From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933315AbdCJSTI (ORCPT ); Fri, 10 Mar 2017 13:19:08 -0500 Received: from mx1.redhat.com ([209.132.183.28]:36926 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932159AbdCJSTB (ORCPT ); Fri, 10 Mar 2017 13:19:01 -0500 Date: Fri, 10 Mar 2017 12:18:58 -0600 From: Josh Poimboeuf To: Paul Menzel Cc: Steven Rostedt , Ingo Molnar , linux-kernel@vger.kernel.org Subject: Re: Kernel panic on Lenovo X60 with tracing enabled Message-ID: <20170310181858.xh46uslrdkvmxej5@treble> References: <20170309093630.69d02d7e@gandalf.local.home> <20170309161602.blwj36l6ckg3yh5g@treble> <20170309112936.7e220f61@gandalf.local.home> <2b0704a6a3cd8a97890340c7fa0133a9@molgen.mpg.de> <20170309230412.vpijtp3u5atbs7c7@treble> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.6.0.1 (2016-04-01) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Fri, 10 Mar 2017 18:19:01 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 10, 2017 at 09:53:29AM +0100, Paul Menzel wrote: > Dear Josh, > > > On 03/10/17 00:04, Josh Poimboeuf wrote: > > On Thu, Mar 09, 2017 at 09:43:47PM +0100, Paul Menzel wrote: > > > On 2017-03-09 17:29, Steven Rostedt wrote: > > > > On Thu, 9 Mar 2017 10:16:02 -0600 Josh Poimboeuf wrote: > > > > > > > > > On Thu, Mar 09, 2017 at 09:36:30AM -0500, Steven Rostedt wrote: > > > > > > On Thu, 9 Mar 2017 13:12:28 +0100 Paul Menzel wrote: > > > > > > > > > > Hopefully, I am contacting the right people for my issue. > > > > > > > > > > > > > > Suspending a system with Linux 4.9.13 with tracing enabled, it fails > > > > > > > with the screen still enabled, and the LED blinking. Attaching a serial > > > > > > > console to the dock, shows the messages below. > > > > > > > > > > > > I'm betting this is a compiler bug, as that bug that printed is the > > > > > > internal ftrace check for it. (note the bug is only in x86-32 not > > > > > > x86-64) > > > > > > > > > > > > Funny, we are just talking about this bug in another thread, but with a > > > > > > different symptom. > > > > > > > > > > > > Josh, did you say this goes away if you disable optimize for size or > > > > > > does it need to be enabled? > > > > > > > > > > Yeah, assuming it's the same problem, then this is caused by > > > > > CONFIG_CC_OPTIMIZE_FOR_SIZE. It would be fixed by changing it to > > > > > CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE. > > > > > > > > Paul, do you have CONFIG_CC_OPTIMIZE_FOR_SIZE enabled? Can you set it > > > > to PERFORMANCE and see if the problem goes away? > > > > > > As far as I can see, the Debian Linux kernel is built with > > > `CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE=y`. > > > > > > So it might be a different problem? > > > > Is it a stock Debian kernel? If so, do you have a link where it can be > > downloaded? > > Sure, hopefully [3] works for you. > > ``` > dpkg -x linux-image-4.9.0-0.bpo.2-686-pae-unsigned_4.9.13-1~bpo8+1_i386.deb > target-directory Thanks, that helped. One of the functions on the stack trace has the buggy prologue: acpi_pm_device_sleep_wake: c138048c: 57 push %edi c138048d: 8d 7c 24 08 lea 0x8(%esp),%edi c1380491: 83 e4 f8 and $0xfffffff8,%esp c1380494: ff 77 fc pushl -0x4(%edi) c1380497: 55 push %ebp c1380498: 89 e5 mov %esp,%ebp c138049a: 57 push %edi c138049b: 56 push %esi c138049c: 53 push %ebx c138049d: 83 ec 0c sub $0xc,%esp c13804a0: e8 e7 bf 21 00 call 0xc159c48c (mcount) And the config file indeed has CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE=y. I found the root cause after a little digging. drivers/acpi/Makefile is setting '-Os' manually: ccflags-y := -Os That line predates git history, so I don't know why it's there, but I'd guess we can probably remove it. I'll submit a fix for it along with the other -maccumulate-outoing-args related patch I was going to do. -- Josh