On Wed, 23 Jan 2008, Pekka Enberg wrote:

I think Mel said that their configuration did work with 2.6.23
although I also wonder how that's possible. AFAIK there has been some
changes in the page allocator that might explain this. That is, if
kmem_getpages() returned pages for memoryless node before, bootstrap
would have worked.

Regular kmem_getpages is called with GFP_THISNODE set. There was some 
breakage in 2.6.22 and before with GFP_THISNODE returning pages from the 
wrong node if a node had no memory. So it may have worked accidentally and 
in an unsafe manner because the pages would have been associated with the 
wrong node which could trigger bug ons and locking troubles.