From mboxrd@z Thu Jan  1 00:00:00 1970
From: Roland Dreier <rdreier@cisco.com>
Subject: Re: Question regarding SLAB corruption
Date: Mon, 09 Jul 2007 12:21:11 -0700
Message-ID: <adak5t9z8m0.fsf@cisco.com>
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To: Keir Fraser <keir@xensource.com>
Cc: Lukas Hejtmanek <xhejtman@ics.muni.cz>, xen-devel@lists.xensource.com
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 > By my understanding, the infiniband driver is doing an order-6 allocation,
 > then stuffing that multi-page region into a single element of a scatterlist.
 > It is then calling dma_map_sg(), which [on Xen] calls swiotlb_map_sg(),
 > which calls map_single() on that multi-page extent. Am I misunderstanding
 > something?

Don't know about the Xen part but you are correct about the mthca
driver part.  And as far as I know it is perfectly fine to put order>0
pages into a scatterlist...

 - R.