Re: [PATCH] Recognize missing LUNs for non-standard devices

[Brian King <brking@us.ibm.com>]

Alan Stern wrote:
> On Mon, 6 Feb 2006, Brian King wrote:
> 
>> Alan Stern wrote:
>>> Some protocols (like USB UFI) or devices that don't adhere to the SCSI
>>> standard may indicate a nonexistent LUN by returning INQUIRY information
>>> with Peripheral Device Type set to 0x1f (unknown or none) and Peripheral
>>> Qualifier set to 0 instead of 3 as the spec requires.  This patch (as650)
>>> causes PDT = 0x1f to be recognized as no LUN present regardless of the
>>> qualifier value, if the SCSI level is equal to 0.
>> This patch will break the ipr driver. The ipr adapter firmware reports a
>> logical scsi device which is used for RAID configuration. It reports
>> a Peripheral Device Type of 0x1f and a scsi level of 0, since it does
>> not claim compliance with any scsi level. 
> 
> I was afraid that might happen.  Okay, forget the patch.
> 
> How come you didn't mention the ipr driver before when I first raised the 
> possibility of making this change?

Sorry about that... I wanted to verify on my end that the scsi level getting
returned was 0 before doing so. Your repost was a reminder...

Brian

-- 
Brian King
eServer Storage I/O
IBM Linux Technology Center