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	Mon, 13 Jul 2009 16:18:41 -0400
Subject: Re: iwl: potential deadlock?
From: reinette chatre <reinette.chatre@intel.com>
To: Jiri Slaby <jirislaby@gmail.com>
Cc: "Zhu, Yi" <yi.zhu@intel.com>,
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Date: Mon, 13 Jul 2009 13:18:40 -0700
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Hi Jiri,

On Mon, 2009-07-13 at 12:34 -0700, Jiri Slaby wrote:
> Hi,
> 
> we found a potential deadlock in iwl code by our tool.

What tool is this?

> 
> Can this happen:

I don't think so ...

> iwl_update_tkip_key()
> -> spin_lock_irqsave(&priv->sta_lock)
> -> iwl_send_add_sta()

iwl_send_add_sta() is called here with flags = CMD_ASYNC

In iwl_send_add_sta() we have:
	if (ret || (flags & CMD_ASYNC))
		return ret;

>    -> iwl_sta_ucode_activate()

... so this is not run in this case.

>       -> spin_lock_irqsave(&priv->sta_lock)

Reinette