As I've mentioned in the comment/message, there is no ATA command needed to be sent to the device, since it only toggles a bit in dev->flags. See that there is no ata_taskfile constructed in ata_mselect_control(). On 22 July 2016 at 05:26, Tejun Heo <tj@xxxxxxxxxx> wrote: > On Fri, Jul 22, 2016 at 02:41:54AM +0800, tom.ty89@xxxxxxxxx wrote: >> @@ -3854,6 +3852,8 @@ static unsigned int ata_scsi_mode_select_xlat(struct ata_queued_cmd *qc) >> if (ata_mselect_control(qc, p, pg_len, &fp) < 0) { >> fp += hdr_len + bd_len; >> goto invalid_param; >> + } else { >> + goto skip; /* No ATA command to send */ > > Hmmm... I'm a bit confused. Why is mselect_control path different > from mselect_caching in terms of qc handling? > > Thanks. > > -- > tejun -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html