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Date: Mon, 09 Sep 2002 23:19:25 +0200
From: Manfred Spraul <manfred@colorfullife.com>
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To: linux-kernel@vger.kernel.org, Andrew Morton <akpm@digeo.com>
Subject: Re: Calculating kernel logical address ..
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Andrew Morton wrote:
> Nobody seems to have come forth to implement a thought-out scatter/gather,
> map-user-pages library infrastructure so I'd be a bit reluctant to
> break stuff without offering a replacement.
> 

We'd need one.

get_user_pages() is broken if a kernel module access the virtual address 
of the page and the cpu caches are not coherent:
Most of the flush functions need the vma pointer, but it's impossible to 
guarantee that it still exists when the get_user_pages() user calls 
page_cache_release().

--
	Manfred

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