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Date: Thu, 10 Nov 2011 09:30:09 -0800
From: Tejun Heo <tj@kernel.org>
To: Pavel Emelyanov <xemul@parallels.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
        Cyrill Gorcunov <gorcunov@openvz.org>,
        Glauber Costa <glommer@parallels.com>, Nathan Lynch <ntl@pobox.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Oleg Nesterov <oleg@redhat.com>, Serge Hallyn <serue@us.ibm.com>,
        Daniel Lezcano <dlezcano@fr.ibm.com>
Subject: Re: [PATCH 3/3] pids: Make it possible to clone tasks with given
 pids
Message-ID: <20111110173009.GH27258@google.com>
References: <4EBC0696.9030103@parallels.com>
 <4EBC06DB.3090202@parallels.com>
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Hello, Pavel.

>  	for (i = ns->level; i >= 0; i--) {
> -		nr = alloc_pidmap(tmp);
> +		nr = 0;
> +		if (unlikely(want_pids != NULL)) {
> +			if (get_user(nr, want_pids)) {
> +				nr = -EFAULT;
> +				goto out_free;
> +			}
> +
> +			if (nr != 0) {
> +				want_pids++;
> +				nr = set_pidmap(tmp, nr);
> +			} else
> +				want_pids = NULL; /* optimize above */
> +		}
> +		if (nr == 0)
> +			nr = alloc_pidmap(tmp);

Hmmm... is it necessary to be able to replicate pids on all
namespaces?  Also, isn't it a bit weird to be able to request PIDs in
the namespaces which is beyond the task which requested cloning?

Thanks.

-- 
tejun