[    4.658071] input: Microsoft Natural\xffffffc2\xffffffae\xffffffae Ergonomic Keyboard 4000 as /devices/pci0000:00/0000:00:1d.7/usb2/2-2/2-2.1/2-2.1:1.0/input/input5
[    4.658266] microsoft 0003:045E:00DB.0001: input,hidraw0: USB HID v1.11 Keyboard [Microsoft Natural\xffffffc2\xffffffae\xffffffae Ergonomic Keyboard 4000] on usb-0000:00:1d.7-2.1/input0
[    4.669226] input: Microsoft Natural\xffffffc2\xffffffae\xffffffae Ergonomic Keyboard 4000 as /devices/pci0000:00/0000:00:1d.7/usb2/2-2/2-2.1/2-2.1:1.1/input/input6
[    4.669312] microsoft 0003:045E:00DB.0002: input,hidraw1: USB HID v1.11 Device [Microsoft Natural\xffffffc2\xffffffae\xffffffae Ergonomic Keyboard 4000] on usb-0000:00:1d.7-2.1/input1
[   31.699262] cfg80211: Found new beacon on frequency: 5745 MHz (Ch 149) on phy0
[   34.569563] vboxdrv: Found 2 processor cores.
[   34.569965] vboxdrv: fAsync=1 offMin=0x60b6f offMax=0x60b6f
[   34.570059] vboxdrv: TSC mode is 'asynchronous', kernel timer mode is 'normal'.
[   34.570061] vboxdrv: Successfully loaded version 4.1.12_Ubuntu (interface 0x00190000).
[   34.768403] vboxpci: IOMMU not found (not registered)
[   40.922241] init: plymouth-stop pre-start process (1912) terminated with status 1
[ 1935.808076] eth0: no IPv6 routers present
[261469.540566] sr 3:0:0:0: [sr0] Device not ready
[261469.540569] sr 3:0:0:0: [sr0]  Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[261469.540574] sr 3:0:0:0: [sr0]  Sense Key : Not Ready [current] 
[261469.540578] sr 3:0:0:0: [sr0]  Add. Sense: Medium not present
[261469.540584] sr 3:0:0:0: [sr0] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00
[261469.540593] end_request: I/O error, dev sr0, sector 0
[261469.540597] quiet_error: 24 callbacks suppressed
[261469.540599] Buffer I/O error on device sr0, logical block 0
[261469.540603] Buffer I/O error on device sr0, logical block 1
[261469.540605] Buffer I/O error on device sr0, logical block 2
[261469.540607] Buffer I/O error on device sr0, logical block 3
[261469.540610] Buffer I/O error on device sr0, logical block 4
[261469.540612] Buffer I/O error on device sr0, logical block 5
[261469.540614] Buffer I/O error on device sr0, logical block 6
[261469.540617] Buffer I/O error on device sr0, logical block 7
[261469.540620] Buffer I/O error on device sr0, logical block 8
[261469.540623] Buffer I/O error on device sr0, logical block 9
[261469.540663] sr 3:0:0:0: [sr0] unaligned transfer
[261469.540675] sr 3:0:0:0: [sr0] unaligned transfer
[261469.540683] sr 3:0:0:0: [sr0] unaligned transfer
[261469.540690] sr 3:0:0:0: [sr0] unaligned transfer
[261469.540707] sr 3:0:0:0: [sr0] unaligned transfer
[261469.540714] sr 3:0:0:0: [sr0] unaligned transfer
[261469.540721] sr 3:0:0:0: [sr0] unaligned transfer
[261469.540728] sr 3:0:0:0: [sr0] unaligned transfer
[268907.684955] do_general_protection: 22 callbacks suppressed
[268907.684965] chrome[2643] general protection ip:7f9c1e3acd30 sp:7fff63d72690 error:0 in chrome[7f9c1bcf2000+4c45000]