Crispin Cowan wrote:
Of particular and critical interest at this juncture is segmented
memory. Graybeards love segmented memory, and modern Linux kidz hate
segmented memory. A close friend has observed to me that 100% of A1
evaluated operating systems (both of them :) used segmented memory. In
stark contrast, all modern operating systems use paged memory instead.
Apparently there was a movement to hack segments into the Linux kernel a
year or so ago, but it was quickly shouted down.
I thought I had the right x86 brain-damage, and knew what segments were.
But it doesn't sound like what you are describing. My memory of
segments has to do with a painful way to address 64K at a time on 16-bit
DOS. As opposed to a nice flat 32-bit (or more) address space.
Are you proposing that were I to access a memory address with DS: that I
get one set of privs, and if I used ESI: I get a different set?
And what does that have to do with paging, which I thought had to do
with mapping between physical and logical memory?
I'm not trying to flame you Crispin, I'd be willing to bet money that
I'm the one who knows less in this area. But I don't think you're
explaining what you are getting at well. Please spell it out for me.
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