Christoph, I was able to bisect this to your patch "scsi: reduce use of block bounce buffers". I am getting the error on a 32-bit Dell PowerEdge 6650. It has the aic7xxx integrated onto the motherboard. Again, here is the error: aic7xxx 0000:00:03.0: dma_direct_map_sg: overflow 0x00000003ff800000+65536 of device mask ffffffff I wonder if the odd 39-bit mask used in aic7xxx is part of the problem? - Matthew