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Date: Tue, 7 Jul 2015 11:29:21 +0100
From: Will Deacon <will.deacon@arm.com>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Subject: Re: [Ksummit-discuss] [TECH TOPIC] Semantics of MMIO mapping
 attributes accross archs
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On Tue, Jul 07, 2015 at 10:56:15AM +0100, Will Deacon wrote:
> As long as the accessors are required to enforce ordering that the
> underlying memory type is incapable of providing, I don't see what we
> could do to solve this (somehow make readX/writeX behaviour dependent on
> the pointer?).

... which we could do using pointer tags, but christ is that going to be
confusing to use (casting an io-relaxed pointer to order against DMA!).

Will