17 Jun
2018
17 Jun
'18
4:27 p.m.
Noel Chiappa <jnc(a)mercury.lcs.mit.edu> writes:
ISTR reading that it runs in Supervisor mode (no doubt
so it could use the
Supervisor mode virtual address space, and not have to go crazy with overlays
in the Kernet space).
Indeed. From "Installing and Operating 2.11BSD on the PDP-11":
The networking in 2.11BSD runs in supervisor mode, separate from
the mainstream kernel. There is room without overlaying to hold
both a SL/IP and ethernet driver. This is a major win, as it
allows the networking to maintain its mbufs in normal data
space, among other things.
-tih
--
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