From mboxrd@z Thu Jan  1 00:00:00 1970
From: Min Lee <min.lee@gatech.edu>
Subject: [Q] guest and user protection on x86-64 by paging
Date: Sun, 01 Aug 2010 12:01:14 -0400
Message-ID: <4C559A4A.1030809@gatech.edu>
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Hi, folks.
one question. I'll read source code, but if one can give me brief overview, 
it would be so helpful. On x86-64, guest and user runs both in ring 3, and 
protect from each other by paging mechanism. but, how? Then page table 
should be modified and TLB would be flushed for every system call. This 
would be some overhead, I think. Is this what Xen is doing? If not, how 
paging mechanism protect guest from its application?
Thanks
Min