On Mon, Mar 16, 2020 at 09:50:10PM +0530, Krishnamraju Eraparaju wrote: > > I'm seeing broken CRCs at NVMeF target while running the below program > at host. Here RDMA transport is SoftiWARP, but I'm also seeing the > same issue with NVMe/TCP aswell. > > It appears to me that the same buffer is being rewritten by the > application/ULP before getting the completion for the previous requests. > getting the completion for the previous requests. HW based > HW based trasports(like iw_cxgb4) are not showing this issue because > they copy/DMA and then compute the CRC on copied buffer. For TCP we can set BDI_CAP_STABLE_WRITES. For RDMA I don't think that is a good idea as pretty much all RDMA block drivers rely on the DMA behavior above. The answer is to bounce buffer the data in SoftiWARP / SoftRoCE.
