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Subject: Re: [Qemu-devel] page fault during ins
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Date: Thu, 23 Dec 2004 09:45:41 +0100
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To: Piotras <piotras@gmail.com>, qemu-devel@nongnu.org

On Wed, 2004-12-15 at 09:17 +0100, Piotras wrote:
> Do we have any device where iomem read changes device state? 
> Wouldn't such hardware cause problems with speculative execution 
> (memory reads) on some real CPUs? Or am I missing something?

This is still quit common unfortunately...

On archs like ppc, this is why IO space is marked "Guarded" to prevent
speculation.

Ben.