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Subject: Re: About get_page for compound page
From: Peter Zijlstra <peterz@infradead.org>
To: Fengwei Yin <yfw.kernel@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>
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Date: Thu, 19 Jul 2007 23:39:32 +0200
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On Thu, 2007-07-19 at 23:54 +0800, Fengwei Yin wrote:
> Hi,
> In get_page(), the parameter page is changed by
>          page = compound_head(page);
> if the page is not the first page of compound pages.
> 
> My question: is this behavior correct?

Yes it is, in general the page state of a compound page is kept in the
first page of the set.