From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1757829Ab1I3VlO (ORCPT <rfc822;w@1wt.eu>);
	Fri, 30 Sep 2011 17:41:14 -0400
Received: from oz.csail.mit.edu ([128.30.30.239]:52118 "EHLO
	ozymandias.localdomain" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org
	with ESMTP id S1755530Ab1I3VlH (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Fri, 30 Sep 2011 17:41:07 -0400
MIME-Version: 1.0
Content-Type: text/plain;
 charset=UTF-8;
 format=flowed
Content-Transfer-Encoding: 8bit
Date: Fri, 30 Sep 2011 17:40:33 -0400
From: Eric B Munson <emunson@mgebm.net>
To: Michel Lespinasse <walken@google.com>
Cc: <linux-mm@kvack.org>, <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
        Dave Hansen <dave@linux.vnet.ibm.com>, Rik van Riel <riel@redhat.com>,
        Balbir Singh <bsingharora@gmail.com>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Johannes Weiner <jweiner@redhat.com>,
        KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
        Hugh Dickins <hughd@google.com>, Michael Wolf <mjwolf@us.ibm.com>
Subject: Re: [PATCH 0/9] V2: idle page tracking / working set estimation
In-Reply-To: <CANN689EN8KsBZj_9cABjJoZNou_UegZ8uqB4Lx=uM-B_4aCd7A@mail.gmail.com>
References: <1317170947-17074-1-git-send-email-walken@google.com>
 <20110929164319.GA3509@mgebm.net>
 <CANN689H1G-USQYQrOTb47Hrc7KMjLdxkppYCDKsTUy5WhuRs7w@mail.gmail.com>
 <4186d5662b3fb21af1b45f8a335414d3@mgebm.net>
 <20110930181914.GA17817@mgebm.net>
 <CANN689EN8KsBZj_9cABjJoZNou_UegZ8uqB4Lx=uM-B_4aCd7A@mail.gmail.com>
Message-ID: <7bf74fcb33ce31bcc933db6d90b03733@mgebm.net>
User-Agent: Roundcube Webmail/0.5.1
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

 On Fri, 30 Sep 2011 14:16:25 -0700, Michel Lespinasse wrote:
> On Fri, Sep 30, 2011 at 11:19 AM, Eric B Munson <emunson@mgebm.net> 
> wrote:
>> I am able to recreate on a second desktop I have here (same model 
>> CPU but a
>> different MB so I am fairly sure it isn't dying hardware).  It looks 
>> to me like
>> a CPU softlocks and it stalls the process active there, so most 
>> recently that
>> was XOrg.  The machine lets me login via ssh for a few minutes, but 
>> things like
>> ps and cat or /proc files will start to work and give some output 
>> but hang.
>> I cannot call reboot, nor can I sync the fs and reboot via SysRq. 
>>  My next step
>> is to setup a netconsole to see if anything comes out in the syslog 
>> that I
>> cannot see.
>
> I haven't had time to try & reproduce locally yet (apologies - things
> have been coming up at me).
>
> But a prime suspect would be a bad interaction with
> CONFIG_MEMORY_HOTPLUG, as Kamezama remarked in his reply to patch 4. 
> I
> think this could be the most likely cause of what you're observing.

 I will try disabling Memory Hotplug on Monday and let you know if that 
 helps.

 Eric