[ofa-general] iSER data corruption issues

[Roland Dreier]

 > I would look into the dma_sync behavior on the receiver. Especially
 > on an Opteron, it's critical to synchronize the iommu and cachelines
 > to the right memory locations. Since the FMR code hides some of
 > this, it may be a challenge to trace. Can you try another memory
 > registration strategy? NFS/RDMA can do that, for example.

I think this is a red herring.  Every IB HCA does 64-bit DMA, which
means it bypasses all the Opteron iommu/swiotlb stuff.

Also FMR doesn't hide any DMA mapping stuff; it is completely up to
the consumer to handle all the DMA mapping, because FMRs operate
completely at the level of bus (HCA DMA) addresses.

 - R.