Slab errors on 4xx (STB04)
Eugene Surovegin
ebs at ebshome.net
Mon Apr 10 17:14:57 EST 2006
On Mon, Apr 10, 2006 at 12:33:56AM +0200, Andre Draszik wrote:
>
> Since it _seems_ to work nevertheless - is CONFIG_DEBUG_SLAB known to be
> broken on this platform?
Yes, it's very likely that CONFIG_DEBUG_SLAB is the culprit here. This
config option changes allocation alignment (it becomes not L1 cache
line aligned). For 4xx which has non-coherent L1 cache this with
almost 100% probability will break DMA, resulting in memory
corruption.
You can try changing __dma_sync() to do flush_dcache_range() even for
DMA_FROM_DEVICE case. However, do this only to check this theory, not
as a permanent solution :).
--
Eugene
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