From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Y. D." <duyuyang@gmail.com>
Subject: Different: nr_pages vs. max_pfn
Date: Wed, 19 Nov 2008 17:45:50 +0800
Message-ID: <200811191745479618049@gmail.com>
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Hi,

In start_info, there is a field nr_pages definig how much memory is allocated to the domain, which is obvious.
While in shared_info, there is a field max_pfn. I don't know why max_pfn is not equal to nr_pages.
Say for 32MB memory, nr_pages = 8192, while max_pfn = 10240 (may vary?), of which 2048 pfn's have invalid mfn.
Can anybody explain that why max_pfn is larger? Is it static or dynamic?
Furture, does pfn to mfn frame mapping ever change? Hopefully not.

Thanks,
Shawn