From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1754879AbcJaP6V (ORCPT <rfc822;w@1wt.eu>);
        Mon, 31 Oct 2016 11:58:21 -0400
Received: from mail-oi0-f67.google.com ([209.85.218.67]:36035 "EHLO
        mail-oi0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1754537AbcJaP6T (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Mon, 31 Oct 2016 11:58:19 -0400
Subject: Re: [PATCH v2] console: use first console if stdout-path device
 doesn't appear
To: Paul Burton <paul.burton@imgtec.com>,
        Michael Ellerman <mpe@ellerman.id.au>
References: <87zill13z8.fsf@concordia.ellerman.id.au>
 <20161031121455.23280-1-paul.burton@imgtec.com>
Cc: Andreas Schwab <schwab@linux-m68k.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Borislav Petkov <bp@suse.de>, Petr Mladek <pmladek@suse.com>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Tejun Heo <tj@kernel.org>, linux-kernel@vger.kernel.org,
        linuxppc-dev@lists.ozlabs.org
From: Larry Finger <Larry.Finger@lwfinger.net>
Message-ID: <61cdc997-61e8-7f30-ba19-35f692a39458@lwfinger.net>
Date: Mon, 31 Oct 2016 10:58:17 -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: <20161031121455.23280-1-paul.burton@imgtec.com>
Content-Type: text/plain; charset=windows-1252; format=flowed
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On 10/31/2016 07:14 AM, 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.

The patch fails to fix my real PowerPC. I still get a kernel panic for an 
attempt to kill init. This first test was done with 4.9-rc2. I am in the process 
of updating to -rc3 to see if that changes anything. Later today when that build 
finishes, I will report those results.

Larry