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Subject: Re: PPC: slab error in cache_free_debugcheck() from
	sd_revalidate_disk
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Manfred Spraul <manfred@colorfullife.com>
Cc: John Mock <kd6pag@qsl.net>,
       Linux Kernel list <linux-kernel@vger.kernel.org>
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> That looks like a bug Ben reported some time ago: The dma controller 
> trashes the whole cacheline when it transfers data from disk to memory.
> I think the only solution is to disable redzoning for the kmalloc 
> caches, or to use get_free_pages instead of kmalloc for the disk buffers,.

Looks like it indeed. I will probably send a patch to use get_free_page()
instead one of these days (after I've moved)

Ben.