[Mono-list] Announcement: New application-level x86 virtual machine

[Bryan Ford]

Hi folks, I hope this announcement might be of interest to some of you as 
being related to and in some respects complementary to Mono and other 
application-level virtual machines. 
 
I've just released the first (very experimental) version of VX32, a new 
x86-based application-level virtual environment. Unlike most x86-based virtual 
machines such as QEMU and plex86, VX32 is more comparable in 
function to Kaffe or Mono: VX32 only implements the user-mode portion of the 
x86 architecture rather than emulating a whole machine including devices, and 
is intended for use by applications to create lightweight, highly 
controllable execution environments for safe application plug-ins and the 
like, rather than for running whole operating systems. VX32 might be 
especially appropriate for safely running Unix filter-like applications such 
as compressors, decompressors, crypto software, or transcoders, where the 
legacy code bases you often want to re-use are already written in C or other 
non-typesafe languages.  VX32 could also potentially provide the basis for a 
"safe native method" extension facility for typesafe languages such as Java 
and C#, if there is interest.
 
VX32 uses dynamic code rewriting techniques to sandbox guest code efficiently 
on x86 host processors, typically costing less than 15% slowdown versus 
native x86-32 execution. I'm also working on instruction set emulation and 
binary translation to make the environment portable to other host 
architectures.
 
The VX32 home page, including the first source release, is here: 
 
http://pdos.csail.mit.edu/~baford/vm/ 
 
The home page for VXA (Virtual eXecutable Archives), a related project that 
uses VX32 to turn ZIP files into "active archvies", is here: 
 
http://pdos.csail.mit.edu/~baford/vxa/ 
 
Finally, a paper that discusses both VX32 and VXA can be found here: 
 
http://www.brynosaurus.com/pub/os/vxa.pdf 
 
I would appreciate any comments and feedback. Thanks for your time!
 
Bryan