Comment 34 for bug 1366538

jkampe: I tried your workaround of adding usb-storage quirks 'uw' with my Maxtor OneTouch 250GB, same kernel as yours (3.16.0-31-generic #43~14.04.1-Ubuntu - x86_64). So far,

IT WORKS.

I'll have to test it further: I'm still running a (lengthy as in hours long) fsck caused by the previous test _without_ the quirks parameter ("filesystem with errors," etc.). But it does look good, I attached and detached the disk several times without the dreaded "end_request: critical target error, dev sdc, sector 0" that spelled trouble every time.

(In this case,
$ cat /etc/modprobe.d/maxtor-quirks.conf
options usb-storage quirks=0d49:7010:uw
)

I confirm the difference in dmesg, the line

(...) Write cache: enabled, read cache: enabled, doesn't support DPO or FUA

changes to

(...) Assuming drive cache: write through

-- As it should, I think, since this disk does not expose any caches/cache control to the kernel. But what do I know?

Relevant messages:

[ 1301.964044] usb 1-2: new high-speed USB device number 5 using ehci-pci
[ 1302.096937] usb 1-2: New USB device found, idVendor=0d49, idProduct=7010
[ 1302.096940] usb 1-2: New USB device strings: Mfr=1, Product=3, SerialNumber=2
[ 1302.096943] usb 1-2: Product: OneTouch
[ 1302.096945] usb 1-2: Manufacturer: Maxtor
[ 1302.096948] usb 1-2: SerialNumber: Y61JF0XE
[ 1302.117520] usbcore: registered new interface driver usb-storage
[ 1302.119336] usbcore: registered new interface driver uas
[ 1302.120923] ums-onetouch 1-2:1.0: USB Mass Storage device detected
[ 1302.121003] ums-onetouch 1-2:1.0: Quirks match for vid 0d49 pid 7010: 800200
[ 1302.121070] input: Maxtor OneTouch as /devices/pci0000:00/0000:00:1a.7/usb1/1-2/input/input13
[ 1302.121215] scsi9 : usb-storage 1-2:1.0
[ 1302.121303] usbcore: registered new interface driver ums-onetouch
[ 1303.326245] scsi 9:0:0:0: Direct-Access Maxtor OneTouch 0200 PQ: 0 ANSI: 0 CCS
[ 1303.326528] sd 9:0:0:0: Attached scsi generic sg3 type 0
[ 1303.327979] sd 9:0:0:0: [sdc] 490232832 512-byte logical blocks: (250 GB/233 GiB)
[ 1303.327984] sd 9:0:0:0: [sdc] Assuming Write Enabled
[ 1303.327987] sd 9:0:0:0: [sdc] Assuming drive cache: write through
[ 1303.362025] sdc: sdc1
[ 1303.363363] sd 9:0:0:0: [sdc] Attached SCSI disk

Thank you three times. This is some wizard level advice. :-) I never had heard about that "quirks" parameter... Let alone what might the value "uw" do.