From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753286Ab2DCJum (ORCPT ); Tue, 3 Apr 2012 05:50:42 -0400 Received: from e28smtp01.in.ibm.com ([122.248.162.1]:43118 "EHLO e28smtp01.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751394Ab2DCJul (ORCPT ); Tue, 3 Apr 2012 05:50:41 -0400 Message-ID: <4F7AC7DF.3050905@linux.vnet.ibm.com> Date: Tue, 03 Apr 2012 15:20:23 +0530 From: "Srivatsa S. Bhat" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:11.0) Gecko/20120329 Thunderbird/11.0.1 MIME-Version: 1.0 To: Martin Steigerwald CC: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, a.p.zijlstra@chello.nl, stern@rowland.harvard.edu, rjw@sisk.pl, pavel@ucw.cz Subject: Re: [REGRESSION] NMI received for unknown reason 3c on CPU 0, strange powersaving mode? References: <201203301304.49708.Martin@lichtvoll.de> <4F7987D0.3090106@linux.vnet.ibm.com> (sfid-20120402_143911_704229_5D7541F7) <201204030950.02778.Martin@lichtvoll.de> In-Reply-To: <201204030950.02778.Martin@lichtvoll.de> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit x-cbid: 12040309-4790-0000-0000-0000020E1F73 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/03/2012 01:20 PM, Martin Steigerwald wrote: > Am Montag, 2. April 2012 schrieb Srivatsa S. Bhat: >> On 03/30/2012 04:34 PM, Martin Steigerwald wrote: >>> Hi! >>> >>> Since some time I am seeing things like >>> >>> Message from syslogd@merkaba at Mar 30 00:29:30 ... >>> >>> kernel:[49074.294260] Uhhuh. NMI received for unknown reason 3c on >>> CPU 0. >>> >>> Message from syslogd@merkaba at Mar 30 00:29:30 ... >>> >>> kernel:[49074.294263] Do you have a strange power saving mode >>> enabled? >>> >>> Message from syslogd@merkaba at Mar 30 00:29:30 ... >>> >>> kernel:[49074.294264] Dazed and confused, but trying to continue >>> >>> on resume after in-kernel hibernation. >> >> Do you see this after suspend-to-ram too? >> >>> I do not see any trace of it in syslog, kern.log or dmesg. >>> >>> From the timestemp it seems that these messages are issued shortly >>> before I send the laptop to hibernation last night. >>> >>> >>> I am using a ThinkPad T520 with Intel(R) Core(TM) i5-2520M CPU @ >>> 2.50GHz and Sandybridge graphics. >>> >>> I am not exactly sure since when it happens, cause I basically >>> ignored it for quite some time. Might be some 3.2 kernel where it >>> started, maybe even the first 3.2 kernel I had. Currently I am >>> using: >>> >>> martin@merkaba:~> cat /proc/version >>> Linux version 3.3.0-trunk-amd64 (Debian 3.3-1~experimental.1) >>> (debian- kernel@lists.debian.org) (gcc version 4.6.3 (Debian >>> 4.6.3-1) ) #1 SMP Thu Mar 22 18:02:10 UTC 2012 >>> >>> Since I am quite sure I didn´t see this with the first kernel I used >>> on this machine, which was a 2.6.39 if I remember correctly, I >>> consider this to be a regression for now. >>> >>> >>> I did not see any other strange effects, only this message. >>> >>> >>> When searching for it I see quite some references¹. But what I looked >>> at seemed to either quite old or different in that the machine was >>> frozen then. >> >> There was once such a bug report and commit 144060fee (perf: Add PM >> notifiers to fix CPU hotplug races) tried to fix it, however it didn't >> work out IIRC. >> >> Can you please try out the pm-test framework and let us know in which >> phase this message is encountered? >> Documentation/power/basic-pm-debugging.txt >> >> 1. Recompile the kernel with CONFIG_PM_DEBUG=y >> 2. # cat /sys/power/pm_test >> 3. # echo > /sys/power/pm_test >> Use the values from the list given in step 2. >> From freezer to core, it is increasing depth of suspend phase. >> 4. # echo mem > /sys/power/state (for suspend-to-ram) >> or echo disk > /sys/power/state (for suspend-to-disk) >> >> It would be great if you could tell which of the phases (freezer to >> core) fails. > > Here I have the one from this morning. This time as resume time: > > martin@merkaba:~> > Message from syslogd@merkaba at Apr 3 09:10:15 ... > kernel:[ 3755.145282] Uhhuh. NMI received for unknown reason 3c on CPU 0. > > Message from syslogd@merkaba at Apr 3 09:10:15 ... > kernel:[ 3755.145285] Do you have a strange power saving mode enabled? > > Message from syslogd@merkaba at Apr 3 09:10:15 ... > kernel:[ 3755.145286] Dazed and confused, but trying to continue > > > And here are the tests - short summary I was not able to reproduce the > issue - nothing means that there was no furch NMI message on the Konsole > window where it usually appears: > > merkaba:~> cat /sys/power/pm_test > [none] core processors platform devices freezer > merkaba:~> echo "core" > /sys/power/pm_test > merkaba:~> echo "mem" > /sys/power/state > merkaba:~> echo nothing > nothing > merkaba:~> echo "disk" > /sys/power/state > merkaba:~> echo nothing > nothing > merkaba:~> echo "processors" > /sys/power/pm_test > merkaba:~> echo "mem" > /sys/power/state > merkaba:~> echo nothing > nothing > merkaba:~> cat /sys/power/pm_test > none core [processors] platform devices freezer > merkaba:~> echo "disk" > /sys/power/state > merkaba:~> echo nothing > nothing > merkaba:~> echo "platform" > /sys/power/pm_test > merkaba:~> echo "mem" > /sys/power/state > merkaba:~> echo nothing > nothing > merkaba:~> echo "disk" > /sys/power/state > merkaba:~> echo nothing > nothing > merkaba:~> echo "devices" > /sys/power/pm_test > merkaba:~> echo "mem" > /sys/power/state > merkaba:~> echo nothing > nothing > merkaba:~> echo "disk" > /sys/power/state > merkaba:~> echo nothing > nothing > merkaba:~> echo "freezer" > /sys/power/pm_test > merkaba:~> echo "mem" > /sys/power/state > merkaba:~> echo nothing > nothing > merkaba:~> echo "disk" > /sys/power/state > merkaba:~> echo nothing > nothing > > > Now trying a regular hibernation: > > merkaba:~> echo "none" > /sys/power/pm_test > merkaba:~> cat /sys/power/pm_test > [none] core processors platform devices freezer > > > Nothing. > > > Now trying a regular hibernation with some minutes downtime and > unplugging the power from the laptop. > > > Nothing as well. > > > Now I am puzzled. > > > Maybe its the switch from minidock to no dock and vice versa? > Oh.. so you couldn't reproduce the problem.. Can you try with the original setup (minidock?) with which you found the issue during hibernation and see what pm_test has to say in that case? Regards, Srivatsa S. Bhat