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To: <linuxppc-dev@ozlabs.org>
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Mon, 19 Nov 2007 19:25:06 +1100
Subject: [RFC/PATCH 7/9] powerpc: Fix kmalloc alignmenent on non-coherent DMA
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On platforms doing non-coherent DMA (4xx, 8xx, ...), it's important that
kmalloc minimum alignment is set to the cache line size, to avoid sharing
cache lines between different objects.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---

 include/asm-powerpc/page_32.h |    4 ++++
 1 file changed, 4 insertions(+)

Index: linux-work/include/asm-powerpc/page_32.h
===================================================================
--- linux-work.orig/include/asm-powerpc/page_32.h	2007-11-19 15:01:08.000000000 +1100
+++ linux-work/include/asm-powerpc/page_32.h	2007-11-19 15:01:17.000000000 +1100
@@ -6,6 +6,10 @@
 
 #define PPC_MEMSTART	0
 
+#ifdef CONFIG_NOT_COHERENT_CACHE
+#define ARCH_KMALLOC_MINALIGN	L1_CACHE_BYTES
+#endif
+
 #ifndef __ASSEMBLY__
 /*
  * The basic type of a PTE - 64 bits for those CPUs with > 32 bit