From mboxrd@z Thu Jan  1 00:00:00 1970
From: linux@arm.linux.org.uk (Russell King - ARM Linux)
Date: Thu, 15 Jul 2010 10:59:28 +0100
Subject: Problem with dma_alloc_coherent at linux-2.6.33-arm1 , with
	RealView platform,board PBX-A9 and armv7 instructions.
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On Thu, Jul 15, 2010 at 05:56:41PM +0800, David Yang wrote:
> I have explicitly added the barrier() in my driver, but it did't work.

This imples that you've tried your own solution, which is completely
different from Catalin's patches.

barrier() is just a compiler barrier, nothing more.  It won't have any
effect on external memory ordering.  It's not surprising this doesn't
have much effect.