From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dave Hansen <haveblue@us.ibm.com>
Subject: Re: [patch 3/9] Guest page hinting: volatile page cache.
Date: Fri, 01 Sep 2006 07:57:47 -0700
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To: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: linux-kernel@vger.kernel.org, virtualization@lists.osdl.org, akpm@osdl.org, nickpiggin@yahoo.com.au, frankeh@watson.ibm.com, rhim@cc.gateh.edu, Andy Whitcroft <apw@shadowen.org>
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On Fri, 2006-09-01 at 13:09 +0200, Martin Schwidefsky wrote:
> +#define PG_state_change                21      /* HV page state is changing. */
> +#define PG_discarded           22      /* HV page has been discarded. */ 

We're already desperately short on page flags on 32-bit architectures.
It seems a wee bit silly to add two arch-generic flags for what is a
very specialized arch-specific feature at this point.

I know that there are 32-bit s390 kernels, but would this be a
reasonable feature to restrict to only 64-bit kernels?  That might be a
decent compromise.

-- Dave