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Subject: Re: [PATCH] pcxx: replace cli()/sti() with
	spin_lock_irqsave()/spin_unlock_irqrestore()
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: James Nelson <james4765@verizon.net>
Cc: kernel-janitors@lists.osdl.org,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, akpm@osdl.org
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Date: Mon, 20 Dec 2004 14:59:09 +0000
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On Gwe, 2004-12-17 at 22:34, James Nelson wrote:
> -	save_flags(flags);
> -	cli();
> +	spin_lock_irqsave(&pcxx_lock, flags);
>  	del_timer_sync(&pcxx_timer);

Not safe if the lock is grabbed by the timer between the lock and the
irqsave as it will spin on another cpu and the timer delete will never
finish.