That's a <i>lot</i> of information in a single email! Really nice, especially the history, virtual memory and nommu stuff. I recently implemented an ELF I/O library and was forced to learn a not insignificant fraction of all that from the specification and scattered resources... An email like this would have made things so much easier.
> Some old processors had page fault handling in hardware. This sucked rocks, and
Linus yelled at the PowerPC guys somewhat extensively about this 20 years ago.<p>Wait, wasn't it the other way around? I might be mistaken but wasn't one of the problems with PowerPC that it only really had a TLB and the kernel had to walk the page tables in software?<p>Afaik on x86 the page fault handler is only called when a page isn't marked present, so that one can allocate a new page/load the page from mass storage, but apart from that walking the page tables is done in hardware.<p>Has been a while since I've only really dabbled in 32-bit protected mode a decade or so ago so I might be misremembering.