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Date: Tue, 1 Aug 2006 22:08:33 +0300
From: "Pekka Enberg" <penberg@cs.helsinki.fi>
To: "Christoph Lameter" <clameter@sgi.com>
Subject: Re: Re: [BLOCK] bh: Ensure bh fits within a page
Cc: "Andrew Morton" <akpm@osdl.org>,
       "Herbert Xu" <herbert@gondor.apana.org.au>,
       linux-kernel@vger.kernel.org, ext2-devel@lists.sourceforge.net
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Hi,

On 8/1/06, Christoph Lameter <clameter@sgi.com> wrote:
> The slab allocator gives no guarantee that a structure is not straddling a
> page boundary regardless of debug or not. It may just happen that the
> objects are arranged if kmem_cache_cretae() is called with certain
> parameters. Another arch with other cacheline alignment and another page
> size may arrange the objects differently.

Indeed. You could try to force zero-order page allocations for a
cache, but we are probably better of using the page allocator directly
or crafting a special purpose allocator for the block layer.

                                 Pekka