This change,

  commit 20c2df83d25c6a95affe6157a4c9cac4cf5ffaac
  Author: Paul Mundt <lethal@linux-sh.org>
  Date:   Fri Jul 20 10:11:58 2007 +0900
  
      mm: Remove slab destructors from kmem_cache_create().
      
removed the penultimate parameter to kmem_cache_create, so we
just need to drop one of the NULL function pointers in our call.

It seems Mundt missed the aoe driver.  More work for me!