On Wed, Jun 17, 2015 at 05:34:02PM +0200, Boris Brezillon wrote:

I can check for that too, but note that it doesn't prevent one from
providing different scatterlist structures pointing to the same memory
region.

Pointing to the same memory should be fine, it's the act of passing
the same SG list to dma_map_sg twice that's wrong because dma_map_sg
will modify the SG list.

Cheers,
-- 
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