I've seen a few examples of USB storage devices that return clearly bogus error information on occasion. For instance, the device might return CHECK CONDITION status with SK=5 (Illegal request) and ASC=20 (Invalid command) for a WRITE_10, even though it has accepted many other READ_10 and WRITE_10 commands previously. I don't know why the device does this. When this happens, rather than failing the transfer entirely it makes sense to retry it. Right now sd will switch over from WRITE_10 to WRITE_6, which is definitely the wrong thing to do. I can prevent that easily enough. The question is how to force a retry. What information should sd_rw_intr() pass to scsi_io_completion() to request a retry? Or is there some other way of doing it? And how can the number of retries be limited, say to 3? Alan Stern - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
