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Date: Mon, 30 Jan 2012 14:46:01 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: Arve =?iso-8859-1?B?SGr4bm5lduVn?= <arve@android.com>,
        KOSAKI Motohiro <kosaki.motohiro@gmail.com>,
        Greg Kroah-Hartman <gregkh@suse.de>, San Mehat <san@google.com>,
        Colin Cross <ccross@android.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        linux-kernel@vger.kernel.org, kernel-team@android.com,
        linaro-kernel@lists.linaro.org
Subject: Re: [PATCH 3/3] staging: android: lowmemorykiller: Drop
	tasklist_lock usage
Message-ID: <20120130134601.GB14110@redhat.com>
References: <20120130011348.GC30274@oksana.dev.rtsoft.ru>
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On 01/30, Anton Vorontsov wrote:
>
> @@ -132,8 +134,8 @@ static int lowmem_shrink(struct shrinker *s, struct shrink_control *sc)
>  	}
>  	selected_oom_adj = min_adj;
>
> -	read_lock(&tasklist_lock);
> -	for_each_process(p) {
> +	for_each_tgid(ns, iter) {

This makes force_sig() below unsafe, it can race with the exiting task.

Oleg.