Memory management (segmentation and paging) in 80286 and 80386: How does it work?

Posted by Andrew J. Brehm on Super User See other posts from Super User or by Andrew J. Brehm
Published on 2011-02-07T13:42:27Z Indexed on 2011/02/07 15:27 UTC
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memory-management

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real-mode

I found lots of Web sites and books explaining how memory management worked on the 8086 and later x86 CPUs in Real Mode. I understand, I think, how two 16 bit values, segment address and offset are combined to get a linear 20 bit physical address (shift segment four bits to the left, add offset; segments are 64K and start every 16 bytes).

But I couldn't find any good Web sites or books that explained how memory management works in Protected Mode, specifically the differences between 80286 and 80386.

Can anyone point me to a good Web site or book (or explain it right here)?

(For extra credit, i.e. an upvote, how does it work in Long Mode?)

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