From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Lameter <clameter@sgi.com>
Subject: Re: EMM: disable other notifiers before register and unregister
Date: Thu, 3 Apr 2008 13:23:12 -0700 (PDT)
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On Thu, 3 Apr 2008, Christoph Lameter wrote:

> > faults). So it should be ok to take all those locks inside the
> > mmap_sem and implement a lock_vm(mm) unlock_vm(mm). I'll think more
> > about this hammer approach while I try to implement it...
> 
> Well good luck. Hopefully we will get to something that works.

Another hammer to use may be the freezer from software suspend. With that 
you can get all tasks of a process into a definite state. Then take the 
mmap_sem writably. But then there is still try_to_unmap and friends that 
can race.