Unfortunately the test kernel does not fix the bug, see:

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[   89.544267] usb 4-3: USB disconnect, device number 2
[   89.544898] sd 6:0:0:0: [sdb] Synchronizing SCSI cache
[   89.544956] sd 6:0:0:0: [sdb]  
[   89.544958] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[   89.545052] usb 4-3: Set SEL for device-initiated U1 failed.
[   89.545053] usb 4-3: Set SEL for device-initiated U2 failed.
[   92.965861] usb 4-3: new SuperSpeed USB device number 3 using xhci_hcd
[   92.977711] usb 4-3: New USB device found, idVendor=174c, idProduct=55aa
[   92.977716] usb 4-3: New USB device strings: Mfr=2, Product=3, SerialNumber=1
[   92.977729] usb 4-3: Product: USB 3.0 Device
[   92.977731] usb 4-3: Manufacturer: Intenso
[   92.977733] usb 4-3: SerialNumber: 31800000000000003E38
[   92.978349] usb-storage 4-3:1.0: USB Mass Storage device detected
[   92.978435] usb-storage 4-3:1.0: Quirks match for vid 174c pid 55aa: 400000
[   92.978481] scsi9 : usb-storage 4-3:1.0
[   93.981618] scsi 9:0:0:0: Direct-Access     Intenso  USB 3.0 Device   0    PQ: 0 ANSI: 6
[   93.981793] sd 9:0:0:0: Attached scsi generic sg2 type 0
[   95.233545] sd 9:0:0:0: [sdb] 1953525168 512-byte logical blocks: (1.00 TB/931 GiB)
[   95.233548] sd 9:0:0:0: [sdb] 4096-byte physical blocks
[   95.233853] sd 9:0:0:0: [sdb] Write Protect is off
[   95.233857] sd 9:0:0:0: [sdb] Mode Sense: 43 00 00 00
[   95.234134] sd 9:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[   95.247774]  sdb: sdb1 sdb2 sdb3
[   95.249078] sd 9:0:0:0: [sdb] Attached SCSI disk
[  295.886411] usb 4-3: USB disconnect, device number 3
[  295.886939] sd 9:0:0:0: [sdb] Synchronizing SCSI cache
[  295.887031] sd 9:0:0:0: [sdb]  
[  295.887034] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[  295.887138] usb 4-3: Set SEL for device-initiated U1 failed.
[  295.887140] usb 4-3: Set SEL for device-initiated U2 failed.
[  296.092510] usb 4-3: new SuperSpeed USB device number 4 using xhci_hcd
[  296.103979] usb 4-3: New USB device found, idVendor=174c, idProduct=55aa
[  296.103981] usb 4-3: New USB device strings: Mfr=2, Product=3, SerialNumber=1
[  296.103983] usb 4-3: Product: USB 3.0 Device
[  296.103984] usb 4-3: Manufacturer: Intenso
[  296.103986] usb 4-3: SerialNumber: 31800000000000003E38
[  296.104600] usb-storage 4-3:1.0: USB Mass Storage device detected
[  296.104652] usb-storage 4-3:1.0: Quirks match for vid 174c pid 55aa: 400000
[  296.104680] scsi10 : usb-storage 4-3:1.0
[  297.107297] scsi 10:0:0:0: Direct-Access     Intenso  USB 3.0 Device   0    PQ: 0 ANSI: 6
[  297.107654] sd 10:0:0:0: [sdb] 1953525168 512-byte logical blocks: (1.00 TB/931 GiB)
[  297.107656] sd 10:0:0:0: [sdb] 4096-byte physical blocks
[  297.107786] sd 10:0:0:0: Attached scsi generic sg2 type 0
[  297.107917] sd 10:0:0:0: [sdb] Write Protect is off
[  297.107928] sd 10:0:0:0: [sdb] Mode Sense: 43 00 00 00
[  297.108172] sd 10:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[  297.109296]  sdb: sdb1 sdb2 sdb3
[  297.110307] sd 10:0:0:0: [sdb] Attached SCSI disk
st-brauchle:/home/brauchle # uname -a
Linux st-brauchle 3.11.10-1.g17fc0f0-desktop #1 SMP PREEMPT Thu Mar 13 09:14:49 UTC 2014 (17fc0f0) x86_64 x86_64 x86_64 GNU/Linux
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