[RFC/PATCH 8/14] powerpc: Fix kmalloc alignmenent on non-coherent DMA
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2007-11-21 06:16:27
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