[    0.000000] Initializing cgroup subsys cpuset
[    0.000000] Initializing cgroup subsys cpu
[    0.000000] Linux version 3.2.53-030253-generic (apw@gomeisa) (gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1
ubuntu5) ) #201311281435 SMP Thu Nov 28 19:36:21 UTC 2013
[    0.000000] Command line: BOOT_IMAGE=/vmlinuz-3.2.53-030253-generic root=/dev/mapper/ubuntu--vg-root ro
 recovery nomodeset
[    0.000000] KERNEL supported cpus:
...
[    1.175970] SCSI subsystem initialized
[    1.176000] libata version 3.00 loaded.
[    1.176033] usbcore: registered new interface driver usbfs
[    1.176043] usbcore: registered new interface driver hub
[    1.176061] usbcore: registered new device driver usb
[    2.047965] ahci 0000:00:1f.2: version 3.0
[    2.047976] ahci 0000:00:1f.2: PCI INT B -> GSI 19 (level, low) -> IRQ 19
[    2.048835] ahci 0000:00:1f.2: irq 45 for MSI/MSI-X
[    2.062968] ahci 0000:00:1f.2: AHCI 0001.0300 32 slots 6 ports 6 Gbps 0x5 impl SATA mode
[    2.063847] ahci 0000:00:1f.2: flags: 64bit ncq sntf pm led clo pio slum part ems apst 
[    2.064665] ahci 0000:00:1f.2: setting latency timer to 64
[    2.071412] scsi0 : ahci
[    2.072281] scsi1 : ahci
[    2.073122] scsi2 : ahci
[    2.073944] scsi3 : ahci
[    2.074745] scsi4 : ahci
[    2.075535] scsi5 : ahci
[    2.076425] ata1: SATA max UDMA/133 abar m2048@0xdff06000 port 0xdff06100 irq 45
[    2.077157] ata2: DUMMY
[    2.077871] ata3: SATA max UDMA/133 abar m2048@0xdff06000 port 0xdff06200 irq 45
[    2.078607] ata4: DUMMY
[    2.079339] ata5: DUMMY
[    2.080055] ata6: DUMMY
[    2.081032] Fixed MDIO Bus: probed
[    2.081743] tun: Universal TUN/TAP device driver, 1.6
[    2.082431] tun: (C) 1999-2004 Max Krasnyansky <email address hidden>
[    2.083154] PPP generic driver version 2.4.2
...
[    2.271428] rtc_cmos 00:06: setting system clock to 2013-12-24 15:50:13 UTC (1387900213)
[    2.273757] BIOS EDD facility v0.16 2004-Jun-25, 0 devices found
[    2.274368] EDD information not available.
[    2.398657] ata3: SATA link up 1.5 Gbps (SStatus 113 SControl 300)
[    2.399336] ata1: SATA link up 6.0 Gbps (SStatus 133 SControl 300)
[    2.400529] ata1.00: ACPI cmd f5/00:00:00:00:00:a0 (SECURITY FREEZE LOCK) filtered out
[    2.401154] ata1.00: ACPI cmd ef/10:06:00:00:00:a0 (SET FEATURES) succeeded
[    2.401206] ata1.00: ACPI cmd ef/90:03:00:00:00:a0 (SET FEATURES) succeeded
[    2.401527] ata1.00: supports DRM functions and may not be fully accessible
[    2.402229] ata1.00: ATA-9: Crucial_CT960M500SSD1, MU03, max UDMA/133
[    2.402871] ata1.00: 1875385008 sectors, multi 16: LBA48 NCQ (depth 31/32), AA
[    2.404074] ata1.00: ACPI cmd f5/00:00:00:00:00:a0 (SECURITY FREEZE LOCK) filtered out
[    2.404721] ata1.00: ACPI cmd ef/10:06:00:00:00:a0 (SET FEATURES) succeeded
[    2.404772] ata1.00: ACPI cmd ef/90:03:00:00:00:a0 (SET FEATURES) succeeded
[    2.405012] ata1.00: supports DRM functions and may not be fully accessible
[    2.405767] ata1.00: configured for UDMA/133
[    2.406557] scsi 0:0:0:0: Direct-Access     ATA      Crucial_CT960M50 MU03 PQ: 0 ANSI: 5
[    2.407392] sd 0:0:0:0: Attached scsi generic sg0 type 0
[    2.407427] sd 0:0:0:0: [sda] 1875385008 512-byte logical blocks: (960 GB/894 GiB)
[    2.407437] sd 0:0:0:0: [sda] 4096-byte physical blocks
[    2.407784] sd 0:0:0:0: [sda] Write Protect is off
[    2.407795] sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00
[    2.407904] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[    2.409888]  sda: sda1 sda2 sda3
[    2.411297] ata3.00: ACPI cmd ef/10:06:00:00:00:a0 (SET FEATURES) succeeded
[    2.412274] ata3.00: ACPI cmd ef/90:03:00:00:00:a0 (SET FEATURES) succeeded
[    2.412451] sd 0:0:0:0: [sda] Attached SCSI disk
[    2.415232] ata3.00: ATAPI: HL-DT-ST BDDVDRW CT30F, YT04, max UDMA/133
[    2.420305] ata3.00: ACPI cmd ef/10:06:00:00:00:a0 (SET FEATURES) succeeded
[    2.421301] ata3.00: ACPI cmd ef/90:03:00:00:00:a0 (SET FEATURES) succeeded
[    2.422606] usb 1-1: new high-speed USB device number 2 using ehci_hcd
[    2.424203] ata3.00: configured for UDMA/133
[    2.427691] scsi 2:0:0:0: CD-ROM            HL-DT-ST BDDVDRW CT30F    YT04 PQ: 0 ANSI: 5
[    2.432803] sr0: scsi3-mmc drive: 24x/24x writer dvd-ram cd/rw xa/form2 cdda tray
[    2.433555] cdrom: Uniform CD-ROM driver Revision: 3.20
[    2.434370] sr 2:0:0:0: Attached scsi CD-ROM sr0
[    2.434438] sr 2:0:0:0: Attached scsi generic sg1 type 5
[    2.436374] Freeing unused kernel memory: 924k freed
...
[ 6584.458441] EXT4-fs error (device dm-1): htree_dirblock_to_tree:587: inode #12849936: block 51389249: comm gvfsd-trash: bad entry in directory: directory entry across blocks - offset=0(12288), inode=2021400416, rec_len=26628, name_len=28
[ 6584.458450] Aborting journal on device dm-1-8.
[ 6584.458454] EXT4-fs (dm-1): ext4_da_writepages: jbd2_start: 1023 pages, ino 32779068; err -30
[ 6584.458902] EXT4-fs (dm-1): Remounting filesystem read-only
[ 6608.989429] show_signal_msg: 54 callbacks suppressed
[ 6608.989434] unity-scope-loa[6242]: segfault at 0 ip 00007f8bccc29cf0 sp 00007fff5da61ea8 error 4 in libc-2.18.so[7f8bccbb8000+1bc000]
[ 6611.000707] unity-scope-loa[6248]: segfault at 0 ip 00007ffdc7c58cf0 sp 00007fffe5bf8418 error 4 in libc-2.18.so[7ffdc7be7000+1bc000]



disabling discard fixes this for me on 3.2 and above kernel.  "rm" seems to trigger this bug . I have not yet been able to trigger this bug with discard disabled.