On Sun, Jul 3, 2022 at 11:30 AM Bakul Shah <bakul@iitbombay.org> wrote:
You may be thinking of MINIX 1. It was a from-scratch implementation that was syscall compatible with V7 but IIRC it didn't have any sort of memory protection as it was designed to run on 8088.
Minux and specifically M1 was and always has been, a uK. And yes, M1 does not need an MMU - since it was designed to run on an 8088. IIRC this was Linus' original objection when he wanted to run on his 386-based PC (Wyse 32:16 box, IIRC). The key was Andy wanted to teach his students about V7 without running afoul of the AT&T license as Lions had with V6.
What runs on the Intel Management Engine
is MINIX 3, ... with NetBSD userland.
Actually, if you want to pick nits, neither statement is correct (remember for whom I work).
MINIX 1 and MINIX 3 are related
That's because M3 added the MMU support that M1 lacked. But there is nothing in M3 that IPMI is using other than it is the current version from Andy's team. What IPMI has as an underlying uK is heavily hacked and is a 'derivative work' - the local uk is basically providing V7 interfaces to some special programs.
It made little sense to recreate something for the platform engine, and Minux was picked because it was smaller than any of the *BSDs and was not GPL'ed so Intel IP was still protected.
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