> that works out here as well. It seems to be related to >>> unmapping-mapping cycles. >> >> That is the only thing I would think of. >> >>> >>> Because if this only happens with the pwm-lpss driver, >> >> It has nothing to do with pwm-lpss since it's a HS UART and served by >> intel-lpss driver. >> >>> it may be >>> really troublesome to debug, because I don't really know the code that >>> well to be sure where the issue might be. >>> >>>> So, I would able to attach dmesg in case it would be helpful. >>>> Otherwise tell me exact instructions how to debug the issue. >>>> >>>> Here you are: >>>> http://pastebin.com/raw/VfTZENt7 >>>> >>>>> But for now, without being able to even reproduce the issue, I can't >>>>> really do much, because the code in the current state looks sane to >>>>> me. Maybe this case includes the mmiotracer cleaning things up and >>>>> arms new region for mmiotracing and that's why it fails? Besides that, >>>>> I have no idea and no way to reproduce this, so I can't help this way. >>>> >>>> Maybe. First thing happened is iounmap(). >> >> >> -- >> With Best Regards, >> Andy Shevchenko