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Date: Wed, 3 Aug 2005 09:39:03 -0700 (PDT)
From: Linus Torvalds <torvalds@osdl.org>
To: Nick Piggin <nickpiggin@yahoo.com.au>
cc: Hugh Dickins <hugh@veritas.com>,
       Martin Schwidefsky <schwidefsky@de.ibm.com>,
       Andrew Morton <akpm@osdl.org>, Robin Holt <holt@sgi.com>,
       linux-kernel <linux-kernel@vger.kernel.org>, linux-mm@kvack.org,
       Ingo Molnar <mingo@elte.hu>, Roland McGrath <roland@redhat.com>
Subject: Re: [patch 2.6.13-rc4] fix get_user_pages bug
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On Wed, 3 Aug 2005, Linus Torvalds wrote:
> 
> Ok, I applied this because it was reasonably pretty and I liked the 
> approach. It seems buggy, though, since it was using "switch ()" to test 
> the bits (wrongly, afaik), and I'm going to apply the appended on top of 
> it. Holler quickly if you disagreee..

Another problem I just thought of.

What about PROT_NONE pages? Afaik, they have _exactly_ the same issue on 
the read side as a PROT_READ page has on the write side: pte_read() may 
fail on them.

What makes us not get into an infinite loop there? 

		Linus