Subject: Re: [patch 3/3] mm: fault handler to replace nopage and populate
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Thomas =?ISO-8859-1?Q?Hellstr=F6m?= <thomas@tungstengraphics.com>
Cc: Nick Piggin <npiggin@suse.de>, Andrew Morton <akpm@osdl.org>,
       Linux Memory Management <linux-mm@kvack.org>,
       Linux Kernel <linux-kernel@vger.kernel.org>
In-Reply-To: <452B398C.4030507@tungstengraphics.com>
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Date: Tue, 10 Oct 2006 17:55:31 +1000
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> Still, even with NOPAGE_REFAULT or the equivalent with the new fault() code,
> in the case we need to take this route, (and it looks like we won't have 
> to),
> I guess we still need to restart from find_vma() in the fault()/nopage() 
> handler to make sure the VMA is still present. The object mutex need to 
> be dropped as well to avoid deadlocks. Sounds complicated.

But as we said, it should be enough to do the flag change with the
object mutex held as long as it's after unmap_mapped_ranges()

Ben.


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