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Date: Thu, 3 Aug 2006 09:07:06 +0000 (GMT)
From: moreau francis <francis_moreau2000@yahoo.fr>
Reply-To: moreau francis <francis_moreau2000@yahoo.fr>
Subject: Re : Re : sparsemem usage
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: linux-kernel@vger.kernel.org, apw@shadowen.org
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Alan Cox wrote:
>
> Mapping out parts of a section is quite normal - think about the 640K to
> 1Mb hole in PC memory space.

OK. But I'm still worry. Please consider the following code

       for (...; ...; ...) {
                [...]
                if (pfn_valid(i))
                       num_physpages++;
                [...]
        }

In that case num_physpages won't store an accurate value. Still it will be
used by the kernel to make some statistic assumptions on other kernel
data structure sizes.

Francis