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Subject: Re: [PATCH] Fix mmap_kmem (was: [question] What's the difference
	between /dev/kmem and /dev/mem)
From: Arjan van de Ven <arjan@infradead.org>
To: Linus Torvalds <torvalds@osdl.org>
Cc: Steven Rostedt <rostedt@goodmis.org>, LKML <linux-kernel@vger.kernel.org>,
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Date: Sat, 13 Aug 2005 20:18:07 +0200
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On Sat, 2005-08-13 at 10:37 -0700, Linus Torvalds wrote:
> 
> On Sat, 13 Aug 2005, Arjan van de Ven wrote:
> > 
> > attached is the same patch but now with Steven's change made as well
> 
> Actually, the more I looked at that mmap_kmem() function, the less I liked 
> it.  Let's get that sucker fixed better first. It's still not wonderful, 
> but at least now it tries to verify the whole _range_ of the mapping.

actually if that is your goal this just isn't enough... assume the
situation of a 1 page "forbidden gap", if you mmap 3 pages with the gap
in the middle.... then the code you send still doesn't cope. At which
point... it gets messy...