From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:39764 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727320AbeI1BUT (ORCPT ); Thu, 27 Sep 2018 21:20:19 -0400 Date: Thu, 27 Sep 2018 21:00:34 +0200 From: Greg Kroah-Hartman To: Holger =?iso-8859-1?Q?Hoffst=E4tte?= Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, Lyude Paul , Daniel Vetter , Sean Paul Subject: Re: [PATCH 4.18 74/88] drm/atomic: Use drm_drv_uses_atomic_modeset() for debugfs creation Message-ID: <20180927190034.GA1895@kroah.com> References: <20180927090300.631426620@linuxfoundation.org> <20180927090309.614592493@linuxfoundation.org> <42cbbf9c-3076-0c49-36c2-b6fd09628694@applied-asynchrony.com> <20180927123706.GA23563@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Sender: stable-owner@vger.kernel.org List-ID: On Thu, Sep 27, 2018 at 03:26:37PM +0200, Holger Hoffst�tte wrote: > On 09/27/18 14:37, Greg Kroah-Hartman wrote: > > On Thu, Sep 27, 2018 at 12:43:33PM +0200, Holger Hoffst�tte wrote: > > > On 09/27/18 11:03, Greg Kroah-Hartman wrote: > > > > 4.18-stable review patch. If anyone has any objections, please let me know. > > > > > > > > ------------------ > > > > > > > > From: Lyude Paul > > > > > > > > commit 3c499ea0c662e2f38aafbd4f516b08aab8cfa0e5 upstream. > > > > > > > > As pointed out by Daniel Vetter, we should be usinng > > > > drm_drv_uses_atomic_modeset() for determining whether or not we want to > > > > make the debugfs nodes for atomic instead of checking DRIVER_ATOMIC, as > > > > the former isn't an accurate representation of whether or not the driver > > > > is actually using atomic modesetting internally (even though it might > > > > not be exposing atomic capabilities). > > > > > > > > Signed-off-by: Lyude Paul > > > > Cc: Daniel Vetter > > > > Cc: stable@vger.kernel.org > > > > Reviewed-by: Sean Paul > > > > Link: https://patchwork.freedesktop.org/patch/msgid/20180917173733.21293-1-lyude@redhat.com > > > > Signed-off-by: Greg Kroah-Hartman > > > > > > This patch breaks switching the console to high resolution during boot on my > > > workstation with a Radeon card; it worked fine with 4.18.10 and reverting it > > > fixes the problem: > > > > Is 4.19-rc5 also a problem? > > > > No, 4.19-rc5 with the same config works fine and properly switches the > console during boot. > > Interestingly another machine with i915 chip seemed to work fine with this > patch included (rebooted that one first), so it might well be related to > different motherboard/chipset or the Radeon card (an admittedly old, but > otherwise completely functional fanless r600). > > I'll try to find more clues, but for now that's all I got. Ok, I'll go delete this, but this implies a much deeper problem with the code here. No logic should ever change based on a debugfs file creation failing or succeeding. The error checks here are all not needed at all. I'll work on a patch to clean it up for future kernels... thanks, greg k-h