On 10/09/19 09:00, Christoph Hellwig wrote:
On Tue, Oct 08, 2019 at 08:20:12PM +0000, bodo.stroesser@xxxxxxxxxxxxxx wrote:
1) Scan the SCSI specs and add all other missing command codes to the list of
Codes to skip
2) Create a list of commands that definitely have the LUN field in byte 1 and
reset the bits only in those. (Might be better than 1), because I expect new
commands to not have the LUN field.)
3) Remove the code entirely, because it is no longer needed / useful (?)
For 1) and 2) an additionally question is, based on what SCSI version the lists would
have to be created?
(4) limit the clearing of the LUN field to devices that claim
a compliance to SCSI-2 or earlier, as those use the LUN field.
I'm not sure that (4) would work.
The comment in the code says:
/*
* Clear a lun set in the cdb if the initiator talking to use spoke
* and old standards version, as we can't assume the underlying device
* won't choke up on it.
*/
If I understand correctly, the purpose of the code is just the opposite
from what you suggest, as it should reset useless LUN bits coming from
old (SCSI-2) initiators, that otherwise could confuse SCSI-3 or higher
targets.
SCSI-2 compliant targets should not run into trouble due to LUN bits
being set, I think.
