Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752841AbcCGQVo (ORCPT ); Mon, 7 Mar 2016 11:21:44 -0500 Received: from mail-io0-f172.google.com ([209.85.223.172]:34455 "EHLO mail-io0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752538AbcCGQUg convert rfc822-to-8bit (ORCPT ); Mon, 7 Mar 2016 11:20:36 -0500 MIME-Version: 1.0 In-Reply-To: <56DD8E3F.8060004@web.de> References: <20160303233415.GA30194@kroah.com> <56DAB98D.6050305@web.de> <20160305174147.GB14401@kroah.com> <56DC2E27.2080006@web.de> <20160307011419.GB6588@kroah.com> <56DD8E3F.8060004@web.de> Date: Mon, 7 Mar 2016 08:20:35 -0800 X-Google-Sender-Auth: TpU6xUCw7Ymki-X5080hj0yJzOc Message-ID: Subject: Re: Linux 4.4.4 [regression] From: Linus Torvalds To: =?UTF-8?B?SsO2cmctVm9sa2VyIFBlZXR6?= , Dave Airlie , DRI mailing list Cc: Greg KH , Linux Kernel Mailing List , Andrew Morton , stable , lwn@lwn.net, Jiri Slaby , Alex Deucher Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1140 Lines: 29 On Mon, Mar 7, 2016 at 6:20 AM, Jörg-Volker Peetz wrote: > > This same problem with X does happen in 4.5-rc7. And removing the line > introduced by patch b36e52c44ce6728824546d8b5f05b844cede96f1 makes X go again on > my laptop. Ok, so that's dbb17a21c131eca94eb31136eee9a7fe5aff00d9 in mainline. Dave, Alex: that commit makes Jörg-Volker's HP Pavilion dv7 with hybrid graphics (AMD HD 4200 - AMD 5400) unable to run X. No suspend/resume in sight, just starting X hangs. I'd guess it's the "radeon_switcheroo_set_state()" craziness (based on that hybrid graphics thing), but we need to do something since this is a regression. Just revert for now? Or do you have other suggestions for Jörg-Volker to test? Maybe that call to drm_helper_hpd_irq_event() should be purely in the real resume path? Or maybe there is something that the switcheroo code does that just interacts badly with the code in drm_helper_hpd_irq_event()? Deadlock on mode_config.mutex or something? I suspect we just need to revert, but if somebody who knows the code sees some obvious fix, holler quickly, please. Linus