Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S945852AbcJaTVf (ORCPT ); Mon, 31 Oct 2016 15:21:35 -0400 Received: from mail-oi0-f68.google.com ([209.85.218.68]:33613 "EHLO mail-oi0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S945744AbcJaTVd (ORCPT ); Mon, 31 Oct 2016 15:21:33 -0400 Subject: Re: [PATCH v2] console: use first console if stdout-path device doesn't appear To: Paul Burton , Michael Ellerman References: <87zill13z8.fsf@concordia.ellerman.id.au> <20161031121455.23280-1-paul.burton@imgtec.com> <1593250.MZpe3pfUW6@np-p-burton> Cc: Andreas Schwab , Andrew Morton , Borislav Petkov , Petr Mladek , Sergey Senozhatsky , Tejun Heo , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org From: Larry Finger Message-ID: <8c0538ec-6922-3c43-d944-8ac9cd57a708@lwfinger.net> Date: Mon, 31 Oct 2016 14:21:30 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <1593250.MZpe3pfUW6@np-p-burton> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 928 Lines: 20 On 10/31/2016 10:50 AM, Paul Burton wrote: > On Monday, 31 October 2016 12:14:55 GMT Paul Burton wrote: >> If a device tree specified a preferred device for kernel console output >> via the stdout-path or linux,stdout-path chosen node properties there's >> no guarantee that it will have specified a device for which we have a >> driver. It may also be the case that we do have a driver but it doesn't >> call of_console_check() to register as a preferred console (eg. offb >> driver as used on powermac systems). In these cases try to ensure that >> we provide some console output by enabling the first usable registered >> console, which we keep track of with the of_fallback_console variable. >> >> Tested in QEMU with a PowerPC pseries_defconfig kernel. > > Actually whilst this fixes the output in QEMU it has other problems. I'm still > digging... As expected, it does n ot work with 4.9-rc3 on the real PowerPC. Larry