Date: Sat, 16 Jun 2012 19:20:09 -0700 (PDT)
From: David Rientjes <rientjes@google.com>
To: Jiang Liu <jiang.liu@huawei.com>
cc: Mel Gorman <mgorman@suse.de>,
        KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
        KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Minchan Kim <minchan@kernel.org>, Hugh Dickins <hughd@google.com>,
        Keping Chen <chenkeping@huawei.com>, Tony Luck <tony.luck@intel.com>,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Xishi Qiu <qiuxishi@huawei.com>, Jiang Liu <liuj97@gmail.com>
Subject: Re: [PATCH] memory hotplug: fix invalid memory access caused by
 stale kswapd pointer
In-Reply-To: <1339645491-5656-1-git-send-email-jiang.liu@huawei.com>
Message-ID: <alpine.DEB.2.00.1206161919580.797@chino.kir.corp.google.com>
References: <1339645491-5656-1-git-send-email-jiang.liu@huawei.com>
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On Thu, 14 Jun 2012, Jiang Liu wrote:

> Function kswapd_stop() will be called to destroy the kswapd work thread
> when all memory of a NUMA node has been offlined. But kswapd_stop() only
> terminates the work thread without resetting NODE_DATA(nid)->kswapd to NULL.
> The stale pointer will prevent kswapd_run() from creating a new work thread
> when adding memory to the memory-less NUMA node again. Eventually the stale
> pointer may cause invalid memory access.
> 
> Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
> Signed-off-by: Jiang Liu <liuj97@gmail.com>

Acked-by: David Rientjes <rientjes@google.com>
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