Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756744AbcJTFzN (ORCPT ); Thu, 20 Oct 2016 01:55:13 -0400 Received: from mail-it0-f68.google.com ([209.85.214.68]:35383 "EHLO mail-it0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752735AbcJTFzM (ORCPT ); Thu, 20 Oct 2016 01:55:12 -0400 To: LKML , Paul Burton , Andrew Morton , Thorsten Leemhuis From: Larry Finger Subject: Regression in 4.9-rc1 for PPC32 - bisected to commit 05fd007e4629 Message-ID: <2ccf74f5-5fa2-2f47-ade1-69addc79c40b@lwfinger.net> Date: Thu, 20 Oct 2016 00:55:10 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2006 Lines: 62 Kernel 4.9-rc1 fails to boot on my PowerBook G4 Aluminum (32-bit PowerPC) with the following splat: Kernel Panic - not synching: Attempted to kill init: exitcode = 0x00000200 Call trace: dump_stack+0x24/0x34 (unreliable) panic+0x110/0x2ac do_exit+0x464/0x834 do_group_exit+0x84/0xac __wake_up_parent+0x0/0x34 ret_from_syscall+0x0/0x40 As the panic happens very early, I was not able to capture the output, thus the above was entered by hand. The problem was bisected to commit 05fd007e4629 ("console: don't prefer first registered if DT specifies stdout-path"). Examining that patch and testing the various hunks, I found that the system booted fine when I eliminated the hunk at --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -2077,6 +2077,8 @@ void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align)) name = of_get_property(of_aliases, "stdout", NULL); if (name) of_stdout = of_find_node_opts_by_path(name, &of_stdout_options); + if (of_stdout) + console_set_by_of(); } if (!of_aliases) Similarly, it would boot if I eliminated the hunk at --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -2647,7 +2658,7 @@ void register_console(struct console *newcon) * didn't select a console we take the first one * that registers here. */ - if (preferred_console < 0) { + if (preferred_console < 0 && !of_specified_console) { if (newcon->index < 0) newcon->index = 0; if (newcon->setup == NULL || The problem happens when of_specified_console is true, and the code following the modified if statement above is not executed. In my .config, CONFIG_OF=y. As always, I will be happy to test any fixes. Thanks, Larry -- If I was stranded on an island and the only way to get off the island was to make a pretty UI, I’d die there. Linus Torvalds