On Thu, Jun 13, 2019 at 01:06:40PM -0400, Alan Stern wrote: > Hmmm. Would it be easier instead to copy the DMA mapping parameters > from us->pusb_dev->bus->sysdev into the SCSI host's parent before > calling scsi_add_host()? That way the correct values would be > available from the beginning, so the existing DMA setup would > automatically use the correct sizes. It would in theory. But at usb-storage has a special max_sectors quirk for tape devices, and as the device type is a per-LU property we'd still have to override it in ->slave_configure.