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Subject: Re: [patch 3/4 -mm] flex_array: poison free elements
From: Dave Hansen <dave@linux.vnet.ibm.com>
To: David Rientjes <rientjes@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, linux-kernel@vger.kernel.org
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Date: Wed, 09 Sep 2009 12:22:37 -0700
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On Wed, 2009-09-09 at 12:18 -0700, David Rientjes wrote:
> On Wed, 9 Sep 2009, Dave Hansen wrote:
> > I don't know of any offhand.  Someone mentioned oprofile buffers at some
> > point, but I looked through it and it didn't pop out at me.
> 
> Their length and element size fit the prerequisites of using flex array, 
> but they cannot be copied to userspace as a string the way we can with 
> vmalloc'd memory.

It shouldn't be too hard to do that, though.  Although a bit silly to
have make a copy_to_user() call for each ->parts[] page, it would be
pretty easy to implement.  

-- Dave