[vbox-dev] Memory tracing on Guest Page tables

Michael Thayer michael.thayer at oracle.com
Thu Aug 25 01:26:22 PDT 2011

Hello Francesco,

On Mon, 2011-08-22 at 18:25 +0200, Francesco Di Paolo wrote:
> i've already posted a similar question some months ago...but nobody
> gave me an answer. So i'm trying again. It's just a yes or no
> question:in order to maintain  consistency between shadow PT and guest
> PT, we have to write-protect the guest PTs(the memory tracing
> technique). Is it right that,in order to protect them, we set the
> Write Protection bit of CR0 in the guest OS?
This is not my specialty, but no, we don't do any manipulation of the
guest OS CPU of that sort, as that CPU is merely something emulated by
us (using the host CPU directly as much as possible of course, but
emulated nonetheless).  WP must be set in CR0 on the host CPU of course.


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