On 4/11/23 16:23, Christoph Hellwig wrote: > On Tue, Apr 11, 2023 at 04:09:34PM +0900, Damien Le Moal wrote: >> But yes, I guess we could just unconditionally enable CDL for ATA on device scan >> to be on par with scsi, which has CDL always enabled. > > I'd prefer that. With a module option to not enable it just to be > safe. Thinking more about this, we cannot unconditionally enable CDL. The reason is that CDL and NCQ priority are mutually exclusive: if CDL is enabled, NCQ priority cannot be used. So with CDL unconditionally enabled, we cannot have NCQ priority enabled, preventing the user from choosing its preferred IO latency control method.
