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Date: Thu, 15 May 2008 10:33:57 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
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To: Nick Piggin <npiggin@suse.de>
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Subject: Re: [PATCH 08 of 11] anon-vma-rwsem
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On Thu, 15 May 2008, Nick Piggin wrote:

> Oh, I get that confused because of the mixed up naming conventions
> there: unmap_page_range should actually be called zap_page_range. But
> at any rate, yes we can easily zap pagetables without holding mmap_sem.

How is that synchronized with code that walks the same pagetable. These 
walks may not hold mmap_sem either. I would expect that one could only 
remove a portion of the pagetable where we have some sort of guarantee 
that no accesses occur. So the removal of the vma prior ensures that?