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From: Pavel Fedin <p.fedin@samsung.com>
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Date: Wed, 25 Nov 2015 10:00:40 +0300
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Subject: Re: [Qemu-devel] [PATCH] vfio: Align iova also to IOMMU page size
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To: 'Peter Maydell' <peter.maydell@linaro.org>, 'Alex Williamson' <alex.williamson@redhat.com>
Cc: 'QEMU Developers' <qemu-devel@nongnu.org>

 Hello!

> There are a number of different interesting page sizes here:
>  * the host kernel page size
>  * the target CPU architecture's worst-case smallest page size
>  * the page size the guest kernel is actually using at the moment
>    (consider a 4K-page guest kernel on a 64K-page host kernel)
> 
> These don't necessarily have to all be the same. I would
> expect VFIO to be interested in the host kernel page size,
> not TARGET_PAGE_ALIGN.

 So would the appropriate fix be just replacing TARGET_PAGE_ALIGN with HOST_PAGE_ALIGN?
 Alex: there's however, still no answer to "why are we aligning up, not down?" question..

Kind regards,
Pavel Fedin
Expert Engineer
Samsung Electronics Research center Russia