Parece que você está enfrentando esse bug .
Olhando para a descrição do erro, eu acho que uma possível solução é voltar a portar o kernel para a versão 2.6.35.
Meu drive USB externo foi reconhecido com as versões 10.x do Ubuntu, mas desde 11.x estou ficando preso, tentei tudo o que li nos fóruns, mas ainda o mesmo erro:
4956.401052] usb 2-1.4: new high speed USB device number 14 using ehci_hcd
[ 4956.539216] scsi14 : uas
[ 4956.740955] scsi 14:0:0:0: Direct-Access LaCie Rugged FW USB3 1081 PQ: 0 ANSI: 4
[ 4963.256055] scsi 14:0:0:0: uas_eh_abort_handler tag 0
[ 4963.256076] scsi 14:0:0:0: uas_eh_device_reset_handler tag 0
[ 4963.256085] scsi 14:0:0:0: uas_eh_target_reset_handler tag 0
[ 4963.256091] scsi 14:0:0:0: uas_eh_bus_reset_handler tag 0
[ 4963.328122] usb 2-1.4: reset high speed USB device number 14 using ehci_hcd
[ 4963.468743] scsi 14:0:0:0: Device offlined - not ready after error recovery
[ 4963.468813] scsi 14:0:0:0: rejecting I/O to offline device
[ 4963.468831] scsi 14:0:0:0: rejecting I/O to offline device
[ 4963.469204] scsi 14:0:0:1: uas_sense_old: urb length 26 disagrees with IU sense data length 510, using 18 bytes of sense data
[ 4963.512104] sd 14:0:0:0: Attached scsi generic sg3 type 0
[ 4994.253779] sd 14:0:0:0: uas_eh_abort_handler tag 0
[ 4994.253802] sd 14:0:0:0: uas_eh_device_reset_handler tag 0
[ 4994.253809] sd 14:0:0:0: uas_eh_target_reset_handler tag 0
[ 4994.253815] sd 14:0:0:0: uas_eh_bus_reset_handler tag 0
[ 4994.325880] usb 2-1.4: reset high speed USB device number 14 using ehci_hcd
[ 4994.466488] sd 14:0:0:0: Device offlined - not ready after error recovery
[ 4994.466555] sd 14:0:0:0: rejecting I/O to offline device
[ 4994.466573] sd 14:0:0:0: rejecting I/O to offline device
[ 4994.466582] sd 14:0:0:0: rejecting I/O to offline device
[ 4994.466588] sd 14:0:0:0: [sdc] READ CAPACITY failed
[ 4994.466593] sd 14:0:0:0: [sdc] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[ 4994.466600] sd 14:0:0:0: [sdc] Sense not available.
[ 4994.466608] sd 14:0:0:0: rejecting I/O to offline device
[ 4994.466616] sd 14:0:0:0: [sdc] Write Protect is off
[ 4994.466622] sd 14:0:0:0: [sdc] Mode Sense: 00 00 00 00
[ 4994.466629] sd 14:0:0:0: rejecting I/O to offline device
[ 4994.466635] sd 14:0:0:0: [sdc] Asking for cache data failed
[ 4994.466640] sd 14:0:0:0: [sdc] Assuming drive cache: write through
[ 4994.467003] sd 14:0:0:0: [sdc] Attached SCSI disk
se eu estou tentando em um velho Ubuntu, a unidade está montada,