Re: [GIT PULL] x86 setup: correct booting on 486DX4

[Jeremy Fitzhardinge]

Linus Torvalds wrote:
> I'm not entirely sure that it needs to be a long-jump, btw. I think any
> regular branch is sufficient. You obviously *do* need to make the long 
> jump later (to reload %cs in protected mode), but I'm not sure it's needed 
> in that place. I forget the exact rules (but they definitely were 
> documented).

Yes, it says it needs to be a far jmp or call (and if you enabled paging
in the cr0 load, you need to identity-map the branch target).  Having
successfully broken the rules for a long time so far, maybe we can get
away with still cutting corners...  but it doesn't seem particularly
worthwhile since we've been caught once.

    J
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