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Subject: Re: [Qemu-devel] About qemu emulation speed (a
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Date: Wed, 14 Sep 2005 10:18:24 -0700
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To: qemu-devel@nongnu.org

On Wed, 2005-09-14 at 09:37 -0400, Jim C. Brown wrote:

> VMware handles kernel code. You are right that x86 code can't be 100% virtualized
> (even at the userland level) but VMware uses a lot of nasty disgusting tricks
> in order to work around them. (For example, playing with shadow pagetables
> so that a page of modified code is run but if the code tries to inspect itself
> it sees another (unexecuted) page that contains the original code.)
> 

Why disgusting?

Seems like a smart implementation given the options at hand.

Perhaps you meant disgusting because the Intel architecture forces a
virtualizer to handle a bunch of corner cases like this.

-- John.