Re: [PATCH 00 of 10] x86: unify asm/pgtable.h

From: Jeremy Fitzhardinge
Date: Tue Jan 08 2008 - 18:25:08 EST


Ingo Molnar wrote:
threw this into the random test setup: it found the attached config after a few iterations, which needed the fix below. (config builds and boots fine with this fix)

the problem was that set_pud() is used by include/asm-generic/pgtable-nopud.h, to build set_pgd():

#define set_pgd(pgdptr, pgdval) set_pud((pud_t *)(pgdptr), (pud_t) { pgdval })

Oh, yeah. That's bitten me before, but I guess I lost that part of the patch somewhere :(.

it's truly a maze ... took me 10 straight minutes of staring at the code to figure out where the set_pud() came from :-/

It's pretty awful. The pagetable level folding stuff is fairly deep into "too clever" territory, but its hard to see what better alternatives there are... Dropping non-PAE support would be nice, but impractical given that even relatively recent chips are missing support for it.

anyway, your patchset is holding up pretty good so far in testing.

Great!

J
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/