Date: Thu, 5 Jun 2008 14:13:18 +0900
From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
To: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: containers@lists.osdl.org, LKML <linux-kernel@vger.kernel.org>,
       Li Zefan <lizf@cn.fujitsu.com>, Paul Menage <menage@google.com>
Subject: Re: [RFC][PATCH] introduce task cgroup (#task restrictioon for
 prevent fork bomb by cgroup)
Message-Id: <20080605141318.ee9ec8a6.kamezawa.hiroyu@jp.fujitsu.com>
In-Reply-To: <20080605132512.9C31.KOSAKI.MOTOHIRO@jp.fujitsu.com>
References: <20080605132512.9C31.KOSAKI.MOTOHIRO@jp.fujitsu.com>
Organization: Fujitsu
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 993
Lines: 36

On Thu, 05 Jun 2008 13:43:06 +0900
KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> wrote:
> +static int task_cgroup_max_tasks_write(struct cgroup *cgrp,
> +				       struct cftype *cftype,
> +				       s64 max_tasks)
> +{
> +	struct task_cgroup *taskcg;
> +
> +	if ((max_tasks > INT_MAX) ||
> +	    (max_tasks < INT_MIN))
> +		return -EINVAL;

should be (max_tasks > INT_MAX) || (max_tasks < -1)) ?

> +
> +	taskcg = task_cgroup_from_cgrp(cgrp);
> +
> +	spin_lock(&taskcg->lock);
> +	if (max_tasks < taskcg->nr_tasks)
> +		return -EBUSY;
> +	taskcg->max_tasks = max_tasks;
> +	spin_unlock(&taskcg->lock);
This will cause dead lock.

And it seems this doesn't handle "attach failure".

It will be helpful Documentation somewhere.

Thanks,
-Kame

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/