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 S1754512AbdCFVZ0 (ORCPT <rfc822;w@1wt.eu>);
        Mon, 6 Mar 2017 16:25:26 -0500
Received: from mail-yw0-f193.google.com ([209.85.161.193]:35786 "EHLO
        mail-yw0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1754288AbdCFVZU (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Mon, 6 Mar 2017 16:25:20 -0500
Date: Mon, 6 Mar 2017 15:56:12 -0500
From: Tejun Heo <tj@kernel.org>
To: Tahsin Erdogan <tahsin@google.com>
Cc: Christoph Lameter <cl@linux.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Chris Wilson <chris@chris-wilson.co.uk>,
        Andrey Ryabinin <aryabinin@virtuozzo.com>,
        Roman Pen <r.peniaev@gmail.com>,
        Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
        Michal Hocko <mhocko@suse.com>, zijun_hu <zijun_hu@htc.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/3] percpu: acquire pcpu_lock when updating
 pcpu_nr_empty_pop_pages
Message-ID: <20170306205612.GF26127@htj.duckdns.org>
References: <20170225210019.23610-1-tahsin@google.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20170225210019.23610-1-tahsin@google.com>
User-Agent: Mutt/1.7.1 (2016-10-04)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Sat, Feb 25, 2017 at 01:00:19PM -0800, Tahsin Erdogan wrote:
> Update to pcpu_nr_empty_pop_pages in pcpu_alloc() is currently done
> without holding pcpu_lock. This can lead to bad updates to the variable.
> Add missing lock calls.
> 
> Fixes: b539b87fed37 ("percpu: implmeent pcpu_nr_empty_pop_pages and chunk->nr_populated")
> Signed-off-by: Tahsin Erdogan <tahsin@google.com>

Applied to percpu/for-4.11-fixes w/ stable cc'd.

Thanks.

-- 
tejun