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Date: Mon, 19 May 2008 16:51:22 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Matthias Kaehlcke <matthias@kaehlcke.net>
Cc: ecashin@coraid.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ATA over Ethernet: Convert emsgs_sema in a completion
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On Fri, 16 May 2008 21:11:33 +0200
Matthias Kaehlcke <matthias@kaehlcke.net> wrote:

> @@ -216,7 +217,7 @@ aoechr_read(struct file *filp, char __user *buf, size_t cnt, loff_t *off)
>  
>  		spin_unlock_irqrestore(&emsgs_lock, flags);
>  
> -		n = down_interruptible(&emsgs_sema);
> +		n = wait_for_completion_interruptible(&emsgs_comp);

Patch looks OK, but I worry about this code.  Suppose a signal is sent
and we return to userspace with the complete() still outstanding.  Then
someone removes the module.  

Perhaps there is synchronisation code which prevents that crash?