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Subject: Re: [PATCH] usb-storage: Add quirks to make G-Technology "G-Drive"
 work
To:     Oliver Neukum <oneukum@suse.com>,
        Alan Stern <stern@rowland.harvard.edu>
Cc:     gregkh@linuxfoundation.org, usb-storage@lists.one-eyed-alien.net,
        linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org
References: <Pine.LNX.4.44L0.1805161647330.1604-100000@iolanthe.rowland.org>
 <9c638d96-d2b4-cf19-d7e8-4ef93549bd79@godking.net>
 <1526561908.15506.5.camel@suse.com>
From:   Alexander Kappner <agk@godking.net>
Message-ID: <7dc7ea60-81b5-3546-5a12-9b0ff0b734cb@godking.net>
Date:   Thu, 17 May 2018 11:38:34 -0700
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Oliver and Alan,

thank for investigating.

> this is suspicious. You do not actually whether US_FL_NO_WP_DETECT
> by itself would make the device work. Can you please test that?

US_FL_NO_WP_DETECT without US_FL_IGNORE_UAS does not make a difference, 
even with the patch you included applied:

[   44.108417] JBD2: Clearing recovery information on journal
[   44.119593] sd 2:0:0:0: [sda] tag#1 FAILED Result: hostbyte=DID_OK 
driverbyte=DRIVER_SENSE
[   44.121605] sd 2:0:0:0: [sda] tag#1 Sense Key : Illegal Request 
[current] 
[   44.123254] sd 2:0:0:0: [sda] tag#1 Add. Sense: Invalid field in cdb
[   44.124798] sd 2:0:0:0: [sda] tag#1 CDB: Write(16) 8a 08 00 00 00 00 e8 
c4 00 00 00 00 00 08 00 00
[   44.126847] print_req_error: critical target error, dev sda, sector 
3905159168
[   44.128450] Buffer I/O error on dev sda, logical block 488144896, lost 
sync page write
[   44.130776] JBD2: Error -5 detected when updating journal superblock for 
sda-8.
[   44.141059] sd 2:0:0:0: [sda] tag#0 FAILED Result: hostbyte=DID_OK 
driverbyte=DRIVER_SENSE
[   44.141376] sd 2:0:0:0: [sda] tag#0 Sense Key : Illegal Request 
[current] 
[   44.141376] sd 2:0:0:0: [sda] tag#0 Add. Sense: Invalid field in cdb
[   44.141376] sd 2:0:0:0: [sda] tag#0 CDB: Write(16) 8a 08 00 00 00 00 00 
00 00 00 00 00 00 08 00 00
[   44.141376] print_req_error: critical target error, dev sda, sector 0
[   44.141376] Buffer I/O error on dev sda, logical block 0, lost sync page 
write

> That's bizarre too.  Even though the only difference is a MODE SENSE 
> command, the command that actually faliled was WRITE(16).
It looks to me like the MODE SENSE simply hangs the drive, so anything 
issued after that will fail. Of course the drive says it's the "current 
command" that caused the failure, but I wouldn't give too much credence to 
that. FYI -- this device is a consumer grade rotational drive that you can 
get for less than $200, so I wouldn't be surprised if the implementations 
have issues. 

Also, I noticed that copying onto the drive with dd works fine, whereas 
trying to mount a filesystem immediately crashes it. I suspect this is 
because check_disk_change is called on mount (which eventually calls down 
to sd_read_write_protect_flag, which is where the US_FL_NO_WP_DETECT flag 
comes into play).


On 05/17/2018 05:58 AM, Oliver Neukum wrote:
> Am Donnerstag, den 17.05.2018, 01:15 -0700 schrieb Alexander Kappner:
>> Yes. Without this flag, the device keeps throwing similar errors on 
>> usb-storage. That's the same result I get on a host that doesn't have UAS 
>> compiled in. Here's a dmesg:
> 
> Hi,
> 
> this is suspicious. You do not actually whether US_FL_NO_WP_DETECT
> by itself would make the device work. Can you please test that?
> You will need the attached patch for the quirk to be supported.
> 
> 	Regards
> 		Oliver
>