Hi, This follows on from something I mentioned in my recent post "[PATCH] storage: Don't scan target 7 for SCM USB-SCSI converters". In drivers/usb/storage/usb.c, usb_stor_control_thread(): /* reject if target != 0 or if LUN is higher than * the maximum known LUN */ else if (us->srb->device->id && !(us->fflags & US_FL_SCM_MULT_TARG)) { usb_stor_dbg(us, "Bad target number (%d:%llu)\n", us->srb->device->id, us->srb->device->lun); us->srb->result = DID_BAD_TARGET << 16; } else if (us->srb->device->lun > us->max_lun) { usb_stor_dbg(us, "Bad LUN (%d:%llu)\n", ... The condition (us->srb->device->id && !(us->fflags & US_FL_SCM_MULT_TARG)) means: - If not SCM_MULT_TARG, reject if us->srb->device->id is non-zero. That works for the usual case. - If SCM_MULT_TARG, never reject. Hmm... Would it be better/clearer to change the condition to simply (us->srb->device->id >= host->max_id) Then the command is rejected if us->srb->device->id is too large, and works for the SCM_MULT_TARG case too. (host->max_id is 1 for the non-SCM_MULT_TARG case.) Plus the condition matches nicely with the later LUN check. Untested patch below. Signed-off-by: Mark Knibbs <markk@xxxxxxxxxxx> diff -up linux-3.17-rc6/drivers/usb/storage/usb.c.orig linux-3.17-rc6/drivers/usb/storage/usb.c --- linux-3.17-rc6/drivers/usb/storage/usb.c.orig 2014-09-21 23:43:02.000000000 +0100 +++ linux-3.17-rc6/drivers/usb/storage/usb.c 2014-09-24 13:09:55.000000000 +0100 @@ -342,11 +342,10 @@ static int usb_stor_control_thread(void us->srb->result = DID_ERROR << 16; } - /* reject if target != 0 or if LUN is higher than + /* reject if target is invalid or if LUN is higher than * the maximum known LUN */ - else if (us->srb->device->id && - !(us->fflags & US_FL_SCM_MULT_TARG)) { + else if (us->srb->device->id >= host->max_id) { usb_stor_dbg(us, "Bad target number (%d:%llu)\n", us->srb->device->id, us->srb->device->lun); -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html