Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751705AbdGaWBv (ORCPT ); Mon, 31 Jul 2017 18:01:51 -0400 Received: from mail-wm0-f45.google.com ([74.125.82.45]:33574 "EHLO mail-wm0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751339AbdGaWBt (ORCPT ); Mon, 31 Jul 2017 18:01:49 -0400 MIME-Version: 1.0 In-Reply-To: <20170731.145151.571917275997786929.davem@davemloft.net> References: <22908.31076.708982.410201@gargle.gargle.HOWL> <22911.25997.495345.538443@gargle.gargle.HOWL> <20170731.145151.571917275997786929.davem@davemloft.net> From: Anatoly Pugachev Date: Tue, 1 Aug 2017 01:01:47 +0300 Message-ID: Subject: Re: strace-4.18 test suite oopses sparc64 4.12 and 4.13-rc kernels To: David Miller Cc: Mikael Pettersson , Sparc kernel list , Linux Kernel list Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2711 Lines: 61 On Tue, Aug 1, 2017 at 12:51 AM, David Miller wrote: > From: Anatoly Pugachev > Date: Tue, 1 Aug 2017 00:48:07 +0300 > >> Aug 01 00:35:11 v215 kernel: sched_xetattr(1527): Oops [#1] >> Aug 01 00:35:11 v215 kernel: CPU: 1 PID: 1527 Comm: sched_xetattr Not >> tainted 4.12.0 #365 >> Aug 01 00:35:11 v215 kernel: task: fff0001231d41340 task.stack: fff000123dfc4000 >> Aug 01 00:35:11 v215 kernel: TSTATE: 0000004411001604 TPC: >> 0000000000a121fc TNPC: 0000000000a12210 Y: 00000000 Not tainted >> Aug 01 00:35:11 v215 kernel: TPC: <__bzero+0x20/0xc0> >> Aug 01 00:35:11 v215 kernel: g0: fff000123dfc7d20 g1: 0000000000000000 >> g2: 0000003000000000 g3: 0000000000000000 >> Aug 01 00:35:11 v215 kernel: g4: fff0001231d41340 g5: fff000123ed08000 >> g6: fff000123dfc4000 g7: 0000000000000030 >> Aug 01 00:35:11 v215 kernel: o0: 0000000000000030 o1: fff000123dfc7e70 >> o2: 0000000000000000 o3: 0000000000000030 >> Aug 01 00:35:11 v215 kernel: o4: fff000123dfc7e70 o5: 000000000000000a >> sp: fff000123dfc75c1 ret_pc: 000000000049b294 >> Aug 01 00:35:11 v215 kernel: RPC: > > Please run gdb on this kernel image and tell it: > > (gdb) x/20i 0x49b294 - 16 > > Thanks. > > I think perhaps one of Al Viro's changes in the bisected commit causes > a branch to either have an overflowed offset field, or get mispatched > to the wrong destination. David, I don't know how to run on a running kernel , but as I understood: root@v215:strace# gzip -dc /boot/vmlinuz-4.12.0 > vmlinux root@v215:strace# gdb -q vmlinux Reading symbols from vmlinux...(no debugging symbols found)...done. (gdb) x/20i 0x49b294 - 16 0x49b284 <_start+619140>: mov -22, %o0 0x49b288 <_start+619144>: sub %i5, %o0, %o0 0x49b28c <_start+619148>: mov %i3, %o2 0x49b290 <_start+619152>: clr %o1 0x49b294 <_start+619156>: call 0xa121b8 <_start+6349240> 0x49b298 <_start+619160>: add %o0, 0x30, %o0 0x49b29c <_start+619164>: cmp %i3, 0 0x49b2a0 <_start+619168>: be %icc, 0x49b20c <_start+619020> 0x49b2a4 <_start+619172>: mov -14, %i0 0x49b2a8 <_start+619176>: rett %i7 + 8 0x49b2ac <_start+619180>: nop 0x49b2b0 <_start+619184>: b,a %xcc, 0x49b2c0 <_start+619200> 0x49b2b4 <_start+619188>: nop 0x49b2b8 <_start+619192>: nop 0x49b2bc <_start+619196>: nop 0x49b2c0 <_start+619200>: save %sp, -176, %sp 0x49b2c4 <_start+619204>: call 0xa136c0 <_start+6354624> 0x49b2c8 <_start+619208>: nop 0x49b2cc <_start+619212>: cmp %i0, 0 0x49b2d0 <_start+619216>: bl,pn %icc, 0x49b318 <_start+619288> 0x49b2d4 <_start+619220>: mov -22, %o0 (gdb)