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Date: Tue, 9 Aug 2005 15:50:47 +0100 (BST)
From: Hugh Dickins <hugh@veritas.com>
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To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
cc: Nick Piggin <nickpiggin@yahoo.com.au>, Daniel Phillips <phillips@arcor.de>,
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       Linus Torvalds <torvalds@osdl.org>, Andrew Morton <akpm@osdl.org>,
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Subject: Re: [RFC][patch 0/2] mm: remove PageReserved
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On Tue, 9 Aug 2005, Benjamin Herrenschmidt wrote:
> 
> > But you don't mind if they are refcounted, do you?
> > Just so long as they start out from 1 so never get freed.
> 
> Well, a refcounting bug would let them be freed and kaboom ... That's
> why a "PG_not_your_ram_dammit" bit would be useful. It could at least
> BUG_ON when refcount reaches 0 :)

Okay, great, let's give every struct page two refcounts,
so if one of them goes wrong, the other one will save us.

Hugh