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SubjectRe: [PATCH 4/3] x86/mm/doc: Enhance the x86-64 virtual memory layout descriptions

* Ingo Molnar <mingo@kernel.org> wrote:

> +========================================================
> +| Complete virtual memory map with 4-level page tables |
> +========================================================

> +--------------------------------------------------------------------------------
> +start addr | offset | end addr | size | VM area description
> +-----------------|------------|------------------|---------|--------------------

> +
> +# Identical layout to the 56-bit one from here on:
> +
> +ffffff8000000000 | -512 GB | fffffffeefffffff | ~507 GB | ... unused hole
> +ffffffef00000000 | -68 GB | fffffffeffffffff | 64 GB | EFI region mapping space

> +========================================================
> +| Complete virtual memory map with 5-level page tables |
> +========================================================

> +ffffff8000000000 | -0.5 TB | ffffffeeffffffff | 444 GB | ... unused hole
> +
> +# Identical layout to the 47-bit one from here on:
> +
> +ffffffef00000000 | -68 GB | fffffffeffffffff | 64 GB | EFI region mapping space

So patch #2 appears to have introduced an error/typo in the 47-bit table. Note the weird size
and discontinuity of the 'unused hole' in the 47-bit table, and compare it with 56-bit table:

fffffffeefffffff
ffffffeeffffffff

(Note how the incorrect end address was cargo-cult-copied into the 'size' field of ~507 GB...)

The correct number is the 56-bit one, and both tables should show the following identical
layout:

ffffff8000000000 | -512 GB | fffffffeefffffff | 444 GB | ... unused hole
ffffffef00000000 | -68 GB | fffffffeffffffff | 64 GB | EFI region mapping space

Agreed?

Thanks,

Ingo

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