Here's the backtrace, I got it by tail -f'ing /var/log/messages while manually pm-suspending. Dec 23 22:38:23 skynet kernel: [ 99.592827] PM: Syncing filesystems ... done. Dec 23 22:38:23 skynet kernel: [ 99.595240] Freezing user space processes ... (elapsed 0.00 seconds) done. Dec 23 22:38:23 skynet kernel: [ 99.596063] Freezing remaining freezable tasks ... (elapsed 0.00 seconds) done. Dec 23 22:38:23 skynet kernel: [ 99.596125] Suspending console(s) (use no_console_suspend to debug) Dec 23 22:38:23 skynet kernel: [ 99.681303] sd 0:0:0:0: [sda] Synchronizing SCSI cache Dec 23 22:38:23 skynet kernel: [ 99.721164] sd 0:0:0:0: [sda] Stopping disk Dec 23 22:38:23 skynet kernel: [ 101.480144] ehci_hcd 0000:00:1d.7: PCI INT D disabled Dec 23 22:38:23 skynet kernel: [ 101.480153] uhci_hcd 0000:00:1d.2: PCI INT C disabled Dec 23 22:38:23 skynet kernel: [ 101.480161] uhci_hcd 0000:00:1d.1: PCI INT B disabled Dec 23 22:38:23 skynet kernel: [ 101.480168] uhci_hcd 0000:00:1d.0: PCI INT A disabled Dec 23 22:38:23 skynet kernel: [ 101.480173] pciehp 0000:00:1c.3:pcie04: pciehp_suspend ENTRY Dec 23 22:38:23 skynet kernel: [ 101.480177] pciehp 0000:00:1c.1:pcie04: pciehp_suspend ENTRY Dec 23 22:38:23 skynet kernel: [ 101.480181] pciehp 0000:00:1c.0:pcie04: pciehp_suspend ENTRY Dec 23 22:38:23 skynet kernel: [ 101.480207] HDA Intel 0000:00:1b.0: PCI INT B disabled Dec 23 22:38:23 skynet kernel: [ 101.500109] ehci_hcd 0000:00:1a.7: PCI INT D disabled Dec 23 22:38:23 skynet kernel: [ 101.500117] uhci_hcd 0000:00:1a.2: PCI INT C disabled Dec 23 22:38:23 skynet kernel: [ 101.500125] uhci_hcd 0000:00:1a.1: PCI INT B disabled Dec 23 22:38:23 skynet kernel: [ 101.500132] uhci_hcd 0000:00:1a.0: PCI INT A disabled Dec 23 22:38:23 skynet kernel: [ 101.500335] e1000e 0000:00:19.0: PCI INT A disabled Dec 23 22:38:23 skynet kernel: [ 101.500341] e1000e 0000:00:19.0: PME# enabled Dec 23 22:38:23 skynet kernel: [ 101.500346] e1000e 0000:00:19.0: wake-up capability enabled by ACPI Dec 23 22:38:23 skynet kernel: [ 101.540426] heci 0000:00:03.0: PCI INT A disabled Dec 23 22:38:23 skynet kernel: [ 101.611404] i915 0000:00:02.0: power state changed by ACPI to D3 Dec 23 22:38:23 skynet kernel: [ 101.611458] PM: suspend devices took 2.020 seconds Dec 23 22:38:23 skynet kernel: [ 101.611631] ehci_hcd 0000:00:1d.7: PME# disabled Dec 23 22:38:23 skynet kernel: [ 101.890057] ehci_hcd 0000:00:1d.7: power state changed by ACPI to D3 Dec 23 22:38:23 skynet kernel: [ 102.130065] uhci_hcd 0000:00:1d.0: power state changed by ACPI to D3 Dec 23 22:38:23 skynet kernel: [ 102.130267] ehci_hcd 0000:00:1a.7: PME# disabled Dec 23 22:38:23 skynet kernel: [ 102.390065] ehci_hcd 0000:00:1a.7: power state changed by ACPI to D3 Dec 23 22:38:23 skynet kernel: [ 102.630065] uhci_hcd 0000:00:1a.2: power state changed by ACPI to D3 Dec 23 22:38:23 skynet kernel: [ 102.870064] uhci_hcd 0000:00:1a.0: power state changed by ACPI to D3 Dec 23 22:38:23 skynet kernel: [ 103.230060] ACPI: Preparing to enter system sleep state S3 Dec 23 22:38:23 skynet kernel: [ 104.610195] Disabling non-boot CPUs ... Dec 23 22:38:23 skynet kernel: [ 104.720037] CPU 1 is now offline Dec 23 22:38:23 skynet kernel: [ 104.720040] SMP alternatives: switching to UP code Dec 23 22:38:23 skynet kernel: [ 104.727309] CPU1 is down Dec 23 22:38:23 skynet kernel: [ 104.727350] Extended CMOS year: 2000 Dec 23 22:38:23 skynet kernel: [ 104.727350] x86 PAT enabled: cpu 0, old 0x7040600070406, new 0x7010600070106 Dec 23 22:38:23 skynet kernel: [ 104.727350] Extended CMOS year: 2000 Dec 23 22:38:23 skynet kernel: [ 104.727350] Enabling non-boot CPUs ... Dec 23 22:38:23 skynet kernel: [ 104.727350] SMP alternatives: switching to SMP code Dec 23 22:38:23 skynet kernel: [ 104.734385] Booting processor 1 APIC 0x1 ip 0x6000 Dec 23 22:38:23 skynet kernel: [ 104.726953] Initializing CPU#1 Dec 23 22:38:23 skynet kernel: [ 104.726953] Calibrating delay using timer specific routine.. 3724.60 BogoMIPS (lpj=18623040) Dec 23 22:38:23 skynet kernel: [ 104.726953] CPU: L1 I cache: 32K, L1 D cache: 32K Dec 23 22:38:23 skynet kernel: [ 104.726953] CPU: L2 cache: 6144K Dec 23 22:38:23 skynet kernel: [ 104.726953] CPU 1/0x1 -> Node 0 Dec 23 22:38:23 skynet kernel: [ 104.726953] CPU: Physical Processor ID: 0 Dec 23 22:38:23 skynet kernel: [ 104.726953] CPU: Processor Core ID: 1 Dec 23 22:38:23 skynet kernel: [ 104.726953] mce: CPU supports 6 MCE banks Dec 23 22:38:23 skynet kernel: [ 104.726953] CPU1: Thermal monitoring enabled (TM2) Dec 23 22:38:23 skynet kernel: [ 104.726953] x86 PAT enabled: cpu 1, old 0x7040600070406, new 0x7010600070106 Dec 23 22:38:23 skynet kernel: [ 104.892822] CPU1: Intel(R) Core(TM)2 Duo CPU L9400 @ 1.86GHz stepping 0a Dec 23 22:38:23 skynet kernel: [ 104.931266] CPU1 is up Dec 23 22:38:23 skynet kernel: [ 104.931269] ACPI: Waking up from system sleep state S3 Dec 23 22:38:23 skynet kernel: [ 107.950059] uhci_hcd 0000:00:1a.0: power state changed by ACPI to D0 Dec 23 22:38:23 skynet kernel: [ 108.030065] uhci_hcd 0000:00:1a.2: power state changed by ACPI to D0 Dec 23 22:38:23 skynet kernel: [ 108.030162] ehci_hcd 0000:00:1a.7: PME# disabled Dec 23 22:38:23 skynet kernel: [ 108.110065] uhci_hcd 0000:00:1d.0: power state changed by ACPI to D0 Dec 23 22:38:23 skynet kernel: [ 108.110240] ehci_hcd 0000:00:1d.7: PME# disabled Dec 23 22:38:23 skynet kernel: [ 108.298757] [drm] LVDS-8: set mode 1440x900 c Dec 23 22:38:23 skynet kernel: [ 108.319064] pci 0000:00:02.1: PME# disabled Dec 23 22:38:23 skynet kernel: [ 108.319069] pci 0000:00:03.2: PME# disabled Dec 23 22:38:23 skynet kernel: [ 108.319094] e1000e 0000:00:19.0: PCI INT A -> GSI 20 (level, low) -> IRQ 20 Dec 23 22:38:23 skynet kernel: [ 108.319105] e1000e 0000:00:19.0: wake-up capability disabled by ACPI Dec 23 22:38:23 skynet kernel: [ 108.319110] e1000e 0000:00:19.0: PME# disabled Dec 23 22:38:23 skynet kernel: [ 108.319112] e1000e 0000:00:19.0: wake-up capability disabled by ACPI Dec 23 22:38:23 skynet kernel: [ 108.319117] e1000e 0000:00:19.0: PME# disabled Dec 23 22:38:23 skynet kernel: [ 108.383413] uhci_hcd 0000:00:1a.0: PCI INT A -> GSI 20 (level, low) -> IRQ 20 Dec 23 22:38:23 skynet kernel: [ 108.383442] usb usb3: root hub lost power or was reset Dec 23 22:38:23 skynet kernel: [ 108.383460] uhci_hcd 0000:00:1a.1: PCI INT B -> GSI 21 (level, low) -> IRQ 21 Dec 23 22:38:23 skynet kernel: [ 108.383488] usb usb4: root hub lost power or was reset Dec 23 22:38:23 skynet kernel: [ 108.383506] uhci_hcd 0000:00:1a.2: PCI INT C -> GSI 22 (level, low) -> IRQ 22 Dec 23 22:38:23 skynet kernel: [ 108.383535] usb usb5: root hub lost power or was reset Dec 23 22:38:23 skynet kernel: [ 108.383554] ehci_hcd 0000:00:1a.7: PME# disabled Dec 23 22:38:23 skynet kernel: [ 108.383557] ehci_hcd 0000:00:1a.7: PCI INT D -> GSI 23 (level, low) -> IRQ 23 Dec 23 22:38:23 skynet kernel: [ 108.383573] HDA Intel 0000:00:1b.0: PCI INT B -> GSI 17 (level, low) -> IRQ 17 Dec 23 22:38:23 skynet kernel: [ 108.383593] pciehp 0000:00:1c.0:pcie04: pciehp_resume ENTRY Dec 23 22:38:23 skynet kernel: [ 108.383597] pciehp 0000:00:1c.1:pcie04: pciehp_resume ENTRY Dec 23 22:38:23 skynet kernel: [ 108.383601] pciehp 0000:00:1c.3:pcie04: pciehp_resume ENTRY Dec 23 22:38:23 skynet kernel: [ 108.383606] uhci_hcd 0000:00:1d.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16 Dec 23 22:38:23 skynet kernel: [ 108.383635] usb usb6: root hub lost power or was reset Dec 23 22:38:23 skynet kernel: [ 108.383652] uhci_hcd 0000:00:1d.1: PCI INT B -> GSI 17 (level, low) -> IRQ 17 Dec 23 22:38:23 skynet kernel: [ 108.383680] usb usb7: root hub lost power or was reset Dec 23 22:38:23 skynet kernel: [ 108.383698] uhci_hcd 0000:00:1d.2: PCI INT C -> GSI 18 (level, low) -> IRQ 18 Dec 23 22:38:23 skynet kernel: [ 108.383727] usb usb8: root hub lost power or was reset Dec 23 22:38:23 skynet kernel: [ 108.383745] ehci_hcd 0000:00:1d.7: PME# disabled Dec 23 22:38:23 skynet kernel: [ 108.383749] ehci_hcd 0000:00:1d.7: PCI INT D -> GSI 19 (level, low) -> IRQ 19 Dec 23 22:38:23 skynet kernel: [ 108.730116] ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300) Dec 23 22:38:23 skynet kernel: [ 108.730146] ata2: SATA link down (SStatus 0 SControl 300) Dec 23 22:38:23 skynet kernel: [ 108.732343] ata1.00: ACPI cmd f5/00:00:00:00:00:a0 filtered out Dec 23 22:38:23 skynet kernel: [ 108.732347] ata1.00: ACPI cmd ef/10:03:00:00:00:a0 filtered out Dec 23 22:38:23 skynet kernel: [ 108.736962] ata1.00: ACPI cmd f5/00:00:00:00:00:a0 filtered out Dec 23 22:38:23 skynet kernel: [ 108.736965] ata1.00: ACPI cmd ef/10:03:00:00:00:a0 filtered out Dec 23 22:38:23 skynet kernel: [ 108.739005] ata1.00: configured for UDMA/133 Dec 23 22:38:23 skynet kernel: [ 108.741327] ata1: hard resetting link Dec 23 22:38:23 skynet kernel: [ 109.090064] ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300) Dec 23 22:38:23 skynet kernel: [ 109.092161] ata1.00: ACPI cmd f5/00:00:00:00:00:a0 filtered out Dec 23 22:38:23 skynet kernel: [ 109.092165] ata1.00: ACPI cmd ef/10:03:00:00:00:a0 filtered out Dec 23 22:38:23 skynet kernel: [ 109.096712] ata1.00: ACPI cmd f5/00:00:00:00:00:a0 filtered out Dec 23 22:38:23 skynet kernel: [ 109.096716] ata1.00: ACPI cmd ef/10:03:00:00:00:a0 filtered out Dec 23 22:38:23 skynet kernel: [ 109.098751] ata1.00: configured for UDMA/133 Dec 23 22:38:23 skynet kernel: [ 109.103207] ata1.00: configured for UDMA/133 Dec 23 22:38:23 skynet kernel: [ 109.103210] ata1: EH complete Dec 23 22:38:23 skynet kernel: [ 109.533050] sd 0:0:0:0: [sda] Starting disk Dec 23 22:38:23 skynet kernel: [ 109.670087] usb 2-3: reset high speed USB device using ehci_hcd and address 2 Dec 23 22:38:23 skynet kernel: [ 109.820597] i2400m_usb 2-3:1.0: no reset_resume for driver i2400m_usb? Dec 23 22:38:23 skynet kernel: [ 109.904106] i2400m_usb 2-3:1.0: firmware: requesting i2400m-fw-usb-1.4.sbcf Dec 23 22:38:23 skynet kernel: [ 169.900128] i2400m_usb 2-3:1.0: firmware: requesting i2400m-fw-usb-1.3.sbcf Dec 23 22:38:23 skynet kernel: [ 229.960129] i2400m_usb: probe of 2-3:1.0 failed with error -2 Dec 23 22:38:23 skynet kernel: [ 229.960295] PM: resume devices took 121.850 seconds Dec 23 22:38:23 skynet kernel: [ 229.960296] ------------[ cut here ]------------ Dec 23 22:38:23 skynet kernel: [ 229.960303] WARNING: at /build/buildd/linux-2.6.31/kernel/power/suspend_test.c:53 suspend_test_finish+0x82/0x90() Dec 23 22:38:23 skynet kernel: [ 229.960304] Hardware name: 7465CTO Dec 23 22:38:23 skynet kernel: [ 229.960306] Component: resume devices, time: 121850 Dec 23 22:38:23 skynet kernel: [ 229.960307] Modules linked in: cbc cryptd aes_x86_64 aes_generic binfmt_misc ppdev snd_hda_codec_conexant dm_crypt arc4 ecb i2400m_usb i2400m iwlagn iwlcore mac80211 snd_hda_intel snd_hda_codec snd_hwdep snd_pcm_oss snd_mixer_oss snd_pcm snd_seq_dummy iptable_filter snd_seq_oss snd_seq_midi wimax heci(C) cfg80211 psmouse serio_raw ip_tables x_tables snd_rawmidi thinkpad_acpi snd_seq_midi_event led_class nvram snd_seq snd_timer snd_seq_device snd soundcore snd_page_alloc lp parport fbcon tileblit font bitblit softcursor i915 drm i2c_algo_bit video output e1000e intel_agp Dec 23 22:38:23 skynet kernel: [ 229.960342] Pid: 2273, comm: pm-suspend Tainted: G C 2.6.31-16-generic #53-Ubuntu Dec 23 22:38:23 skynet kernel: [ 229.960344] Call Trace: Dec 23 22:38:23 skynet kernel: [ 229.960350] [] warn_slowpath_common+0x78/0xb0 Dec 23 22:38:23 skynet kernel: [ 229.960352] [] warn_slowpath_fmt+0x3c/0x40 Dec 23 22:38:23 skynet kernel: [ 229.960355] [] suspend_test_finish+0x82/0x90 Dec 23 22:38:23 skynet kernel: [ 229.960358] [] suspend_devices_and_enter+0xa9/0xe0 Dec 23 22:38:23 skynet kernel: [ 229.960361] [] enter_state+0xd8/0x110 Dec 23 22:38:23 skynet kernel: [ 229.960364] [] state_store+0x92/0x100 Dec 23 22:38:23 skynet kernel: [ 229.960367] [] kobj_attr_store+0x17/0x20 Dec 23 22:38:23 skynet kernel: [ 229.960372] [] sysfs_write_file+0xe0/0x160 Dec 23 22:38:23 skynet kernel: [ 229.960375] [] vfs_write+0xb8/0x1a0 Dec 23 22:38:23 skynet kernel: [ 229.960379] [] ? do_page_fault+0x194/0x370 Dec 23 22:38:23 skynet kernel: [ 229.960382] [] sys_write+0x4c/0x80 Dec 23 22:38:23 skynet kernel: [ 229.960386] [] system_call_fastpath+0x16/0x1b Dec 23 22:38:23 skynet kernel: [ 229.960388] ---[ end trace 38b933af4e5330f0 ]--- Dec 23 22:38:23 skynet kernel: [ 229.960420] Restarting tasks ... done. Dec 23 22:38:23 skynet firmware.sh[2533]: udev firmware loader misses sysfs directory Dec 23 22:38:23 skynet firmware.sh[2537]: udev firmware loader misses sysfs directory Dec 23 22:38:24 skynet kernel: [ 230.951432] ADDRCONF(NETDEV_UP): eth0: link is not ready Dec 23 22:38:26 skynet kernel: [ 232.691016] e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: RX/TX Dec 23 22:38:26 skynet kernel: [ 232.691025] 0000:00:19.0: eth0: 10/100 speed: disabling TSO Dec 23 22:38:26 skynet kernel: [ 232.692158] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready