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From: Christoph Lameter <cl@linux.com>
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To: Dave Hansen <dave@sr71.net>
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Subject: Re: [RFC][PATCH 5/9] mm: rearrange struct page
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On Thu, 16 Jan 2014, Dave Hansen wrote:

> Why does it matter *specifically* that "index shares space with
> freelist", or that "mapping shares space with s_mem"?  No data is ever
> handed off in those fields.

If the field is corrupted then one needs to figure out what other ways of
using this field exists. If one wants to change the page struct fields
then also knowlege about possible interconnections are important.