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Date: Wed, 02 May 2007 16:30:19 -0500
From: Scott Wood <scottwood@freescale.com>
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To: Kumar Gala <galak@kernel.crashing.org>
Subject: Re: [PATCH v2] gianfar: Add I/O barriers when touching buffer
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Kumar Gala wrote:
> Why doesn't marking the bdp pointer volatile resolve the issue in  
> gfar_clean_rx_ring() to ensure load ordering?

Because that only addresses compiler reordering (and does so in a rather 
clumsy way -- not all accesses need to be strongly ordered), not 
hardware reordering.

-Scott