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From: Roland Dreier <rdreier@cisco.com>
To: Arjan van de Ven <arjan@infradead.org>
Subject: Re: MMIO and gcc re-ordering issue
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 > either via sparse or some fancy lockdep like "device store" thing?
 > If we can't test for it and it doesn't show up on x86 ... it'll just be
 > an eterrnal chase.

Ben's point is that it will start showing up on x86 because newer
compilers are reordering things...

 - R.