On Fri, Jul 20, 2018 at 04:03:18PM +0000, Bart Van Assche wrote:

On Fri, 2018-07-20 at 09:56 -0600, Keith Busch wrote:

quoted

SCSI is the only block driver that wants this behavior. Moving it back
to generic where it used to be breaks other block drivers.

That's new to me. What would break in the NVMe driver if the above change would be
present in the block layer?

This is what causes the block layer to lose completions, and most drivers
don't want the kernel to lose their completions.