Messages in this thread | | | Date | Fri, 3 Jan 1997 18:01:56 -0700 (MST) | From | Derrik Pates <> | Subject | RE: pentium 4MB pages question for you MMU hackers |
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On Fri, 3 Jan 1997, Michael Nelson wrote:
> >The Intel CPUs (and most other CPUs that do multitasking) have what are > >called "rings" which describe what kind of access the process can get to > >the CPU. The lowest ringlevel (ring 0) is your kernel and driver code. > >Most other CPUs only have 2 ringlevels, but Intel 32-bit CPUs (the 386 and > >up) have 4 ringlevels, but no one has ever put anything but rings 0 and 3 > >to use. > > That's not true at all, there are several operating systems that have put the other rings to use. QNX and OS/2 to name a couple. > > -mike >
Ahhh... Well, at least someone has put that feature to use. As far as I had read tho, it hadn't been used. I guess I stand corrected.
Derrik Pates dpates@cavern.nmsu.edu
"What'll you two lovable plush toys have?" "How 'bout a root beer popsicle and an Orange Julius? What about you, Max?" "Dishwater! And put it in a dirty glass!" -Sam & Max "Fair Wind to Java"
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