Re: [PATCH] Tight check of pfn_valid on sparsemem - v4

[Minchan Kim]

Hi, Kame.

On Tue, Jul 27, 2010 at 5:13 PM, KAMEZAWA Hiroyuki
<kamezawa.hiroyu@xxxxxxxxxxxxxx>
>> Perhaps the mem_section array.  Using a symbol that is part of
>> the model pre-checks can remove a global symbol lookup and has the side
>> effect of making sure our pfn_valid is for the right model.
>>
>
> But yes, maybe it's good to make use of a fixed-(magic)-value.

fixed-magic-value?
Yes. It can be good for some debugging.
But as Christoph pointed out, we need some strict check(ex,
PG_reserved) for preventing unlucky valid using of magic value in
future.
But in fact I have a concern to use PG_reserved since it can be used
afterward pfn_valid normally to check hole in non-hole system. So I
think it's redundant.

Hmm..

-- 
Kind regards,
Minchan Kim
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