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Date: Tue, 04 Jun 2013 21:11:16 +0200
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Subject: Re: [Qemu-devel] [PATCH v2 06/17] sysbus: add sysbus_pass_mmio
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To: Alex Williamson <alex.williamson@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>, qemu-devel@nongnu.org

Il 04/06/2013 19:47, Alex Williamson ha scritto:
> We'll see about that ;)

At the very least you broke the tie. :)

> It's true that it's simply a mental model of
> doing the required steps, then optimizing that makes vfio need a
> sprinkling of set ownership calls.  Paolo, your patch to move the
> PCI/VGA registration later solves this and completely hides memory
> region ownership from vfio.  That's great, but as Peter is arguing,
> leaves a hole that I'm not even aware that an owner is required for a
> memory region and the API still leaves me lots of opportunities to get
> it wrong.  So, I have to go back to Rusty's API design guidelines that
> an API should difficult to use incorrectly.  From what I see, I'm not
> sure we have that here.  An ugly compromise might be a runtime checks
> for orphan memory regions after a device is initialized, but that has
> it's own set of problems.  Thanks,

Then I'll hunt for the 800 owners.  In the meanwhile, patch
2/3/4/14/15/16/17 won't change from this series to the next, so a review
of those is welcome. :)

Paolo