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Subject: Re: [BUG] SLOB breaks Crypto
From: David Woodhouse <dwmw2@infradead.org>
To: Geert Uytterhoeven <geert@linux-m68k.org>
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Date: Wed, 19 May 2010 12:40:36 +0100
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On Wed, 2010-05-19 at 13:32 +0200, Geert Uytterhoeven wrote:
> Instead of having (different) defaults in sl[aou]b, perhaps we should
> just remove the defaults completely, to ensure all architectures set
> ARCH_SLAB_MINALIGN to the correct value? 

What is 'correct'? The architecture sets it to the minimum value that it
can cope with, according to its own alignment constraints (and DMA/cache
constraints, in the case of ARCH_KMALLOC_MINALIGN).

Some architectures don't _have_ any minimum required alignment, so they
have no need to set it. If the architecture _does_ specify a minimum,
the allocators must honour it. Otherwise, they're free to do their own
thing. And slob chooses to use a smaller alignment than slab and slub
do, in accordance with its design and its raison d'être.

-- 
dwmw2