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Re: [MiNT] Memory protection for the FireBee?

... and - just to add another level of complexity - Linux (and other decent operating systems) for sure don't have stupid system calls like Super() that allow arbitrary user processes to go into supervisor mode at their own desire and open up a supervisor stack at arbirtrary memory addresses.

Am 26.08.2015 um 11:36 schrieb markus@mubf.de:
Not sure, but I think with Linux, it's basically just the other way round.

I guess for Linux, the m68k way of handling page table descriptors is foreign since the Coldfire MMU works very similar like most (at least most of I know about) modern processor architectures do.

One can argue if this was the reason for Freescale to make it work like it does.

Am 26.08.2015 um 10:59 schrieb Miro Kropáček:
Thanks Markus for the great description of the problem!

On Wed, Aug 26, 2015 at 10:51 AM, markus@mubf.de <markus@mubf.de> wrote:
I'm not saying it would be impossible (it definitely could be made), it's just that its a _real huge_ load of work.

I'm curious here -- how it's handled in other m68k-compatible OSes? Like NetBSD, Linux? I doubt there are significant differences between 680x0 and CF, from what I've seen (and remember), all those OSes expect only a very small amount of low-level / CPU specific code written.

MiKRO / Mystic Bytes