From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755497AbbCFEyB (ORCPT ); Thu, 5 Mar 2015 23:54:01 -0500 Received: from gate.crashing.org ([63.228.1.57]:48511 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755364AbbCFEx7 (ORCPT ); Thu, 5 Mar 2015 23:53:59 -0500 Message-ID: <1425615522.4636.173.camel@kernel.crashing.org> Subject: Re: [REGRESSION in 3.18][PPC] PA Semi fails to boot after: of/base: Fix PowerPC address parsing hack From: Benjamin Herrenschmidt To: Steven Rostedt Cc: LKML , Grant Likely , Rob Herring , Olof Johansson , linuxppc-dev@lists.ozlabs.org Date: Fri, 06 Mar 2015 15:18:42 +1100 In-Reply-To: <20150305171239.3a8135e6@gandalf.local.home> References: <20150305171239.3a8135e6@gandalf.local.home> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.10-0ubuntu1~14.10.1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2015-03-05 at 17:12 -0500, Steven Rostedt wrote: > A bug in ftrace was reported to me that affects ARM and ARM64 but not > x86. Looking at the code it appears to affect PowerPC as well. So I > booted up my old PA Semi, to give it a try. The last time I booted it > was for a 3.17 kernel. Unfortunately, for 4.0-rc2 it crashed with: Argh. Well, we have one of these here but Michael who owns it is off til Tuesday. Can you shoot me the DT (/proc/device-tree in a tarball) ? Olof, can the DT be updated on this thing or should we add workarounds to Linux if something is really missing ? Cheers, Ben. > Unable to handle kernel paging request for data at address 0x00000000 > Faulting instruction address: 0xc0000000005cef88 > Oops: Kernel access of bad area, sig: 11 [#1] > SMP NR_CPUS=2 PA Semi PWRficient > Modules linked in: > CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.0.0-rc2-test #50 > task: c00000003816cb60 ti: c0000000381a4000 task.ti: c0000000381a4000 > NIP: c0000000005cef88 LR: c00000000007c1a0 CTR: c00000000007c184 > REGS: c0000000381a7a00 TRAP: 0300 Not tainted (4.0.0-rc2-test) > MSR: 9000000000009032 CR: 22000028 XER: 00000000 > DAR: 0000000000000000 DSISR: 40000000 SOFTE: 0 > GPR00: c00000000007c1a0 c0000000381a7c80 c000000000af4b98 0000000000000001 > GPR04: 0000000000000000 0000000000000000 00000000000004ba 000000003d6de000 > GPR08: 0100000000000000 0000000000000000 c0000000381a4080 0000000000000000 > GPR12: 0000000024044042 c00000000ffff300 ffffffffffffffed 0000000000000000 > GPR16: c000000000afb920 c0000000381a4000 c0000000009ad648 c0000000009ae580 > GPR20: c0000000381a4080 c0000000381a4000 c0000000381a4080 c0000000381a4000 > GPR24: c0000000381a4000 c0000000381a4000 c000000000afb880 c0000000381a4000 > GPR28: c0000000009f8790 0000000000000000 c0000000381a4000 c000000000b02168 > NIP [c0000000005cef88] .check_astate+0x28/0x50 > LR [c00000000007c1a0] sleep_common+0x14/0x74 > Call Trace: > [c0000000381a7c80] [c000000000afb880] 0xc000000000afb880 (unreliable) > [c0000000381a7cf0] [c00000000007c1a0] sleep_common+0x14/0x74 > [c0000000381a7d30] [c0000000000130f0] .arch_cpu_idle+0x70/0x160 > [c0000000381a7db0] [c0000000000d6660] .cpu_startup_entry+0x320/0x5a0 > [c0000000381a7ee0] [c000000000034570] .start_secondary+0x290/0x2c0 > [c0000000381a7f90] [c000000000008bfc] start_secondary_prolog+0x10/0x14 > Instruction dump: > 60000000 60000000 7c0802a6 f8010010 f821ff91 60000000 60000000 3d220003 > 39296870 a86d0038 e9290010 7c0004ac <7c004c2c> 0c000000 4c00012c 5463103a > ---[ end trace 40e864a431826b26 ]--- > > I kicked off a ktest bisect, and it came down to this commit: > > commit 746c9e9f92dde2789908e51a354ba90a1962a2eb > Author: Benjamin Herrenschmidt > Date: Fri Nov 14 17:55:03 2014 +1100 > > of/base: Fix PowerPC address parsing hack > > When I revert this from v4.0-rc2, I can successfully boot my PA Semi > again. > > -- Steve