Yes, because it touches an actual ATA drive setting, while D_SENSE is
merely a "software setting" stored in dev->flags to make the kernel
response differently when build sense data.

On 26 July 2016 at 02:30, Tejun Heo [off-list ref] wrote:

On Fri, Jul 22, 2016 at 05:50:18AM +0800, Tom Yan wrote:

quoted

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().

But ata_mselect_caching() contructs a tf?

--
tejun