On Mon, 2017-12-04 at 15:20 +0000, Bean Huo (beanhuo) wrote: > Also, is it possible bypass SCSI stacks and go into directly UFS stack? Hello Bean, Sorry but I think it would be wrong to bypass the block layer when submitting UFS commands. My understanding is that UFS devices are used in systems where power management functionality is important (see also Documentation/power). If the block layer would be bypassed then the power management support that exists in the block layer will have to be reimplemented in UFS devices. That would be a duplicate effort. I'm not sure that we want such duplication. Bart.