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Date: Tue, 30 Aug 2005 21:09:39 +0200
From: Christoph Hellwig <hch@lst.de>
To: Nicolas DET <nd@bplan-gmbh.de>
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Cc: akpm@osdl.org, linuxppc-dev@ozlabs.org, Sven Luther <sl@bplan-gmbh.de>,
	Kumar Gala <galak@freescale.com>
Subject: Re: Marvell MV6436xx ethernet driver patch
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On Tue, Aug 30, 2005 at 08:07:33PM +0100, Nicolas DET wrote:
> By the way, I noticed that page_address() sometimes returns NULL when using
> highmem (with a lot of mem).

You can only use page_address() on kernel-mapped memory.  For
non-GFP_KERNEL allocation you need to use kmap/kmap_atomic to map it
into kernel-virtual memory space.