On Wed, Dec 04, 2019 at 12:23:39PM -0500, Stephen Rust wrote: > Hi Ming, > > I have tried your latest "workaround" patch in brd including the fix > for large offsets, and it does appear to work. I tried the same tests > and the data was written correctly for all offsets I tried. Thanks! > > I include the updated additional bpftrace below. > > > So firstly, I'd suggest to investigate from RDMA driver side to see why > > un-aligned buffer is passed to block layer. > > > > According to previous discussion, 512 aligned buffer should be provided > > to block layer. > > > > So looks the driver needs to be fixed. > > If it does appear to be an RDMA driver issue, do you know who we > should follow up with directly from the RDMA driver side of the world? > > Presumably non-brd devices, ie: real scsi devices work for these test > cases because they accept un-aligned buffers? Right, not every driver supports such un-aligned buffer. I am not familiar with RDMA, but from the trace we have done so far, it is highly related with iser driver. Thanks, Ming
