Au niveau du dmesg ça donne cela :
[17609.031984] usb 1-2: USB disconnect, address 2
[19517.724019] usb 1-2: new high speed USB device using ehci_hcd and address 3
[19517.804033] hub 1-0:1.0: unable to enumerate USB device on port 2
[19518.164013] usb 1-2: new high speed USB device using ehci_hcd and address 4
[19518.297618] usb 1-2: New USB device found, idVendor=1058, idProduct=07a8
[19518.297620] usb 1-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[19518.297622] usb 1-2: Product: My Passport 07A8
[19518.297623] usb 1-2: Manufacturer: Western Digital
[19518.297624] usb 1-2: SerialNumber: 575837314139323531343535
[19518.297695] usb 1-2: configuration #1 chosen from 1 choice
[19518.297828] scsi7 : SCSI emulation for USB Mass Storage devices
[19518.297904] usb-storage: device found at 4
[19518.297905] usb-storage: waiting for device to settle before scanning
[19523.296123] usb-storage: device scan complete
[19523.410954] scsi 7:0:0:0: Direct-Access WD My Passport 07A8 1033 PQ: 0 ANSI: 6
[19523.411312] scsi 7:0:0:1: Enclosure WD SES Device 1033 PQ: 0 ANSI: 6
[19523.411575] sd 7:0:0:0: Attached scsi generic sg3 type 0
[19523.411619] ses 7:0:0:1: Attached Enclosure device
[19523.411648] ses 7:0:0:1: Attached scsi generic sg4 type 13
[19523.412940] sd 7:0:0:0: [sdc] 976707584 512-byte logical blocks: (500 GB/465 GiB)
[19523.414070] sd 7:0:0:0: [sdc] Write Protect is off
[19523.414073] sd 7:0:0:0: [sdc] Mode Sense: 53 00 10 08
[19523.414074] sd 7:0:0:0: [sdc] Assuming drive cache: write through
[19523.417319] sd 7:0:0:0: [sdc] Assuming drive cache: write through
[19523.417326] sdc: sdc1 sdc2 sdc3
[19523.444303] sd 7:0:0:0: [sdc] Assuming drive cache: write through
[19523.444310] sd 7:0:0:0: [sdc] Attached SCSI disk
[19523.446561] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
[19523.446572] IP: [<ffffffffa01585d5>] ses_enclosure_data_process+0x1c2/0x29c [ses]
[19523.446584] PGD 0
[19523.446589] Oops: 0002 [#1] SMP
[19523.446595] last sysfs file: /sys/devices/pci0000:00/0000:00:12.2/usb1/1-2/1-2:1.0/uevent
[19523.446603] CPU 1
[19523.446607] Modules linked in: ppdev lp tun nfsd lockd nfs_acl auth_rpcgss sunrpc exportfs ses enclosure reiserf
s ext3 jbd loop snd_hda_codec_atihdmi snd_hda_codec_via radeon ttm snd_hda_intel snd_hda_codec drm_kms_helper drm i
2c_algo_bit snd_hwdep snd_pcm snd_timer snd soundcore shpchp asus_atk0110 pci_hotplug parport_pc k10temp i2c_piix4
parport psmouse edac_core pcspkr serio_raw evdev i2c_core edac_mce_amd wmi snd_page_alloc button processor ext4 mbc
ache jbd2 crc16 dm_mod raid1 md_mod sg sr_mod cdrom sd_mod crc_t10dif r8169 ata_generic xhci usb_storage ohci_hcd e
hci_hcd mii pata_atiixp usbcore ahci nls_base libata thermal scsi_mod thermal_sys [last unloaded: scsi_wait_scan]
[19523.446716] Pid: 4425, comm: scsi_scan_7 Not tainted 2.6.32-5-amd64 #1 System Product Name
[19523.446724] RIP: 0010:[<ffffffffa01585d5>] [<ffffffffa01585d5>] ses_enclosure_data_process+0x1c2/0x29c [ses]
[19523.446734] RSP: 0018:ffff88011b349d20 EFLAGS: 00010282
[19523.446739] RAX: ffff88011bab6628 RBX: 0000000000000000 RCX: ffff88011bab6400
[19523.446745] RDX: ffff88011b9f9588 RSI: 0000000000000037 RDI: 0000000000000000
[19523.446750] RBP: ffff88011b9f9608 R08: ffffffff8149dd88 R09: ffff8800050557c0
[19523.446756] R10: 0000000000000001 R11: ffffffff810b6097 R12: ffff88011b2a79d8
[19523.446761] R13: 0000000000000001 R14: ffff88011b9f9594 R15: 0000000000002a1b
[19523.446767] FS: 00007f9607a877a0(0000) GS:ffff880005040000(0000) knlGS:0000000000000000
[19523.446774] CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b
[19523.446779] CR2: 0000000000000008 CR3: 0000000001001000 CR4: 00000000000006e0
[19523.446785] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[19523.446790] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[19523.446796] Process scsi_scan_7 (pid: 4425, threadinfo ffff88011b348000, task ffff88011c24f810)
[19523.446804] Stack:
[19523.446807] 0000000000000000 ffff88011b2a79dc ffff88011b9f9720 000000001ba03e42
[19523.446815] <0> ffff88011bab6400 0000000063ea9333 ffff88011b0fd820 ffff88011b08d500
[19523.446826] <0> ffff88011bab6400 ffff88011e5e7800 0000000000000010 ffff88011e5e2800
[19523.446839] Call Trace:
[19523.446845] [<ffffffffa01586f7>] ? ses_match_to_enclosure+0x48/0x140 [ses]
[19523.446851] [<ffffffffa0158b5c>] ? ses_intf_add+0x36d/0x447 [ses]
[19523.446859] [<ffffffff81220362>] ? device_add+0x41a/0x537
[19523.446866] [<ffffffff811407a7>] ? sysfs_add_file_mode+0x59/0x7f
[19523.446875] [<ffffffffa0013eb0>] ? scsi_sysfs_add_sdev+0xd5/0x1f4 [scsi_mod]
[19523.446884] [<ffffffffa00128b9>] ? do_scan_async+0x85/0x13a [scsi_mod]
[19523.446892] [<ffffffffa0012834>] ? do_scan_async+0x0/0x13a [scsi_mod]
[19523.446898] [<ffffffff81064ffd>] ? kthread+0x79/0x81
[19523.446904] [<ffffffff81011baa>] ? child_rip+0xa/0x20
[19523.446910] [<ffffffff810168ec>] ? read_tsc+0xa/0x20
[19523.446915] [<ffffffff81064f84>] ? kthread+0x0/0x81
[19523.446921] [<ffffffff81011ba0>] ? child_rip+0x0/0x20
[19523.446925] Code: 48 69 c0 28 02 00 00 48 8d 84 01 28 02 00 00 48 3d 00 f0 ff ff 0f 87 89 00 00 00 48 85 ed 0f 8
4 80 00 00 00 0f b6 75 00 48 8b 38 <48> 89 6f 08 40 84 f6 78 70 89 f0 31 c9 83 e0 0f 83 f8 06 75 61
[19523.447005] RIP [<ffffffffa01585d5>] ses_enclosure_data_process+0x1c2/0x29c [ses]
[19523.447014] RSP <ffff88011b349d20>
[19523.447018] CR2: 0000000000000008
[19523.447220] ---[ end trace d0fb96d4d1d90b28 ]---
[25000.221673] r8169 0000:03:00.0: eth0: link down
[25003.971087] r8169 0000:03:00.0: eth0: link up
[25020.175730] r8169 0000:03:00.0: eth0: link down
[25021.848010] r8169 0000:03:00.0: eth0: link up
[25095.016834] r8169 0000:03:00.0: eth0: link down
[25096.878661] r8169 0000:03:00.0: eth0: link up
[104462.669186] usb 1-2: USB disconnect, address 4
[151166.535642] sd 7:0:0:0: [sdc] Unhandled error code
[151166.535650] sd 7:0:0:0: [sdc] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[151166.535659] sd 7:0:0:0: [sdc] CDB: Read(10): 28 00 3a 37 50 8e 00 00 08 00
[151166.535678] end_request: I/O error, dev sdc, sector 976703630
[151166.535684] Buffer I/O error on device sdc3, logical block 972366080
[151166.535690] Buffer I/O error on device sdc3, logical block 972366081
[151166.535696] Buffer I/O error on device sdc3, logical block 972366082
[151166.535701] Buffer I/O error on device sdc3, logical block 972366083
[151166.535706] Buffer I/O error on device sdc3, logical block 972366084
[151166.535712] Buffer I/O error on device sdc3, logical block 972366085
[151166.535717] Buffer I/O error on device sdc3, logical block 972366086
[151166.535723] Buffer I/O error on device sdc3, logical block 972366087
[151166.535765] sd 7:0:0:0: [sdc] Unhandled error code
[151166.535773] sd 7:0:0:0: [sdc] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[151166.535782] sd 7:0:0:0: [sdc] CDB: Read(10): 28 00 3a 37 50 8e 00 00 08 00
[151166.535801] end_request: I/O error, dev sdc, sector 976703630
[151166.535807] Buffer I/O error on device sdc3, logical block 972366080
[151166.535813] Buffer I/O error on device sdc3, logical block 972366081
[151166.535868] sd 7:0:0:0: [sdc] Unhandled error code
[151166.535876] sd 7:0:0:0: [sdc] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[151166.535885] sd 7:0:0:0: [sdc] CDB: Read(10): 28 00 3a 37 51 26 00 00 08 00
[151166.535904] end_request: I/O error, dev sdc, sector 976703782
[151166.535924] sd 7:0:0:0: [sdc] Unhandled error code
[151166.535930] sd 7:0:0:0: [sdc] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[151166.535938] sd 7:0:0:0: [sdc] CDB: Read(10): 28 00 3a 37 51 26 00 00 08 00
[151166.535956] end_request: I/O error, dev sdc, sector 976703782
[151166.535977] sd 7:0:0:0: [sdc] Unhandled error code
[151166.535982] sd 7:0:0:0: [sdc] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[151166.535991] sd 7:0:0:0: [sdc] CDB: Read(10): 28 00 00 42 2f 8e 00 00 08 00
[151166.536009] end_request: I/O error, dev sdc, sector 4337550
[151166.536054] sd 7:0:0:0: [sdc] Unhandled error code
[151166.536063] sd 7:0:0:0: [sdc] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[151166.536071] sd 7:0:0:0: [sdc] CDB: Read(10): 28 00 00 42 2f 8e 00 00 08 00
[151166.536091] end_request: I/O error, dev sdc, sector 4337550
[151166.536115] sd 7:0:0:0: [sdc] Unhandled error code
[151166.536121] sd 7:0:0:0: [sdc] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[151166.536130] sd 7:0:0:0: [sdc] CDB: Read(10): 28 00 00 42 2f 96 00 00 08 00
[151166.536154] end_request: I/O error, dev sdc, sector 4337558
[151166.537632] sd 7:0:0:0: [sdc] Unhandled error code
[151166.537640] sd 7:0:0:0: [sdc] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[151166.537648] sd 7:0:0:0: [sdc] CDB: Read(10): 28 00 3a 37 51 36 00 00 07 00
[151166.537666] end_request: I/O error, dev sdc, sector 976703798
[151166.537700] sd 7:0:0:0: [sdc] Unhandled error code
[151166.537707] sd 7:0:0:0: [sdc] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[151166.537715] sd 7:0:0:0: [sdc] CDB: Read(10): 28 00 3a 37 51 36 00 00 07 00
[151166.537734] end_request: I/O error, dev sdc, sector 976703798
[151166.537754] sd 7:0:0:0: [sdc] Unhandled error code
[151166.537759] sd 7:0:0:0: [sdc] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[151166.537767] sd 7:0:0:0: [sdc] CDB: Read(10): 28 00 3a 37 51 36 00 00 07 00
[151166.537786] end_request: I/O error, dev sdc, sector 976703798
[151166.537805] sd 7:0:0:0: [sdc] Unhandled error code
[151166.537810] sd 7:0:0:0: [sdc] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[151166.537818] sd 7:0:0:0: [sdc] CDB: Read(10): 28 00 3a 37 51 36 00 00 07 00
[151166.537837] end_request: I/O error, dev sdc, sector 976703798
[151166.537856] sd 7:0:0:0: [sdc] Unhandled error code
[151166.537861] sd 7:0:0:0: [sdc] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[151166.537869] sd 7:0:0:0: [sdc] CDB: Read(10): 28 00 3a 37 51 36 00 00 07 00
[151166.537888] end_request: I/O error, dev sdc, sector 976703798
[151166.537908] sd 7:0:0:0: [sdc] Unhandled error code
[151166.537913] sd 7:0:0:0: [sdc] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
[151166.537921] sd 7:0:0:0: [sdc] CDB: Read(10): 28 00 3a 37 51 36 00 00 07 00
[151166.537939] end_request: I/O error, dev sdc, sector 976703798
[151166.537959] sd 7:0:0:0: [sdc] Unhandled error code