From: David Woodhouse Subject: Re: [BUG] SLOB breaks Crypto Date: Wed, 19 May 2010 12:40:36 +0100 Message-ID: <1274269236.6930.9930.camel@macbook.infradead.org> References: <1274211235.11603.1205.camel@calx> <20100518.135945.180391159.davem@davemloft.net> <20100518.142021.135951273.davem@davemloft.net> <1274224834.6930.8361.camel@macbook.infradead.org> <20100519010524.GB18813@gondor.apana.org.au> <1274253269.6930.9325.camel@macbook.infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Herbert Xu , David Miller , penberg@cs.helsinki.fi, mpm@selenic.com, ken@codelabs.ch, michael-dev@fami-braun.de, linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, anemo@mba.ocn.ne.jp To: Geert Uytterhoeven Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org 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?=20 What is 'correct'? The architecture sets it to the minimum value that i= t can cope with, according to its own alignment constraints (and DMA/cach= e 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'=C3=AAtre. --=20 dwmw2