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Date: Wed, 18 Oct 2006 09:28:58 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Daniel Walker <dwalker@mvista.com>
Subject: Re: [PATCH -rt] powerpc update
Message-ID: <20061018072858.GA29576@elte.hu>
References: <20061003155358.756788000@dwalker1.mvista.com>
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* Daniel Walker <dwalker@mvista.com> wrote:

> Pay close attention to the fasteoi interrupt threading. I added usage 
> of mask/unmask instead of using level handling, which worked well on 
> PPC.

this is wrong - it should be doing mask+ack.

also note that you changed:

> -		goto out_unlock;

to:

> +		goto out;

and you even tried to hide your tracks:

>  out:
>  	desc->chip->eoi(irq);
> -out_unlock:
>  	spin_unlock(&desc->lock);

:-)

really, the ->eoi() op should only be called for true fasteoi cases. 
What we want here is to turn the fasteoi handler into a handler that 
does mask+ack and then unmask. Not 'mask+eoi ... unmask' as your patch 
does.

	Ingo