Messages in this thread | | | Date | Thu, 5 Feb 2009 20:51:40 +0000 (GMT) | From | Hugh Dickins <> | Subject | Re: pud_bad vs pud_bad |
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On Thu, 5 Feb 2009, Jeremy Fitzhardinge wrote: > Hugh Dickins wrote: > > However... I forget how the folding works out. The pgd in the 32-bit > > PAE case used to have just the pfn and the present bit set in that > > little array of four entries: if pud_bad() ends up getting applied > > to that, I guess it will blow up. > > Ah, that's a good point. > > > If so, my preferred answer would actually be to make those 4 entries > > look more like real ptes; but you may think I'm being a bit silly. > > Hardware doesn't allow it. It will explode (well, trap) if you set anything > other than P in the top level.
Oh, interesting, I'd never realized that.
> By the by, what are the chances we'll be able to deprecate non-PAE 32-bit?
I sincerely hope 0! I shed no tears at losing support for NUMAQ, but why should we be forced to double all the 32-bit ptes? You want us all to be using NX? Or you just want to cut your test/edit matrix - that I can well understand!
Hugh
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