Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752440AbdFNVcr (ORCPT ); Wed, 14 Jun 2017 17:32:47 -0400 Received: from mail-pg0-f53.google.com ([74.125.83.53]:34550 "EHLO mail-pg0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752004AbdFNVcq (ORCPT ); Wed, 14 Jun 2017 17:32:46 -0400 Subject: Re: Qemu crashes in -next due to 'of: remove *phandle properties from expanded device tree' To: Guenter Roeck , Frank Rowand References: <20170614192638.GA15210@roeck-us.net> Cc: linux-kernel@vger.kernel.org, Rob Herring From: Frank Rowand Message-ID: <5941AB4E.3070804@gmail.com> Date: Wed, 14 Jun 2017 14:31:58 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 MIME-Version: 1.0 In-Reply-To: <20170614192638.GA15210@roeck-us.net> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2811 Lines: 73 Hi Guenter, Thanks for reporting this. On 06/14/17 12:26, Guenter Roeck wrote: > Hi Frank, > > your commit 'of: remove *phandle properties from expanded device tree' in > -next causes several of my ppc qemu tests to crash. Looking into qemu, it > sets "linux,phandle" properties for the mpic and for other devices. > > The crashes are along the line of > > ------------[ cut here ]------------ > kernel BUG at arch/powerpc/platforms/85xx/corenet_generic.c:50! > Oops: Exception in kernel mode, sig: 5 [#1] > SMP NR_CPUS=32 > NUMA > CoreNet Generic > Modules linked in: > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.12.0-rc5-next-20170614 #1 > task: c000000000ad8cc0 task.stack: c000000000bec000 > NIP: c000000000a8ca7c LR: c000000000a8ca6c CTR: c000000000a8ca20 > REGS: c000000000befb90 TRAP: 0700 Not tainted (4.12.0-rc5-next-20170614) > MSR: 0000000080021000 > CR: 22000042 XER: 00000000 > SOFTE: 0 > GPR00: c000000000a8ca6c c000000000befe10 c000000000befa00 0000000000000000 > GPR04: 0000000000000000 c000000000ac8458 c000000000ac8438 c000000000830658 > GPR08: 0000000000000001 0000000000000001 0000000000000000 0000000000009531 > GPR12: 0000000022000022 c00000003fff1000 0000000000000000 0000000000000000 > GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > GPR24: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > GPR28: c000000000000300 c00000003fff2cc0 c000000000ac06e0 c000000000ac06e0 > NIP [c000000000a8ca7c] .corenet_gen_pic_init+0x5c/0x90 > LR [c000000000a8ca6c] .corenet_gen_pic_init+0x4c/0x90 > Call Trace: > [c000000000befe10] [c000000000a8ca6c] .corenet_gen_pic_init+0x4c/0x90 > (unreliable) > [c000000000befe80] [c000000000a832f8] .init_IRQ+0x34/0x4c > [c000000000befef0] [c000000000a7fc88] .start_kernel+0x2fc/0x500 > [c000000000beff90] [c000000000000554] start_here_common+0x1c/0x48 > Instruction dump: > e8aa0068 39088268 39407002 38600000 7fa54800 39205002 7caa4f9e 4bffe9e9 > 60000000 2c230000 7d200026 55291ffe <0b090000> 4bfff335 60000000 3ca2ffdd > random: 0x600000003d220004 get_random_bytes called with crng_init=0 > ---[ end trace 0000000000000000 ]--- > > and are caused by the kernel not finding the mpic node anymore. > > Any idea how to solve the problem ? The BUG() is triggered if mpic_alloc() returns NULL. I looked through mpic_alloc(), and the functions that it calls, and nothing is jumping out as being related to phandles. Can you add some printks to mpic_alloc() to determine what problem is causing it to return NULL? Can you also include the console messages before the "[ cut here ]" line? -Frank > > Bisect log is attached. > > Thanks, > Guenter < snip >