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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] [PATCH] [RFC] cleanup cpu-exec.c:
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Date: Thu, 30 Apr 2009 18:07:35 +0100
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To: qemu-devel@nongnu.org
Cc: Avi Kivity <avi@redhat.com>, Nathan Froyd <froydnj@codesourcery.com>

On Thursday 30 April 2009, Avi Kivity wrote:
> Paul Brook wrote:
> > This is most likely a remnant of the long-deceased qemu-fast, which used
> > mmap tricks to avoid MMU emulation in system mode.
>
> I'd really like to see kvm used to implement something like this (to
> emulate non-x86 on x86).

It's something I've considered a few times. It gets hairy fairly quickly 
though. You're probably also going to hit a world of pain if your host 
pagesize is larger than your guest pagesize, and for guests with a software 
managed TLB shadow paging gets much more interesting.

There's very little of the old code left, and it's bitrotten enough that 
there's no point trying to keep it on the offchance that it'll be useful.

Paul