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Date: Tue, 18 Dec 2012 12:30:31 +0100
From: Hans de Goede <hdegoede@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 09/26] ehci: Use uframe precision for
 interrupt threshold checking
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To: Gerd Hoffmann <kraxel@redhat.com>
Cc: qemu-devel@nongnu.org

Hi,

On 12/18/2012 12:03 PM, Gerd Hoffmann wrote:
>    Hi,
>
>> Can qemu not handle an mmio range where writes are trapped, but reads are
>> not? That would force the use of the shadow variable, but should otherwise
>> provide a nice speedup.
>
> No.  vmexit is needed anyway btw, but the round-trip to qemu userspace
> could be short-cutted in theory.  It's non-trivial though.  Alex had a
> talk about it at kvm forum (covering ide).

Ok, then I'll respin the patch getting rid of the shadow variable.

Regards,

Hans