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Date: Thu, 22 May 2008 09:51:21 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
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To: Pekka Enberg <penberg@cs.helsinki.fi>
cc: Matt Mackall <mpm@selenic.com>, Paul Mundt <lethal@linux-sh.org>,
       linux-kernel@vger.kernel.org, dhowells@redhat.com
Subject: Re: [RFC/PATCH 1/3] SLAB: Add PageSlab checking to ksize()
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On Thu, 22 May 2008, Pekka Enberg wrote:

> Hi Matt,
> 
> On Thu, May 22, 2008 at 6:01 PM, Matt Mackall <mpm@selenic.com> wrote:
> > As I've said several times, ksize() on kmem_cache_alloced objects
> > -cannot work- on SLOB. Calling ksize() on something returned by
> > kmem_cache_alloc is a categorical error.
> 
> Well, it's a historical fact that ksize() worked for both kmalloc()
> and kmem_cache_alloc() (see the kernedoc comment in mm/slab.c).
> However, I think we should just look at getting rid of ksize()
> altogether as it's only (ab)used by the nommu code and few call-sites
> that open-code krealloc().

Good idea. if krealloc is an allocator internal function then it can 
establish the size as needed and we do not have ksize available.