On 2003.10.05 07:40 John Hebert wrote:
> Great Caesar's ghost! How the heck can you come to that conclusion?
> 
> I think I know. Did you misinterpret the following quote? Or maybe a news 
> report you read made the misinterpretation?
> 
> "With assistance from Microsoft Research, we have a port of Windows XP to 
> Xen nearly complete, and are planning a FreeBSD 4.8 port in the near future 
> (volunteers welcome!)."
> 
> My interpretation is that Microsoft Research is helping with the WinXP port 
> only. The above quote is from Google's cache of 
> www.cl.cam.ac.uk/Research/SRG/netos/xen/, since the original site is down 
> at the moment.
> 

How I got there was the performance page which stated:

" Operating systems running over Xen execute in x86 privilege ring 1 instead of 
ring 0, which we reserve for Xen. This prevents guest OSes from using the 
normal privileged instructions to turn on/off interrupts, change page table 
bases etc. Instead, they must make a 'hypercall' down into Xen to ask the 
operation to be performed on their behalf. "

This is how DRM must work.  By using XEN or a XEN derivative for firmware, the 
owner of a machine can be put into "ring 1".  This enables the firmaware to 
block a copy of a "protected" chunk of memory.  Microsoft could use a 
derivative to of XEN as their next generation BIOS and make sure nothing but 
"signed" code runs and that no flaged file is every coppied.  

So, does that make any more sense?  Sure, I love the concept of Xen and can see 
many good uses for it.  That does not keep me from worrying that the makers of 
XP, the Xbox and other horror storries won't abuse it.  Microsoft has announced 
their intentions to "integrate" windoze with Phonenix BIOS.  XEN could be the 
next step.  

Reply via email to