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From: Robert Finch <robfi680@gmail.com>
Newsgroups: comp.arch
Subject: Re: Capabilities, Anybody?
Date: Sun, 17 Mar 2024 19:41:15 -0400
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Busily working away on adding capabilities to the current project, and 
decided to add the operating mode / privilege ring (two bits) to the 
capabilities instead of 'permit access system registers' (one bit).

I think this makes it possible for capabilities to work outside of the 
current operating mode. The 'permit access system registers' was within 
the current operating mode. Adding the operating mode makes the 
capability mode agnostic.

However, I am unsure of the access implications. One could then give a 
capability with the highest privilege mode to a user app.

I was going to try and eliminate the operating mode concept from the 
current project and rely on capabilities instead. But there are 
different levels of instructions and registers that could be allowed in 
a capability. Using the operating mode acts as an indirect means to 
specify these.