Date: Thu, 27 Nov 2008 02:01:01 +0100
From: Bastian Blank <bastian@waldi.eu.org>
To: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: oleg@redhat.com, ebiederm@xmission.com, roland@redhat.com,
       containers@lists.osdl.org, linux-kernel@vger.kernel.org,
       xemul@openvz.org
Subject: Re: [RFC][PATCH 3/5] Determine if sender is from ancestor ns
Message-ID: <20081127010101.GA13545@wavehammer.waldi.eu.org>
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	Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>, oleg@redhat.com,
	ebiederm@xmission.com, roland@redhat.com, containers@lists.osdl.org,
	linux-kernel@vger.kernel.org, xemul@openvz.org
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On Tue, Nov 25, 2008 at 07:46:11PM -0800, Sukadev Bhattiprolu wrote:
> +#ifdef CONFIG_PID_NS
> +#define SIG_FROM_USER  INT_MIN         /* MSB */

Is it really a wise idea to mix this into the signal number? Also this
definition looks odd. If you want the highest bit, you should mention
this explicitely with 1U<<31.

If I see this correctly this information is already covered in si_code
with SI_USER and SI_TKILL. SI_KERNEL is used for explicit kernel
generated signals.

> +static inline int siginfo_from_ancestor_ns(struct task_struct *t,
> +			siginfo_t *info)
> +{
> +	if (!is_si_special(info) && (info->si_signo & SIG_FROM_USER)) {
> +		/* if t can't see us we are from parent ns */

What?

>  static int send_signal(int sig, struct siginfo *info, struct task_struct *t,
>  			int group)
>  {
>  	struct sigpending *pending;
>  	struct sigqueue *q;
> +	int from_ancestor_ns;
>  
>  	trace_sched_signal_send(sig, t);
>  
> +	from_ancestor_ns = siginfo_from_ancestor_ns(t, info);
> +

This is not used at all here?

Bastian

-- 
Those who hate and fight must stop themselves -- otherwise it is not stopped.
		-- Spock, "Day of the Dove", stardate unknown
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