Re: [i386] Questions regarding provisional page tables initialization

Andreas Schwab
2007-07-01T22:02:38Z

"Ahmed S. Darwish" <darwish.07@gmail.com> writes:

> page_pde_offset = (__PAGE_OFFSET >> 20)
> movl %ecx,(%edx) /* Store identity PDE entry */
> movl %ecx,page_pde_offset(%edx) /* Store kernel PDE entry */
>
> Why the pde_offset is PAGE_OFFSET >> 20 instead of PAGE_OFFSET >> 22 ?
> * 22 to right shift the whole page_shift (12) and pgdir_shift (10) bits.

4 is the element size.

Andreas.

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Andreas Schwab, SuSE Labs, schwab@suse.de
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