From: ao950 AT FreeNet DOT Carleton DOT CA (Paul Derbyshire)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Ring 0?
Date: 9 Mar 1997 04:25:24 GMT
Organization: The National Capital FreeNet
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OK...why do they call it "ring" then? Does it refer to a ring like
circular data structure or something else?

Also, do ring 0 programs run faster? I guess because the CPU isn't always
second-guessing memory accesses to see if they violate segment bounds the
software has been assigned?

As for a ring 3 program being unable to currupt the kernel, I'm not sure
this is entirely correct. I discovered that a DOS program running in a DOS
box under Win 95 (and DOS boxes presumably run in ring 3) can crash the
machine with a bad memory write.

--
    .*.  Where feelings are concerned, answers are rarely simple [GeneDeWeese]
 -()  <  When I go to the theater, I always go straight to the "bag and mix"
    `*'  bulk candy section...because variety is the spice of life... [me]
Paul Derbyshire ao950 AT freenet DOT carleton DOT ca, http://chat.carleton.ca/~pderbysh