Capbility Concepts

[Gernot Heiser]

>>>>> "NH" == Norman Hardy <norm@netcom.com> writes:

NH> Yes. I was addressing those capability systems where the holder of a
NH> capability could not see the bits.  The System 38 is like this. Seeing as
NH> how the capabilities are among the data, it hardly seems either
NH> partitioned or segregated.

Are you sure? I don't have the S/38 papers handy (working from home
today) but I seem to remember that it was actually possible for
unprivileged code to copy a cap, but the hardware would turn of the
capability bit then, converting it to simple data.

Gernot
--
Gernot Heiser                ,--_|\   School of Computer Sci. & Engin.
Phone:  +61 2 9385 5156     /      \  The University of NSW
Fax:    +61 2 9385 5533     \_,--._*  UNSW SYDNEY NSW 2052, Australia
E-mail: gernot@unsw.edu.au        v   http://www.cse.unsw.edu.au/~gernot
PGP fingerprint: 94 1E B8 28 25 FD 7C 94  20 10 92 E5 0B FF 39 8F