Re: [PATCH 1/2] doc: update mem= option's spec

From: Rob Landley
Date: Thu Jun 14 2012 - 16:22:44 EST


On 06/14/2012 03:10 AM, Wen Congyang wrote:
> Current mem= implementation seems buggy because specification and
> implementation doesn't match. Current mem= has been working
> for many years and it's not buggy, it works as expected. So
> we should update the specification.
>
> Signed-off-by: Wen Congyang <wency@xxxxxxxxxxxxxx>
> ---
> Documentation/kernel-parameters.txt | 7 ++++---
> 1 files changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
> index a92c5eb..924b1a4 100644
> --- a/Documentation/kernel-parameters.txt
> +++ b/Documentation/kernel-parameters.txt
> @@ -1471,9 +1471,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
> mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
> Amount of memory to be used when the kernel is not able
> to see the whole system memory or for test.
> - [X86-32] Use together with memmap= to avoid physical
> - address space collisions. Without memmap= PCI devices
> - could be placed at addresses belonging to unused RAM.
> + [X86-32] Work as limiting max address. Use together
> + with memmap= to avoid physical address space collisions.
> + Without memmap= PCI devices could be placed at addresses
> + belonging to unused RAM.
>
> mem=nopentium [BUGS=X86-32] Disable usage of 4MB pages for kernel
> memory.

I have no objection to this but can't confirm it's true or not without
an awful lot more digging through the code I don't have time for right
now. (All the x86-32 machines I've used just had the 640k->1m hole and
the rest was contiguous memory, so the behavior would be the same either
way...)

Sort-of-tentatively-acked-by: Rob Landley <rob@xxxxxxxxxxx>

Rob
--
GNU/Linux isn't: Linux=GPLv2, GNU=GPLv3+, they can't share code.
Either it's "mere aggregation", or a license violation. Pick one.
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