From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756323AbbAHV6i (ORCPT ); Thu, 8 Jan 2015 16:58:38 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:35475 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753387AbbAHV6g (ORCPT ); Thu, 8 Jan 2015 16:58:36 -0500 Message-ID: <54AEFD80.5090808@canonical.com> Date: Thu, 08 Jan 2015 16:58:24 -0500 From: Joseph Salisbury User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-Version: 1.0 To: "Deucher, Alexander" CC: "stable@vger.kernel.org" , LKML , "Koenig, Christian" , David Airlie , dri-devel Subject: Re: [Regression][v3.17][3.18][3.19-rc3] drm/radeon: re-enable dpm by default on BTC References: <54ADB86B.10105@canonical.com> <54AEAF92.10507@canonical.com> In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/08/2015 12:48 PM, Deucher, Alexander wrote: >> -----Original Message----- >> From: Joseph Salisbury [mailto:joseph.salisbury@canonical.com] >> Sent: Thursday, January 08, 2015 11:26 AM >> To: Deucher, Alexander >> Cc: stable@vger.kernel.org; LKML; Koenig, Christian; David Airlie; dri-devel >> Subject: Re: [Regression][v3.17][3.18][3.19-rc3] drm/radeon: re-enable dpm >> by default on BTC >> >> On 01/07/2015 09:51 PM, Deucher, Alexander wrote: >>>> -----Original Message----- >>>> From: Joseph Salisbury [mailto:joseph.salisbury@canonical.com] >>>> Sent: Wednesday, January 07, 2015 5:51 PM >>>> To: Deucher, Alexander >>>> Cc: stable@vger.kernel.org; LKML; Koenig, Christian; David Airlie; dri-devel >>>> Subject: [Regression][v3.17][3.18][3.19-rc3] drm/radeon: re-enable dpm >> by >>>> default on BTC >>>> >>>> Hi Alexander, >>>> >>>> A kernel bug report was opened against Ubuntu [0]. After a kernel >>>> bisect, it was found that reverting the following commit resolved this bug: >>>> >>>> commit c08abf11900e19b14dd3a0cc3d105bd74519cd18 >>>> Author: Alex Deucher >>>> Date: Mon Jul 14 12:01:40 2014 -0400 >>>> >>>> drm/radeon: re-enable dpm by default on BTC >>>> >>>> The regression was introduced as of v3.17-rc1 and still exists in >>>> current mainline. It has also made it's way into the stable releases. >>>> >>>> I was hoping to get your feedback, since you are the patch author. Do >>>> you think gathering any additional data will help diagnose this issue, >>>> or would it be best to submit a revert request? >>>> >>> Does revering b2dccf24e77 help? I'd hate to revert this patch because it >> disables power management for a whole family of chips. If it doesn't help I'd >> prefer to just add a quirk to disable it for the specific problematic board. >> Commit b2dccf24e77 was added to mainline as of v3.18-rc1 and was not >> cc'd to stable. We are also seeing this issue in the 3.13.y stable >> kernel, which does not have commit b2dccf24e77 applied. However, we can >> test reverting it in mainline? > Nope. Won't make a difference. The attached patch adds a quirk list for dpm which will fix the issue for the affected boards. > > Alex Thanks again for the patch, Alex. The bug reporter has tested a 3.16 kernel with the patch and says it fixes the bug. > >>> Alex >>> >>>> Thanks, >>>> >>>> Joe >>>> >>>> [0] http://pad.lv/1386534