From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <nfont@linux.vnet.ibm.com>
Received: from e28smtp04.in.ibm.com (e28smtp04.in.ibm.com [122.248.162.4])
 (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits))
 (Client CN "e28smtp04.in.ibm.com", Issuer "GeoTrust SSL CA" (not verified))
 by ozlabs.org (Postfix) with ESMTPS id 1A9F42C0084
 for <linuxppc-dev@lists.ozlabs.org>; Tue, 25 Jun 2013 12:47:21 +1000 (EST)
Received: from /spool/local
 by e28smtp04.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only!
 Violators will be prosecuted
 for <linuxppc-dev@lists.ozlabs.org> from <nfont@linux.vnet.ibm.com>;
 Tue, 25 Jun 2013 08:11:06 +0530
Received: from d28relay03.in.ibm.com (d28relay03.in.ibm.com [9.184.220.60])
 by d28dlp02.in.ibm.com (Postfix) with ESMTP id 94E30394004E
 for <linuxppc-dev@lists.ozlabs.org>; Tue, 25 Jun 2013 08:17:17 +0530 (IST)
Received: from d28av01.in.ibm.com (d28av01.in.ibm.com [9.184.220.63])
 by d28relay03.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id
 r5P2lWwH31523028
 for <linuxppc-dev@lists.ozlabs.org>; Tue, 25 Jun 2013 08:17:32 +0530
Received: from d28av01.in.ibm.com (loopback [127.0.0.1])
 by d28av01.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id
 r5P2lHU1006139
 for <linuxppc-dev@lists.ozlabs.org>; Tue, 25 Jun 2013 02:47:17 GMT
Message-ID: <51C904B3.4060509@linux.vnet.ibm.com>
Date: Mon, 24 Jun 2013 21:47:15 -0500
From: Nathan Fontenot <nfont@linux.vnet.ibm.com>
MIME-Version: 1.0
To: Michael Ellerman <michael@ellerman.id.au>
Subject: Re: [PATCH] Do not update sysfs cpu registration from invalid context
References: <51C8543F.6080905@linux.vnet.ibm.com>
 <20130625015057.GC14051@concordia>
In-Reply-To: <20130625015057.GC14051@concordia>
Content-Type: text/plain; charset=ISO-8859-1
Cc: linuxppc-dev@lists.ozlabs.org
List-Id: Linux on PowerPC Developers Mail List <linuxppc-dev.lists.ozlabs.org>
List-Unsubscribe: <https://lists.ozlabs.org/options/linuxppc-dev>,
 <mailto:linuxppc-dev-request@lists.ozlabs.org?subject=unsubscribe>
List-Archive: <http://lists.ozlabs.org/pipermail/linuxppc-dev/>
List-Post: <mailto:linuxppc-dev@lists.ozlabs.org>
List-Help: <mailto:linuxppc-dev-request@lists.ozlabs.org?subject=help>
List-Subscribe: <https://lists.ozlabs.org/listinfo/linuxppc-dev>,
 <mailto:linuxppc-dev-request@lists.ozlabs.org?subject=subscribe>

On 06/24/2013 08:50 PM, Michael Ellerman wrote:
> On Mon, Jun 24, 2013 at 09:14:23AM -0500, Nathan Fontenot wrote:
>> The topology update code that updates the cpu node registration in sysfs
>> should not be called while in stop_machine(). The register/unregister
>> calls take a lock and may sleep.
>>
>> This patch moves these calls outside of the call to stop_machine().
> 
> What happens? Do we lockup or do you just get a warning?
> 
> And what commit introduced the breakage?

Guilty on on all counts. Hopefully I can still get by with stern warning.

-Nathan