From: FUJITA Tomonori
Date: Wed May 19 2010 - 23:21:00 EST

As DMA-API-HOWTO says, kmalloc'ed buffer must be DMA-safe. Drivers and
subsystems depend on it.

So architectures that handle DMA-non-coherent memory need to set
ARCH_KMALLOC_MINALIGN: the kmalloc'ed buffer doesn't share a cache
with the others. Otherwise, we hit memory corruption due to DMA.

I had a quick look at all the architectures. Seems that some
architectures that need to set ARCH_KMALLOC_MINALIGN don't do.

arch/blackfin/include/asm/cache.h | 2 ++
arch/frv/include/asm/cache.h | 2 ++
arch/m68k/include/asm/cache.h | 2 ++
arch/mn10300/include/asm/cache.h | 2 ++
arch/parisc/include/asm/cache.h | 2 ++
arch/xtensa/include/asm/cache.h | 1 +
6 files changed, 11 insertions(+), 0 deletions(-)
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