This is a Lenovo T61p w/4GB RAM.

Yesterday, the following was logged after I was trying to maximise a window in Firefox (Compiz was running). The system froze, but not hard -- drive light etc was flashing after the GUI froze:

Nov  3 20:36:10 t61p kernel: [26887.549569] ------------[ cut here ]------------
Nov  3 20:36:10 t61p kernel: [26887.549573] WARNING: at /build/buildd/linux-2.6.28/kernel/futex.c:587 lookup_pi_state+0x24f/0x2a0()
Nov  3 20:36:10 t61p kernel: [26887.549576] Modules linked in: usb_storage ppp_deflate zlib_deflate bsd_comp ppp_async crc_ccitt binfmt_misc bridge stp bnep vboxnetadp vboxnetflt vboxdrv vmnet ppdev parport_pc vmblock vsock vmci vmmon input_polldev lp parport snd_hda_intel joydev snd_pcm_oss snd_mixer_oss snd_pcm snd_seq_dummy snd_seq_oss snd_seq_midi snd_rawmidi arc4 snd_seq_midi_event ecb snd_seq pcmcia snd_timer snd_seq_device iwlagn thinkpad_acpi iwlcore iTCO_wdt yenta_socket video sierra mac80211 led_class psmouse snd rsrc_nonstatic pcmcia_core iTCO_vendor_support output usbserial intel_agp btusb nvram serio_raw pcspkr sdhci_pci sdhci ricoh_mmc cfg80211 soundcore snd_page_alloc nvidia(P) usbhid ohci1394 ieee1394 e1000e fbcon tileblit font bitblit softcursor
Nov  3 20:36:10 t61p kernel: [26887.549642] Pid: 18242, comm: totem Tainted: P        W  2.6.28-16-generic #55-Ubuntu
Nov  3 20:36:10 t61p kernel: [26887.549645] Call Trace:
Nov  3 20:36:10 t61p kernel: [26887.549651]  [<ffffffff80250b7f>] warn_on_slowpath+0x5f/0x90
Nov  3 20:36:10 t61p kernel: [26887.549656]  [<ffffffff802c00be>] ? __dec_zone_page_state+0x1e/0x20
Nov  3 20:36:10 t61p kernel: [26887.549661]  [<ffffffff802ce900>] ? page_remove_rmap+0x60/0x150
Nov  3 20:36:10 t61p kernel: [26887.549664]  [<ffffffff802c30bd>] ? zap_pte_range+0x2cd/0x420
Nov  3 20:36:10 t61p kernel: [26887.549669]  [<ffffffff80265731>] ? find_task_by_pid_type_ns+0x11/0x50
Nov  3 20:36:10 t61p kernel: [26887.549672]  [<ffffffff8027719f>] lookup_pi_state+0x24f/0x2a0
Nov  3 20:36:10 t61p kernel: [26887.549675]  [<ffffffff80278974>] futex_lock_pi+0x294/0x6b0
Nov  3 20:36:10 t61p kernel: [26887.549679]  [<ffffffff802c4d60>] ? zap_page_range+0x100/0x110
Nov  3 20:36:10 t61p kernel: [26887.549682]  [<ffffffff802c1ed5>] ? madvise_vma+0xf5/0x380
Nov  3 20:36:10 t61p kernel: [26887.549685]  [<ffffffff80278e5c>] do_futex+0xcc/0x140
Nov  3 20:36:10 t61p kernel: [26887.549688]  [<ffffffff80278f96>] sys_futex+0xc6/0x170
Nov  3 20:36:10 t61p kernel: [26887.549692]  [<ffffffff8026ceb9>] ? up_read+0x9/0x10
Nov  3 20:36:10 t61p kernel: [26887.549695]  [<ffffffff802c2211>] ? sys_madvise+0xb1/0x270
Nov  3 20:36:10 t61p kernel: [26887.549700]  [<ffffffff8021253a>] system_call_fastpath+0x16/0x1b
Nov  3 20:36:10 t61p kernel: [26887.549702] ---[ end trace 22b3865163e92338 ]---
Nov  3 20:36:17 t61p kernel: [26894.178627] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
Nov  3 20:36:17 t61p kernel: [26894.178635] IP: [<ffffffffa033b671>] _nv004881rm+0x75/0x89 [nvidia]
Nov  3 20:36:17 t61p kernel: [26894.178895] PGD 130ca7067 PUD 130d18067 PMD 0 
Nov  3 20:36:17 t61p kernel: [26894.178901] Oops: 0000 [#1] SMP 
Nov  3 20:36:17 t61p kernel: [26894.178905] last sysfs file: /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
Nov  3 20:36:17 t61p kernel: [26894.178910] Dumping ftrace buffer:
Nov  3 20:36:17 t61p kernel: [26894.178914]    (ftrace buffer empty)
Nov  3 20:36:17 t61p kernel: [26894.178916] CPU 1 
Nov  3 20:36:17 t61p kernel: [26894.178919] Modules linked in: usb_storage ppp_deflate zlib_deflate bsd_comp ppp_async crc_ccitt binfmt_misc bridge stp bnep vboxnetadp vboxnetflt vboxdrv vmnet ppdev parport_pc vmblock vsock vmci vmmon input_polldev lp parport snd_hda_intel joydev snd_pcm_oss snd_mixer_oss snd_pcm snd_seq_dummy snd_seq_oss snd_seq_midi snd_rawmidi arc4 snd_seq_midi_event ecb snd_seq pcmcia snd_timer snd_seq_device iwlagn thinkpad_acpi iwlcore iTCO_wdt yenta_socket video sierra mac80211 led_class psmouse snd rsrc_nonstatic pcmcia_core iTCO_vendor_support output usbserial intel_agp btusb nvram serio_raw pcspkr sdhci_pci sdhci ricoh_mmc cfg80211 soundcore snd_page_alloc nvidia(P) usbhid ohci1394 ieee1394 e1000e fbcon tileblit font bitblit softcursor
Nov  3 20:36:17 t61p kernel: [26894.178997] Pid: 3511, comm: Xorg Tainted: P        W  2.6.28-16-generic #55-Ubuntu
Nov  3 20:36:17 t61p kernel: [26894.179000] RIP: 0010:[<ffffffffa033b671>]  [<ffffffffa033b671>] _nv004881rm+0x75/0x89 [nvidia]
Nov  3 20:36:17 t61p kernel: [26894.179223] RSP: 0018:ffff88013a993cf0  EFLAGS: 00010286
Nov  3 20:36:17 t61p kernel: [26894.179226] RAX: 0000000000000000 RBX: ffff88013a916f30 RCX: 0000000004597000
Nov  3 20:36:17 t61p kernel: [26894.179229] RDX: 000000000000f0f0 RSI: ffff88013a11b800 RDI: 0000000000000000
Nov  3 20:36:17 t61p kernel: [26894.179232] RBP: ffff88013a916f28 R08: ffff88013a916f30 R09: ffff88013a916f38
Nov  3 20:36:17 t61p kernel: [26894.179235] R10: 00007f2d57783ca8 R11: 0000000000003246 R12: ffff88013a916f38
Nov  3 20:36:17 t61p kernel: [26894.179238] R13: ffff88013a11b800 R14: ffff88013898a000 R15: ffff88013a916f3c
Nov  3 20:36:17 t61p kernel: [26894.179242] FS:  00007f2d5ca95700(0000) GS:ffff88013b803c80(0000) knlGS:0000000000000000
Nov  3 20:36:17 t61p kernel: [26894.179245] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
Nov  3 20:36:17 t61p kernel: [26894.179248] CR2: 0000000000000018 CR3: 0000000139968000 CR4: 00000000000006a0
Nov  3 20:36:17 t61p kernel: [26894.179252] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
Nov  3 20:36:17 t61p kernel: [26894.179255] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Nov  3 20:36:17 t61p kernel: [26894.179258] Process Xorg (pid: 3511, threadinfo ffff88013a992000, task ffff880139d30000)
Nov  3 20:36:17 t61p kernel: [26894.179261] Stack:
Nov  3 20:36:17 t61p kernel: [26894.179263]  ffffffffa033b4a3 00000000c1d00001 ffff88013898a000 0000000000000000
Nov  3 20:36:17 t61p kernel: [26894.179269]  00000000cafe0ab9 0000000080010000 ffffffffa038f8bb ffff88013a916f3c
Nov  3 20:36:17 t61p kernel: [26894.179276]  ffffffffa038f86c 0000000000000040 00000000c1d00001 0000000080010000
Nov  3 20:36:17 t61p kernel: [26894.179283] Call Trace:
Nov  3 20:36:17 t61p kernel: [26894.179287]  [<ffffffffa033b4a3>] ? _nv004880rm+0x26/0x80 [nvidia]
Nov  3 20:36:17 t61p kernel: [26894.179509]  [<ffffffffa038f8bb>] ? _nv003230rm+0xc6/0xde [nvidia]
Nov  3 20:36:17 t61p kernel: [26894.179721]  [<ffffffffa038f86c>] ? _nv003230rm+0x77/0xde [nvidia]
Nov  3 20:36:17 t61p kernel: [26894.179933]  [<ffffffffa038f7ad>] ? _nv003226rm+0x202/0x24a [nvidia]
Nov  3 20:36:17 t61p kernel: [26894.180145]  [<ffffffffa038db67>] ? _nv003245rm+0x17a/0x2f8 [nvidia]
Nov  3 20:36:17 t61p kernel: [26894.180357]  [<ffffffffa0388f67>] ? _nv006021rm+0x72/0x9f [nvidia]
Nov  3 20:36:17 t61p kernel: [26894.180572]  [<ffffffffa0209105>] ? _nv003189rm+0x1e5/0x6fd [nvidia]
Nov  3 20:36:17 t61p kernel: [26894.180770]  [<ffffffffa040845d>] ? rm_ioctl+0x2f/0x67 [nvidia]
Nov  3 20:36:17 t61p kernel: [26894.180986]  [<ffffffffa04c5db3>] ? nv_kern_ioctl+0x1b3/0x480 [nvidia]
Nov  3 20:36:17 t61p kernel: [26894.181009]  [<ffffffffa04c60bc>] ? nv_kern_unlocked_ioctl+0x1c/0x20 [nvidia]
Nov  3 20:36:17 t61p kernel: [26894.181009]  [<ffffffff802f65f1>] ? vfs_ioctl+0x31/0xa0
Nov  3 20:36:17 t61p kernel: [26894.181009]  [<ffffffff802f69a5>] ? do_vfs_ioctl+0x75/0x230
Nov  3 20:36:17 t61p kernel: [26894.181009]  [<ffffffff802f6bf9>] ? sys_ioctl+0x99/0xa0
Nov  3 20:36:17 t61p kernel: [26894.181009]  [<ffffffff8026cea9>] ? up_write+0x9/0x10
Nov  3 20:36:17 t61p kernel: [26894.181009]  [<ffffffff8021253a>] ? system_call_fastpath+0x16/0x1b
Nov  3 20:36:17 t61p kernel: [26894.181009] Code: 37 48 89 f8 eb 37 48 89 f8 90 eb 31 48 8b 47 18 48 03 47 20 48 39 c8 75 05 39 57 04 74 e8 48 8b 7f 78 48 39 be f0 01 00 00 74 0d <48> 8b 47 18 48 03 47 20 48 39 c8 76 d4 b8 00 00 00 00 f3 c3 41 
Nov  3 20:36:17 t61p kernel: [26894.181009] RIP  [<ffffffffa033b671>] _nv004881rm+0x75/0x89 [nvidia]
Nov  3 20:36:17 t61p kernel: [26894.181009]  RSP <ffff88013a993cf0>
Nov  3 20:36:17 t61p kernel: [26894.181009] CR2: 0000000000000018
Nov  3 20:36:17 t61p kernel: [26894.181673] ---[ end trace 22b3865163e92338 ]---
Nov  3 20:37:52 t61p kernel: [26989.013181] usb 2-2: USB disconnect, address 5
Nov  3 20:38:04 t61p dhclient: DHCPREQUEST of 192.168.5.174 on wlan0 to 192.168.5.254 port 67
Nov  3 20:38:04 t61p dhclient: DHCPACK of 192.168.5.174 from 192.168.5.254
Nov  3 20:38:04 t61p dhclient: bound to 192.168.5.174 -- renewal in 495 seconds.
Nov  3 20:39:42 t61p syslogd 1.5.0#5ubuntu3: restart.
Nov  3 20:39:42 t61p kernel: Inspecting /boot/System.map-2.6.28-16-generic

Later, after rebooting, I was editing in Eclipse -- the same thing happened, the GUI froze, but there appeared to be drive activity. This was logged:

Nov  3 22:53:38 t61p kernel: [ 8066.258512] ------------[ cut here ]------------
Nov  3 22:53:38 t61p kernel: [ 8066.258524] kernel BUG at /build/buildd/linux-2.6.28/mm/slub.c:2743!
Nov  3 22:53:38 t61p kernel: [ 8066.258530] invalid opcode: 0000 [#1] SMP 
Nov  3 22:53:38 t61p kernel: [ 8066.258537] last sysfs file: /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
Nov  3 22:53:38 t61p kernel: [ 8066.258543] Dumping ftrace buffer:
Nov  3 22:53:38 t61p kernel: [ 8066.258548]    (ftrace buffer empty)
Nov  3 22:53:38 t61p kernel: [ 8066.258552] CPU 0 
Nov  3 22:53:38 t61p kernel: [ 8066.258556] Modules linked in: usb_storage binfmt_misc bridge stp bnep vboxnetadp vboxnetflt vboxdrv vmnet ppdev parport_pc vmblock vsock vmci vmmon input_polldev lp parport snd_hda_intel snd_pcm_oss snd_mixer_oss joydev snd_pcm snd_seq_dummy snd_seq_oss arc4 snd_seq_midi snd_rawmidi ecb snd_seq_midi_event pcmcia snd_seq iwlagn iwlcore snd_timer snd_seq_device yenta_socket thinkpad_acpi mac80211 snd video rsrc_nonstatic led_class psmouse soundcore intel_agp pcmcia_core iTCO_wdt iTCO_vendor_support output sierra usbserial nvram btusb pcspkr ricoh_mmc sdhci_pci sdhci serio_raw cfg80211 snd_page_alloc nvidia(P) usbhid ohci1394 ieee1394 e1000e fbcon tileblit font bitblit softcursor
Nov  3 22:53:38 t61p kernel: [ 8066.258668] Pid: 4910, comm: usb-storage Tainted: P           2.6.28-16-generic #55-Ubuntu
Nov  3 22:53:38 t61p kernel: [ 8066.258673] RIP: 0010:[<ffffffff802e2a5a>]  [<ffffffff802e2a5a>] kfree+0xfa/0x100
Nov  3 22:53:38 t61p kernel: [ 8066.258689] RSP: 0018:ffff88010e8fdc90  EFLAGS: 00010246
Nov  3 22:53:38 t61p kernel: [ 8066.258693] RAX: 8000000000040000 RBX: ffffe20003800000 RCX: ffff88002802cc80
Nov  3 22:53:38 t61p kernel: [ 8066.258698] RDX: ffffe20000000000 RSI: ffffffff805301e0 RDI: ffff880100000000
Nov  3 22:53:38 t61p kernel: [ 8066.258702] RBP: ffff88010e8fdcc0 R08: ffff88010e8fc000 R09: 0000000000000001
Nov  3 22:53:38 t61p kernel: [ 8066.258707] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801175e3768
Nov  3 22:53:38 t61p kernel: [ 8066.258711] R13: ffff880100000000 R14: 0000000000000001 R15: ffff8801175e3730
Nov  3 22:53:38 t61p kernel: [ 8066.258717] FS:  0000000000000000(0000) GS:ffffffff80a9b000(0000) knlGS:0000000000000000
Nov  3 22:53:38 t61p kernel: [ 8066.258722] CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
Nov  3 22:53:38 t61p kernel: [ 8066.258726] CR2: 00007f82302d3000 CR3: 0000000000201000 CR4: 00000000000006a0
Nov  3 22:53:38 t61p kernel: [ 8066.258731] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
Nov  3 22:53:38 t61p kernel: [ 8066.258736] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Nov  3 22:53:38 t61p kernel: [ 8066.258741] Process usb-storage (pid: 4910, threadinfo ffff88010e8fc000, task ffff88012009c320)
Nov  3 22:53:38 t61p kernel: [ 8066.258746] Stack:
Nov  3 22:53:38 t61p kernel: [ 8066.258749]  ffff88010e8fdcb0 ffff8801175e3720 ffff8801175e3768 0000000000000000
Nov  3 22:53:38 t61p kernel: [ 8066.258757]  0000000000000001 ffff8801175e3730 ffff88010e8fdce0 ffffffff80530aee
Nov  3 22:53:38 t61p kernel: [ 8066.258766]  ffff88010e8fdce0 ffff8801175e3720 ffff88010e8fdd20 ffffffff80530c85
Nov  3 22:53:38 t61p kernel: [ 8066.258776] Call Trace:
Nov  3 22:53:38 t61p kernel: [ 8066.258780]  [<ffffffff80530aee>] sg_clean+0x3e/0x80
Nov  3 22:53:38 t61p kernel: [ 8066.258789]  [<ffffffff80530c85>] usb_sg_wait+0x155/0x1b0
Nov  3 22:53:38 t61p kernel: [ 8066.258797]  [<ffffffffa0d98885>] usb_stor_bulk_transfer_sglist+0xa5/0xf0 [usb_storage]
Nov  3 22:53:38 t61p kernel: [ 8066.258818]  [<ffffffffa0d988f0>] usb_stor_bulk_srb+0x20/0x30 [usb_storage]
Nov  3 22:53:38 t61p kernel: [ 8066.258834]  [<ffffffffa0d98d2e>] usb_stor_Bulk_transport+0x11e/0x340 [usb_storage]
Nov  3 22:53:38 t61p kernel: [ 8066.258850]  [<ffffffffa0d9824a>] usb_stor_invoke_transport+0xfa/0x2e0 [usb_storage]
Nov  3 22:53:38 t61p kernel: [ 8066.258866]  [<ffffffffa0d97dc9>] usb_stor_transparent_scsi_command+0x9/0x10 [usb_storage]
Nov  3 22:53:38 t61p kernel: [ 8066.258881]  [<ffffffffa0d9a16f>] usb_stor_control_thread+0x15f/0x240 [usb_storage]
Nov  3 22:53:38 t61p kernel: [ 8066.258897]  [<ffffffffa0d9a010>] ? usb_stor_control_thread+0x0/0x240 [usb_storage]
Nov  3 22:53:38 t61p kernel: [ 8066.258912]  [<ffffffff80268689>] kthread+0x49/0x90
Nov  3 22:53:38 t61p kernel: [ 8066.258922]  [<ffffffff80213979>] child_rip+0xa/0x11
Nov  3 22:53:38 t61p kernel: [ 8066.258930]  [<ffffffff80268640>] ? kthread+0x0/0x90
Nov  3 22:53:38 t61p kernel: [ 8066.258937]  [<ffffffff8021396f>] ? child_rip+0x0/0x11
Nov  3 22:53:38 t61p kernel: [ 8066.258944] Code: 90 8b 41 10 85 c0 78 c2 8b 51 14 48 8b 01 49 89 44 d5 00 4c 89 29 eb c7 f6 c4 60 74 0e 48 89 df e8 6c 7c fd ff 0f 1f 40 00 eb bf <0f> 0b eb fe 66 90 55 48 81 ef a8 00 00 00 48 89 e5 e8 f0 fe ff 
Nov  3 22:53:38 t61p kernel: [ 8066.259020] RIP  [<ffffffff802e2a5a>] kfree+0xfa/0x100
Nov  3 22:53:38 t61p kernel: [ 8066.259027]  RSP <ffff88010e8fdc90>
Nov  3 22:53:38 t61p kernel: [ 8066.259033] ---[ end trace d04d7f9e6d74d35c ]---
Nov  3 22:53:55 t61p NetworkManager: <info>  HAL disappeared 
Nov  3 22:53:55 t61p kernel: [ 8083.252457] general protection fault: 0000 [#2] SMP 
Nov  3 22:53:55 t61p kernel: [ 8083.252468] last sysfs file: /sys/devices/LNXSYSTM:00/device:00/PNP0A08:00/device:01/PNP0C09:00/PNP0C0A:00/power_supply/BAT0/present
Nov  3 22:53:55 t61p kernel: [ 8083.252475] CPU 0 
Nov  3 22:53:55 t61p kernel: [ 8083.252479] Modules linked in: usb_storage binfmt_misc bridge stp bnep vboxnetadp vboxnetflt vboxdrv vmnet ppdev parport_pc vmblock vsock vmci vmmon input_polldev lp parport snd_hda_intel snd_pcm_oss snd_mixer_oss joydev snd_pcm snd_seq_dummy snd_seq_oss arc4 snd_seq_midi snd_rawmidi ecb snd_seq_midi_event pcmcia snd_seq iwlagn iwlcore snd_timer snd_seq_device yenta_socket thinkpad_acpi mac80211 snd video rsrc_nonstatic led_class psmouse soundcore intel_agp pcmcia_core iTCO_wdt iTCO_vendor_support output sierra usbserial nvram btusb pcspkr ricoh_mmc sdhci_pci sdhci serio_raw cfg80211 snd_page_alloc nvidia(P) usbhid ohci1394 ieee1394 e1000e fbcon tileblit font bitblit softcursor
Nov  3 22:53:55 t61p kernel: [ 8083.252589] Pid: 3334, comm: hald Tainted: P      D    2.6.28-16-generic #55-Ubuntu
Nov  3 22:53:55 t61p kernel: [ 8083.252594] RIP: 0010:[<ffffffff802e3504>]  [<ffffffff802e3504>] __kmalloc+0x74/0x110
Nov  3 22:53:55 t61p kernel: [ 8083.252610] RSP: 0018:ffff88012fc01bd8  EFLAGS: 00010082
Nov  3 22:53:55 t61p kernel: [ 8083.252615] RAX: 0000000000000000 RBX: 8d9700c3a00000bc RCX: 0000000000000004
Nov  3 22:53:55 t61p kernel: [ 8083.252620] RDX: ffff88002802cca0 RSI: 00000000000080d0 RDI: 0000000000000008
Nov  3 22:53:55 t61p kernel: [ 8083.252625] RBP: ffff88012fc01c08 R08: 0000000000000000 R09: ffff88012a1a7d40
Nov  3 22:53:55 t61p kernel: [ 8083.252629] R10: 0000000000000000 R11: 0000000000000246 R12: ffffffff809abcb8
Nov  3 22:53:55 t61p kernel: [ 8083.252634] R13: 0000000000000282 R14: 00000000000080d0 R15: ffffffff80460262
Nov  3 22:53:55 t61p kernel: [ 8083.252640] FS:  00007f46604926f0(0000) GS:ffffffff80a9b000(0000) knlGS:0000000000000000
Nov  3 22:53:55 t61p kernel: [ 8083.252645] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
Nov  3 22:53:55 t61p kernel: [ 8083.252649] CR2: 00007f823032d000 CR3: 000000013a06c000 CR4: 00000000000006a0
Nov  3 22:53:55 t61p kernel: [ 8083.252655] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
Nov  3 22:53:55 t61p kernel: [ 8083.252659] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Nov  3 22:53:55 t61p kernel: [ 8083.252665] Process hald (pid: 3334, threadinfo ffff88012fc00000, task ffff88013a58acc0)
Nov  3 22:53:55 t61p kernel: [ 8083.252669] Stack:
Nov  3 22:53:55 t61p kernel: [ 8083.252672]  000000082fc01be8 0000000000000008 0000000000000004 ffff88012fc01c38
Nov  3 22:53:55 t61p kernel: [ 8083.252680]  ffff88012fc01d00 ffffffff8081a0a4 ffff88012fc01c28 ffffffff80460262
Nov  3 22:53:55 t61p kernel: [ 8083.252690]  ffff88007f47e060 ffff88012a1a7d60 ffff88012fc01c88 ffffffff80460458
Nov  3 22:53:55 t61p kernel: [ 8083.252700] Call Trace:
Nov  3 22:53:55 t61p kernel: [ 8083.252704]  [<ffffffff80460262>] acpi_os_allocate_zeroed+0x37/0x3b
Nov  3 22:53:55 t61p kernel: [ 8083.252718]  [<ffffffff80460458>] acpi_ns_internalize_name+0x3f/0x7f
Nov  3 22:53:55 t61p kernel: [ 8083.252728]  [<ffffffff804604d9>] acpi_ns_get_node+0x41/0xa1
Nov  3 22:53:55 t61p kernel: [ 8083.252736]  [<ffffffff802f191c>] ? path_put+0x2c/0x40
Nov  3 22:53:55 t61p kernel: [ 8083.252744]  [<ffffffff802b6521>] ? prep_new_page+0xf1/0x1a0
Nov  3 22:53:55 t61p kernel: [ 8083.252753]  [<ffffffff8045fba3>] acpi_ns_evaluate+0x3f/0x230
Nov  3 22:53:55 t61p kernel: [ 8083.252761]  [<ffffffff8045f777>] acpi_evaluate_object+0xfc/0x205
Nov  3 22:53:55 t61p kernel: [ 8083.252769]  [<ffffffff802b6986>] ? get_page_from_freelist+0xd6/0x190
Nov  3 22:53:55 t61p kernel: [ 8083.252777]  [<ffffffff8046ddaf>] acpi_battery_get_state+0x80/0xf4
Nov  3 22:53:55 t61p kernel: [ 8083.252787]  [<ffffffff8046e0c5>] acpi_battery_get_property+0x2c/0x1aa
Nov  3 22:53:55 t61p kernel: [ 8083.252795]  [<ffffffff80562de4>] power_supply_show_property+0x54/0x150
Nov  3 22:53:55 t61p kernel: [ 8083.252804]  [<ffffffff804b767d>] dev_attr_show+0x2d/0x70
Nov  3 22:53:55 t61p kernel: [ 8083.252813]  [<ffffffff80347ca0>] sysfs_read_file+0xb0/0x170
Nov  3 22:53:55 t61p kernel: [ 8083.252822]  [<ffffffff802e8488>] vfs_read+0xc8/0x130
Nov  3 22:53:55 t61p kernel: [ 8083.252830]  [<ffffffff802e85e0>] sys_read+0x50/0x90
Nov  3 22:53:55 t61p kernel: [ 8083.252837]  [<ffffffff8021253a>] system_call_fastpath+0x16/0x1b
Nov  3 22:53:55 t61p kernel: [ 8083.252846] Code: fa 0f 1f 80 00 00 00 00 65 8b 04 25 24 00 00 00 48 98 49 8b 94 c4 e8 00 00 00 8b 7a 18 89 7d d4 48 8b 1a 48 85 db 74 4f 8b 42 14 <48> 8b 04 c3 48 89 02 4c 89 ef 57 9d 66 0f 1f 44 00 00 66 45 85 
Nov  3 22:53:55 t61p kernel: [ 8083.252923] RIP  [<ffffffff802e3504>] __kmalloc+0x74/0x110
Nov  3 22:53:55 t61p kernel: [ 8083.252930]  RSP <ffff88012fc01bd8>
Nov  3 22:53:55 t61p kernel: [ 8083.252936] ---[ end trace d04d7f9e6d74d35c ]---
Nov  3 22:53:58 t61p kernel: [ 8087.029782] general protection fault: 0000 [#3] SMP 
Nov  3 22:53:58 t61p kernel: [ 8087.029793] last sysfs file: /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
Nov  3 22:53:58 t61p kernel: [ 8087.029799] CPU 0 
Nov  3 22:53:58 t61p kernel: [ 8087.029803] Modules linked in: usb_storage binfmt_misc bridge stp bnep vboxnetadp vboxnetflt vboxdrv vmnet ppdev parport_pc vmblock vsock vmci vmmon input_polldev lp parport snd_hda_intel snd_pcm_oss snd_mixer_oss joydev snd_pcm snd_seq_dummy snd_seq_oss arc4 snd_seq_midi snd_rawmidi ecb snd_seq_midi_event pcmcia snd_seq iwlagn iwlcore snd_timer snd_seq_device yenta_socket thinkpad_acpi mac80211 snd video rsrc_nonstatic led_class psmouse soundcore intel_agp pcmcia_core iTCO_wdt iTCO_vendor_support output sierra usbserial nvram btusb pcspkr ricoh_mmc sdhci_pci sdhci serio_raw cfg80211 snd_page_alloc nvidia(P) usbhid ohci1394 ieee1394 e1000e fbcon tileblit font bitblit softcursor
Nov  3 22:53:58 t61p kernel: [ 8087.029912] Pid: 4071, comm: Xorg Tainted: P      D    2.6.28-16-generic #55-Ubuntu
Nov  3 22:53:58 t61p kernel: [ 8087.029917] RIP: 0010:[<ffffffff802e3504>]  [<ffffffff802e3504>] __kmalloc+0x74/0x110
Nov  3 22:53:58 t61p kernel: [ 8087.029934] RSP: 0018:ffff88012b06bd18  EFLAGS: 00010082
Nov  3 22:53:58 t61p kernel: [ 8087.029938] RAX: 0000000000000000 RBX: 8d9700c3a00000bc RCX: 0000000000000002
Nov  3 22:53:58 t61p kernel: [ 8087.029943] RDX: ffff88002802cca0 RSI: 00000000000002d0 RDI: 0000000000000008
Nov  3 22:53:58 t61p kernel: [ 8087.029948] RBP: ffff88012b06bd48 R08: 0000000000000004 R09: ffff88012b804000
Nov  3 22:53:58 t61p kernel: [ 8087.029952] R10: 0000000000000001 R11: 0000000000003206 R12: ffffffff809abcb8
Nov  3 22:53:58 t61p kernel: [ 8087.029957] R13: 0000000000000282 R14: 00000000000002d0 R15: ffffffffa04c9f78
Nov  3 22:53:58 t61p kernel: [ 8087.029963] FS:  00007ff8b3cc8700(0000) GS:ffffffff80a9b000(0000) knlGS:0000000000000000
Nov  3 22:53:58 t61p kernel: [ 8087.029968] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Nov  3 22:53:58 t61p kernel: [ 8087.029972] CR2: 00007f82243a9000 CR3: 000000012dd48000 CR4: 00000000000006a0
Nov  3 22:53:58 t61p kernel: [ 8087.029977] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
Nov  3 22:53:58 t61p kernel: [ 8087.029982] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Nov  3 22:53:58 t61p kernel: [ 8087.029987] Process Xorg (pid: 4071, threadinfo ffff88012b06a000, task ffff8801398cd980)
Nov  3 22:53:58 t61p kernel: [ 8087.029991] Stack:
Nov  3 22:53:58 t61p kernel: [ 8087.029994]  0000000800000282 ffff88013a8aafa0 0000000000000004 0000000000000004
Nov  3 22:53:58 t61p kernel: [ 8087.030003]  00007fffedc25430 0000000000800185 ffff88012b06bd68 ffffffffa04c9f78
Nov  3 22:53:58 t61p kernel: [ 8087.030012]  0000000000000000 00000000c1d00026 ffff88013a8aaf90 ffffffffa03ffee4
Nov  3 22:53:58 t61p kernel: [ 8087.030023] Call Trace:
Nov  3 22:53:58 t61p kernel: [ 8087.030028]  [<ffffffffa04c9f78>] os_alloc_mem+0x68/0xe0 [nvidia]
Nov  3 22:53:58 t61p kernel: [ 8087.030405]  [<ffffffffa03ffee4>] _nv004412rm+0x12/0x21 [nvidia]
Nov  3 22:53:58 t61p kernel: [ 8087.030731]  [<ffffffffa0443145>] ? _nv003295rm+0xd5/0x1d9 [nvidia]
Nov  3 22:53:58 t61p kernel: [ 8087.031038]  [<ffffffffa0389e2e>] ? _nv006010rm+0x88/0x108 [nvidia]
Nov  3 22:53:58 t61p kernel: [ 8087.031359]  [<ffffffffa02095b8>] ? _nv003189rm+0x698/0x6fd [nvidia]
Nov  3 22:53:58 t61p kernel: [ 8087.031656]  [<ffffffffa040845d>] ? rm_ioctl+0x2f/0x67 [nvidia]
Nov  3 22:53:58 t61p kernel: [ 8087.031976]  [<ffffffffa04c5db3>] ? nv_kern_ioctl+0x1b3/0x480 [nvidia]
Nov  3 22:53:58 t61p kernel: [ 8087.032008]  [<ffffffffa04c60bc>] ? nv_kern_unlocked_ioctl+0x1c/0x20 [nvidia]
Nov  3 22:53:58 t61p kernel: [ 8087.032008]  [<ffffffff802f65f1>] ? vfs_ioctl+0x31/0xa0
Nov  3 22:53:58 t61p kernel: [ 8087.032008]  [<ffffffff802f69a5>] ? do_vfs_ioctl+0x75/0x230
Nov  3 22:53:58 t61p kernel: [ 8087.032008]  [<ffffffff802f6bf9>] ? sys_ioctl+0x99/0xa0
Nov  3 22:53:58 t61p kernel: [ 8087.032008]  [<ffffffff80211f29>] ? sys_rt_sigreturn+0x9/0x10
Nov  3 22:53:58 t61p kernel: [ 8087.032008]  [<ffffffff8021253a>] ? system_call_fastpath+0x16/0x1b
Nov  3 22:53:58 t61p kernel: [ 8087.032008] Code: fa 0f 1f 80 00 00 00 00 65 8b 04 25 24 00 00 00 48 98 49 8b 94 c4 e8 00 00 00 8b 7a 18 89 7d d4 48 8b 1a 48 85 db 74 4f 8b 42 14 <48> 8b 04 c3 48 89 02 4c 89 ef 57 9d 66 0f 1f 44 00 00 66 45 85 
Nov  3 22:53:58 t61p kernel: [ 8087.032008] RIP  [<ffffffff802e3504>] __kmalloc+0x74/0x110
Nov  3 22:53:58 t61p kernel: [ 8087.032008]  RSP <ffff88012b06bd18>
Nov  3 22:53:58 t61p kernel: [ 8087.032008] ---[ end trace d04d7f9e6d74d35c ]---
Nov  3 22:55:01 t61p /USR/SBIN/CRON[8087]: (root) CMD ([ -x /usr/lib/sysstat/sa1 ] && { [ -r "$DEFAULT" ] && . "$DEFAULT" ; [ "$ENABLED" = "true" ] && exec /usr/lib/sysstat/sa1 $SA1_OPTIONS 1 1 ; })
Nov  3 22:56:31 t61p dhclient: DHCPREQUEST of 192.168.5.174 on wlan0 to 192.168.5.254 port 67
Nov  3 22:56:31 t61p dhclient: DHCPACK of 192.168.5.174 from 192.168.5.254
Nov  3 22:56:31 t61p dhclient: bound to 192.168.5.174 -- renewal in 421 seconds.
Nov  3 22:58:22 t61p syslogd 1.5.0#5ubuntu3: restart.
Nov  3 22:58:22 t61p kernel: Inspecting /boot/System.map-2.6.28-16-generic
Nov  3 22:58:22 t61p kernel: Cannot find map file.
Nov  3 22:58:22 t61p kernel: Loaded 80100 symbols from 58 modules.


About 20 minutes after this was logged, the system "froze hard" (CAPS LOCK blinking) after trying to close a window (at this point Compiz was running too; I have now turned it off to see if this will help).

Nov  4 22:17:00 t61p kernel: [ 4379.070399] usb 2-1: USB disconnect, address 6
Nov  4 22:17:00 t61p kernel: [ 4379.074170] BUG: unable to handle kernel paging request at ffffe3a400000000
Nov  4 22:17:00 t61p kernel: [ 4379.074180] IP: [<ffffffff802e3b4b>] kmem_cache_free+0x4b/0xe0
Nov  4 22:17:00 t61p kernel: [ 4379.074196] PGD 0 
Nov  4 22:17:00 t61p kernel: [ 4379.074201] Oops: 0000 [#1] SMP 
Nov  4 22:17:00 t61p kernel: [ 4379.074207] last sysfs file: /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
Nov  4 22:17:00 t61p kernel: [ 4379.074213] Dumping ftrace buffer:
Nov  4 22:17:00 t61p kernel: [ 4379.074217]    (ftrace buffer empty)
Nov  4 22:17:00 t61p kernel: [ 4379.074221] CPU 1 
Nov  4 22:17:00 t61p kernel: [ 4379.074224] Modules linked in: nls_iso8859_1 nls_cp437 vfat fat binfmt_misc bridge stp bnep vboxnetadp vboxnetflt vboxdrv vmnet ppdev parport_pc vmblock vsock vmci vmmon input_polldev lp parport snd_hda_intel snd_pcm_oss snd_mixer_oss snd_pcm joydev snd_seq_dummy snd_seq_oss snd_seq_midi arc4 snd_rawmidi snd_seq_midi_event ecb snd_seq pcmcia snd_timer iwlagn iwlcore snd_seq_device yenta_socket thinkpad_acpi mac80211 snd sierra rsrc_nonstatic video led_class psmouse soundcore usbserial pcmcia_core iTCO_wdt iTCO_vendor_support output nvram btusb intel_agp sdhci_pci sdhci ricoh_mmc pcspkr serio_raw cfg80211 snd_page_alloc nvidia(P) usbhid usb_storage ohci1394 ieee1394 e1000e fbcon tileblit font bitblit softcursor
Nov  4 22:17:00 t61p kernel: [ 4379.074339] Pid: 25, comm: khubd Tainted: P           2.6.28-16-generic #55-Ubuntu
Nov  4 22:17:00 t61p kernel: [ 4379.074343] RIP: 0010:[<ffffffff802e3b4b>]  [<ffffffff802e3b4b>] kmem_cache_free+0x4b/0xe0
Nov  4 22:17:00 t61p kernel: [ 4379.074353] RSP: 0018:ffff88013b0b98e0  EFLAGS: 00010206
Nov  4 22:17:00 t61p kernel: [ 4379.074357] RAX: 000001a400000000 RBX: ffffe3a400000000 RCX: 0000000000000002
Nov  4 22:17:00 t61p kernel: [ 4379.074362] RDX: ffffe20000000000 RSI: 0000000000000000 RDI: 0000000000000000
Nov  4 22:17:00 t61p kernel: [ 4379.074366] RBP: ffff88013b0b9910 R08: 0000000000000000 R09: ffffffff809ae570
Nov  4 22:17:00 t61p kernel: [ 4379.074371] R10: 0000000000000002 R11: 0000000000000000 R12: ffff880139707088
Nov  4 22:17:00 t61p kernel: [ 4379.074375] R13: 0000000000000000 R14: ffff88012a1b5000 R15: ffff88013bb57800
Nov  4 22:17:00 t61p kernel: [ 4379.074381] FS:  0000000000000000(0000) GS:ffff88013b803c80(0000) knlGS:0000000000000000
Nov  4 22:17:00 t61p kernel: [ 4379.074386] CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
Nov  4 22:17:00 t61p kernel: [ 4379.074390] CR2: ffffe3a400000000 CR3: 0000000000201000 CR4: 00000000000006a0
Nov  4 22:17:00 t61p kernel: [ 4379.074395] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
Nov  4 22:17:00 t61p kernel: [ 4379.074399] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Nov  4 22:17:00 t61p kernel: [ 4379.074405] Process khubd (pid: 25, threadinfo ffff88013b0b8000, task ffff88013b0b0000)
Nov  4 22:17:00 t61p kernel: [ 4379.074409] Stack:
Nov  4 22:17:00 t61p kernel: [ 4379.074412]  ffff88013b0b9910 ffff8800bb1bf9c0 ffff880139707088 ffff8801395d2e10
Nov  4 22:17:00 t61p kernel: [ 4379.074420]  ffff88012a1b5000 ffff88012d171828 ffff88013b0b9920 ffffffff802b33e2
Nov  4 22:17:00 t61p kernel: [ 4379.074429]  ffff88013b0b9940 ffffffff802b3321 ffff88013b0b9950 ffff880139707300
Nov  4 22:17:00 t61p kernel: [ 4379.074439] Call Trace:
Nov  4 22:17:00 t61p kernel: [ 4379.074443]  [<ffffffff802b33e2>] mempool_free_slab+0x12/0x20
Nov  4 22:17:00 t61p kernel: [ 4379.074452]  [<ffffffff802b3321>] free_pool+0x31/0x60
Nov  4 22:17:00 t61p kernel: [ 4379.074460]  [<ffffffff802b3361>] mempool_destroy+0x11/0x20
Nov  4 22:17:00 t61p kernel: [ 4379.074466]  [<ffffffff80408c8a>] blk_release_queue+0x2a/0x70
Nov  4 22:17:00 t61p kernel: [ 4379.074476]  [<ffffffff8041953a>] kobject_release+0x4a/0xa0
Nov  4 22:17:00 t61p kernel: [ 4379.074484]  [<ffffffff804194f0>] ? kobject_release+0x0/0xa0
Nov  4 22:17:00 t61p kernel: [ 4379.074491]  [<ffffffff8041a5a7>] kref_put+0x37/0x70
Nov  4 22:17:00 t61p kernel: [ 4379.074498]  [<ffffffff804193f7>] kobject_put+0x27/0x60
Nov  4 22:17:00 t61p kernel: [ 4379.074504]  [<ffffffff80405eff>] blk_cleanup_queue+0x5f/0x70
Nov  4 22:17:00 t61p kernel: [ 4379.074512]  [<ffffffff804d8299>] scsi_free_queue+0x9/0x10
Nov  4 22:17:00 t61p kernel: [ 4379.074521]  [<ffffffff804de433>] scsi_device_dev_release_usercontext+0x163/0x1c0
Nov  4 22:17:00 t61p kernel: [ 4379.074530]  [<ffffffff8026502a>] execute_in_process_context+0x4a/0x60
Nov  4 22:17:00 t61p kernel: [ 4379.074539]  [<ffffffff804de2c7>] scsi_device_dev_release+0x17/0x20
Nov  4 22:17:00 t61p kernel: [ 4379.074546]  [<ffffffff804b76d9>] device_release+0x19/0x80
Nov  4 22:17:00 t61p kernel: [ 4379.074555]  [<ffffffff8041953a>] kobject_release+0x4a/0xa0
Nov  4 22:17:00 t61p kernel: [ 4379.074562]  [<ffffffff804194f0>] ? kobject_release+0x0/0xa0
Nov  4 22:17:00 t61p kernel: [ 4379.074568]  [<ffffffff8041a5a7>] kref_put+0x37/0x70
Nov  4 22:17:00 t61p kernel: [ 4379.074575]  [<ffffffff804193f7>] kobject_put+0x27/0x60
Nov  4 22:17:00 t61p kernel: [ 4379.074581]  [<ffffffff804b6f25>] put_device+0x15/0x20
Nov  4 22:17:00 t61p kernel: [ 4379.074588]  [<ffffffff804de91b>] __scsi_remove_device+0x8b/0x90
Nov  4 22:17:00 t61p kernel: [ 4379.074595]  [<ffffffff804dafba>] scsi_forget_host+0x6a/0x70
Nov  4 22:17:00 t61p kernel: [ 4379.074602]  [<ffffffff804d30bc>] scsi_remove_host+0x6c/0x120
Nov  4 22:17:00 t61p kernel: [ 4379.074611]  [<ffffffffa007f4a1>] quiesce_and_remove_host+0x71/0xd0 [usb_storage]
Nov  4 22:17:00 t61p kernel: [ 4379.074636]  [<ffffffffa007f5e8>] storage_disconnect+0x18/0x30 [usb_storage]
Nov  4 22:17:00 t61p kernel: [ 4379.074654]  [<ffffffff80533832>] usb_unbind_interface+0x62/0x150
Nov  4 22:17:00 t61p kernel: [ 4379.074665]  [<ffffffff804ba4fd>] __device_release_driver+0x9d/0xe0
Nov  4 22:17:00 t61p kernel: [ 4379.074672]  [<ffffffff804ba64b>] device_release_driver+0x2b/0x40
Nov  4 22:17:00 t61p kernel: [ 4379.074679]  [<ffffffff804b9990>] bus_remove_device+0xb0/0xf0
Nov  4 22:17:00 t61p kernel: [ 4379.074685]  [<ffffffff804b7d5d>] device_del+0x10d/0x1e0
Nov  4 22:17:00 t61p kernel: [ 4379.074693]  [<ffffffff80530659>] usb_disable_device+0xb9/0x140
Nov  4 22:17:00 t61p kernel: [ 4379.074700]  [<ffffffff8052b91c>] usb_disconnect+0xbc/0x180
Nov  4 22:17:00 t61p kernel: [ 4379.074708]  [<ffffffff8052bfbe>] hub_port_connect_change+0x1be/0xab0
Nov  4 22:17:00 t61p kernel: [ 4379.074715]  [<ffffffff8052fe95>] ? usb_free_urb+0x15/0x20
Nov  4 22:17:00 t61p kernel: [ 4379.074723]  [<ffffffff80531081>] ? usb_start_wait_urb+0x91/0xe0
Nov  4 22:17:00 t61p kernel: [ 4379.074730]  [<ffffffff8053131f>] ? usb_control_msg+0xef/0x110
Nov  4 22:17:00 t61p kernel: [ 4379.074737]  [<ffffffff8052ccb3>] hub_events+0x2e3/0x670
Nov  4 22:17:00 t61p kernel: [ 4379.074744]  [<ffffffff8052d07d>] hub_thread+0x3d/0x180
Nov  4 22:17:00 t61p kernel: [ 4379.074752]  [<ffffffff80268af0>] ? autoremove_wake_function+0x0/0x40
Nov  4 22:17:00 t61p kernel: [ 4379.074760]  [<ffffffff8052d040>] ? hub_thread+0x0/0x180
Nov  4 22:17:00 t61p kernel: [ 4379.074767]  [<ffffffff80268689>] kthread+0x49/0x90
Nov  4 22:17:00 t61p kernel: [ 4379.074774]  [<ffffffff80213979>] child_rip+0xa/0x11
Nov  4 22:17:00 t61p kernel: [ 4379.074782]  [<ffffffff80268640>] ? kthread+0x0/0x90
Nov  4 22:17:00 t61p kernel: [ 4379.074789]  [<ffffffff8021396f>] ? child_rip+0x0/0x11
Nov  4 22:17:00 t61p kernel: [ 4379.074795] Code: e0 4c 89 75 f0 e8 26 2a f5 ff 48 c1 e8 0c 48 8d 14 c5 00 00 00 00 48 c1 e0 06 48 29 d0 48 ba 00 00 00 00 00 e2 ff ff 48 8d 1c 10 <48> 8b 03 f6 c4 40 74 04 48 8b 5b 10 4c 8b 75 08 9c 58 66 0f 1f 
Nov  4 22:17:00 t61p kernel: [ 4379.074872] RIP  [<ffffffff802e3b4b>] kmem_cache_free+0x4b/0xe0
Nov  4 22:17:00 t61p kernel: [ 4379.074880]  RSP <ffff88013b0b98e0>
Nov  4 22:17:00 t61p kernel: [ 4379.074883] CR2: ffffe3a400000000
Nov  4 22:17:00 t61p kernel: [ 4379.074888] ---[ end trace 7e43dafe495e2e18 ]---