Fix linux-arm-kernel address.

On Fri, Jan 21, 2011 at 2:43 AM, Minchan Kim [off-list ref] wrote:

Restore Cced.

On Fri, Jan 21, 2011 at 2:24 AM, KyongHo Cho [off-list ref] wrote:

quoted

On Thu, Jan 20, 2011 at 11:28 PM, Minchan Kim [off-list ref] wrote:

quoted

On Thu, Jan 20, 2011 at 06:45:39PM +0900, KyongHo Cho wrote:

quoted

Sparsemem allows that a bank of memory spans over several adjacent
sections if the start address and the end address of the bank
belong to different sections.
When gathering statictics of physical memory in mem_init() and
show_mem(), this possiblity was not considered.

Please write down the result if we doesn't consider this patch.
I can understand what happens but for making good description and review,
merging easily, it would be better to write down the result without
the patch explicitly.

As we know that each section has its own memmap and
a contiguous chunk of physical memory that is represented by 'bank' in meminfo
can be larger than the size of a section.
"page++" in the current implementation can access invalid memory area.
The size of the section is 256 MiB in ARM and the number of banks in
meminfo is 8.
This means that the maximum size of the physical memory cannot be grow than 2GiB
to avoid this problem in the current implementation.
Thus we need to fix the calculation of the last page descriptor in
terms of sections.

This patch determines the last page descriptor in a memmap with
min(last_pfn_of_bank, last_pfn_of_current_section)
If there remains physical memory not consumed, it calculates the last
page descriptor
with min(last_pfn_of_bank, last_pfn_of_next_section).

quoted

Hmm.. new ifndef magic makes code readability bad.
Couldn't we do it by simple pfn iterator not page and pfn_valid check?

True.
We need to consider the implementation again.
I think the previous implementation gave the importance to the
efficiency but to the readability.

Please consider readability and consistency with other architectures
if we can do. :)
Thanks.

--
Kind regards,
Minchan Kim

-- 
Kind regards,
Minchan Kim

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