From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [patch] rd: support XIP
Date: Tue, 4 Dec 2007 03:26:20 -0800
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Cc: Christian Borntraeger <borntraeger@de.ibm.com>,
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	linux-fsdevel@vger.kernel.org,
	"Eric W. Biederman" <ebiederm@xmission.com>, rob@landley.net,
	Jens Axboe <axboe@kernel.dk>
To: Nick Piggin <npiggin@suse.de>
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On Tue, 4 Dec 2007 12:21:00 +0100 Nick Piggin <npiggin@suse.de> wrote:

> +	 *
> +	 * Cannot support XIP and highmem, because our ->direct_access
> +	 * routine for XIP must return memory that is always addressable.
> +	 * If XIP was reworked to use pfns and kmap throughout, this
> +	 * restriction might be able to be lifted.
>  	 */
> +	gfp_flags = GFP_NOIO | __GFP_ZERO;
> +#ifndef CONFIG_BLK_DEV_XIP
> +	gfp_flags |= __GFP_HIGHMEM;
> +#endif

A dubious tradeoff?