I think the bug has been fixed in 3.3-rc4, and the commit is below:

commit bced76aeaca03b45e3b4bdb868cada328e497847
Author: Peter Zijlstra <email address hidden>
Date:   Wed Jan 11 13:11:12 2012 +0100

    sched: Fix lockup by limiting load-balance retries on lock-break

Bryce, so could you feedback the test result with -rc4?


On Thu, Feb 23, 2012 at 5:11 AM, Joseph Salisbury
<email address hidden> wrote:
> It would be great if you could test with 3.3-rc4-precise.  This could
> also test if the issue in bug 938894 is resolved upstream.
>
> --
> You received this bug notification because you are subscribed to linux
> in Ubuntu.
> https://bugs.launchpad.net/bugs/917668
>
> Title:
>  system freeze ("hard LOCKUP"), warn_slowpath_common+0x7f in
>  sock_aio_read
>
> Status in “linux” package in Ubuntu:
>  Incomplete
>
> Bug description:
>  I've had sporadic freezes on this system before since upgrading to
>  Precise, but I haven't had the resources to try and ssh in prior to
>  this, so I can't tell if this has occurred before. Now that I have an
>  additional laptop I can hopefully catch this again if it occurs.
>
>  I screwed up with the logs first, but then managed to salvage dmesg
>  with a Trace from terminal buffer. I'll attach it separately below.
>
>  I wasn't active on the desktop when the freeze happened (had my hands
>  on the laptop). At least Chromium, Transmission and Google Music were
>  running at the time.
>
>  (I'm not familiar with Traces so I'll just pick something from the
>  first line as title. Feel free to change it if needed.)
>
>  [19199.961223] ------------[ cut here ]------------
>  [19199.961223] WARNING: at /build/buildd/linux-3.2.0/kernel/watchdog.c:241 watchdog_overflow_callback+0x9a/0xc0()
>  [19199.961223] Hardware name: System Product Name
>  [19199.961223] Watchdog detected hard LOCKUP on cpu 0
>  [19199.961223] Modules linked in: nls_iso8859_1 nls_cp437 vfat fat sit tunnel4 bnep rfcomm binfmt_misc dm_crypt snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_seq_midi usbhid snd_rawmidi snd_seq_midi_event btusb bluetooth hid snd_seq snd_timer snd_seq_device snd sp5100_tco soundcore snd_page_alloc i2c_piix4 edac_core shpchp dm_multipath ppdev asus_atk0110 edac_mce_amd k10temp mac_hid parport_pc lp parport usb_storage uas dm_raid45 xor dm_mirror dm_region_hash dm_log radeon ttm drm_kms_helper drm r8169 wmi i2c_algo_bit pata_atiixp
>  [19199.961223] Pid: 1387, comm: Xorg Not tainted 3.2.0-9-generic #16-Ubuntu
>  [19199.961223] Call Trace:
>  [19199.961223]  <NMI>  [<ffffffff810651df>] warn_slowpath_common+0x7f/0xc0
>  [19199.961223]  [<ffffffff810652d6>] warn_slowpath_fmt+0x46/0x50
>  [19199.961223]  [<ffffffff8101adf9>] ? sched_clock+0x9/0x10
>  [19199.961223]  [<ffffffff810d5fba>] watchdog_overflow_callback+0x9a/0xc0
>  [19199.961223]  [<ffffffff81110736>] __perf_event_overflow+0x96/0x1e0
>  [19199.961223]  [<ffffffff8110dcc1>] ? perf_event_update_userpage+0x11/0xc0
>  [19199.961223]  [<ffffffff81110c84>] perf_event_overflow+0x14/0x20
>  [19199.961223]  [<ffffffff81023fc7>] x86_pmu_handle_irq+0xd7/0x120
>  [19199.961223]  [<ffffffff816559c1>] perf_event_nmi_handler+0x21/0x30
>  [19199.961223]  [<ffffffff81655289>] default_do_nmi+0x69/0x220
>  [19199.961223]  [<ffffffff816554c0>] do_nmi+0x80/0x90
>  [19199.961223]  [<ffffffff816548b0>] nmi+0x20/0x30
>  [19199.961223]  [<ffffffff8103ba95>] ? __ticket_spin_lock+0x25/0x30
>  [19199.961223]  <<EOE>>  [<ffffffff8103bb29>] default_spin_lock_flags+0x9/0x10
>  [19199.961223]  [<ffffffff816540fe>] _raw_spin_lock_irqsave+0x2e/0x40
>  [19199.961223]  [<ffffffff81088cc0>] remove_wait_queue+0x20/0x70
>  [19199.961223]  [<ffffffff811890d8>] poll_freewait+0x98/0xe0
>  [19199.961223]  [<ffffffff81189c17>] do_select+0x557/0x600
>  [19199.961223]  [<ffffffff8105d99e>] ? try_to_wake_up+0x18e/0x200
>  [19199.961223]  [<ffffffff81189120>] ? poll_freewait+0xe0/0xe0
>  [19199.961223]  [<ffffffff81189210>] ? __pollwait+0xf0/0xf0
>  [19199.961223]  [<ffffffff81189210>] ? __pollwait+0xf0/0xf0
>  [19199.961223]  [<ffffffff81189210>] ? __pollwait+0xf0/0xf0
>  [19199.961223]  [<ffffffff81189210>] ? __pollwait+0xf0/0xf0
>  [19199.961223]  [<ffffffff81189210>] ? __pollwait+0xf0/0xf0
>  [19199.961223]  [<ffffffff81189210>] ? __pollwait+0xf0/0xf0
>  [19199.961223]  [<ffffffff81189210>] ? __pollwait+0xf0/0xf0
>  [19199.961223]  [<ffffffff81189210>] ? __pollwait+0xf0/0xf0
>  [19199.961223]  [<ffffffff81189210>] ? __pollwait+0xf0/0xf0
>  [19199.961223]  [<ffffffff81189eac>] core_sys_select+0x1ec/0x370
>  [19199.961223]  [<ffffffff815241ad>] ? sock_aio_read+0x2d/0x40
>  [19199.961223]  [<ffffffff81175c02>] ? do_sync_read+0xd2/0x110
>  [19199.961223]  [<ffffffff8130fc24>] ? timerqueue_del+0x34/0x90
>  [19199.961223]  [<ffffffff8108c6a0>] ? __remove_hrtimer+0x60/0xc0
>  [19199.961223]  [<ffffffff8108cc80>] ? hrtimer_try_to_cancel+0x50/0xc0
>  [19199.961223]  [<ffffffff8101a6f9>] ? read_tsc+0x9/0x20
>  [19199.961223]  [<ffffffff81092f3d>] ? ktime_get_ts+0xad/0xe0
>  [19199.961223]  [<ffffffff8118a280>] sys_select+0xc0/0x100
>  [19199.961223]  [<ffffffff8165c3c2>] system_call_fastpath+0x16/0x1b
>  [19199.961223] ---[ end trace 104ea42b28f227b7 ]---
>
>
>  ProblemType: Bug
>  DistroRelease: Ubuntu 12.04
>  Package: xserver-xorg-video-radeon 1:6.14.99~git20110811.g93fc084-0ubuntu1
>  ProcVersionSignature: Ubuntu 3.2.0-9.16-generic 3.2.1
>  Uname: Linux 3.2.0-9-generic x86_64
>  .tmp.unity.support.test.0:
>
>  ApportVersion: 1.90-0ubuntu2
>  Architecture: amd64
>  CheckboxSubmission: 09ae689090491ca53449589269e4bfd8
>  CheckboxSystem: edda5d4f616ca792bf437989cb597002
>  CompizPlugins: [core,bailer,detection,composite,opengl,decor,resize,compiztoolbox,place,gnomecompat,regex,grid,mousepoll,snap,move,wall,imgpng,vpswitch,session,unitymtgrabhandles,animation,fade,workarounds,expo,scale,ezoom,unityshell]
>  CompositorRunning: None
>  Date: Tue Jan 17 16:09:07 2012
>  DistUpgraded: Log time: 2011-11-20 23:52:49.660633
>  DistroCodename: precise
>  DistroVariant: ubuntu
>  EcryptfsInUse: Yes
>  ExtraDebuggingInterest: Yes, whatever it takes to get this fixed in Ubuntu
>  GraphicsCard:
>   ATI Technologies Inc RS780 [Radeon HD 3200] [1002:9610] (prog-if 00 [VGA controller])
>     Subsystem: ASUSTeK Computer Inc. Device [1043:82f1]
>  InstallationMedia: Ubuntu 9.10 "Karmic Koala" - Release amd64 (20091027)
>  MachineType: System manufacturer System Product Name
>  ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.2.0-9-generic root=UUID=bf0f4d7e-d08c-4aad-8143-b6e3b16049d6 ro quiet splash radeon.audio=1 vt.handoff=7
>  SourcePackage: xserver-xorg-video-ati
>  UpgradeStatus: Upgraded to precise on 2012-01-17 (0 days ago)
>  dmi.bios.date: 08/12/2010
>  dmi.bios.vendor: American Megatrends Inc.
>  dmi.bios.version: 2101
>  dmi.board.asset.tag: To Be Filled By O.E.M.
>  dmi.board.name: M4A78-EM
>  dmi.board.vendor: ASUSTeK Computer INC.
>  dmi.board.version: Rev X.0x
>  dmi.chassis.asset.tag: Asset-1234567890
>  dmi.chassis.type: 3
>  dmi.chassis.vendor: Chassis Manufacture
>  dmi.chassis.version: Chassis Version
>  dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr2101:bd08/12/2010:svnSystemmanufacturer:pnSystemProductName:pvrSystemVersion:rvnASUSTeKComputerINC.:rnM4A78-EM:rvrRevX.0x:cvnChassisManufacture:ct3:cvrChassisVersion:
>  dmi.product.name: System Product Name
>  dmi.product.version: System Version
>  dmi.sys.vendor: System manufacturer
>  version.compiz: compiz 1:0.9.6+bzr20110929-0ubuntu8
>  version.ia32-libs: ia32-libs 20090808ubuntu33
>  version.libdrm2: libdrm2 2.4.30-1ubuntu1
>  version.libgl1-mesa-dri: libgl1-mesa-dri 7.11-0ubuntu4
>  version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
>  version.libgl1-mesa-glx: libgl1-mesa-glx 7.11-0ubuntu4
>  version.xserver-xorg-core: xserver-xorg-core 2:1.10.4-1ubuntu6
>  version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.6.0-1ubuntu13
>  version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.14.99~git20110811.g93fc084-0ubuntu1
>  version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.15.901-1ubuntu4
>  version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20111201+b5534a1-1
>
> To manage notifications about this bug go to:
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