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From: Robert Finch <robfi680@gmail.com>
Newsgroups: comp.arch
Subject: Re: Capabilities, Anybody?
Date: Wed, 13 Mar 2024 18:43:59 -0400
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> 
> In the past, capability machines wanted to use capabilities for all 
> relocation and all protection. As long as this is the case, an applica-
> tion has an unbounded need for capabilities.

It seems like it would have a lot of overhead, but it might be worth it 
for security.
> 
> You can grant this with limited capabilities (top 4-odd bits) only when
> you have a means to load a new capability into a known <capability> base
> register[i]. Since this is privileged data, either the specified function-
> ality of this instruction is precisely specified and operates with 
> access to GuestOS address space.....it is difficult to imagine how to 
> add Hyper-
> Vision on top of GuestOS supervision.
> {{Or do you intend to void Hypervisors?}}

I got the impression that with capabilities processor modes may not be 
necessary. I think the distinction between hypervisor / supervisor may 
be lost. Not sure that is a good idea.

om=MSDN