The system freezes intermittently and the kernel crashes a few seconds later. This has only happened since upgrading to 11.10. Found the following error in /var/log/kern.log which coincides:

Oct 25 14:53:46 lt9630 kernel: [  737.900416] INFO: rcu_sched_state detected stall on CPU 2 (t=15000 jiffies)
Oct 25 14:55:46 lt9630 kernel: [  857.813946] [fglrx] ASIC hang happened
Oct 25 14:55:46 lt9630 kernel: [  857.813950] Pid: 1149, comm: Xorg Tainted: P         C  3.0.0-12-generic #20-Ubuntu
Oct 25 14:55:46 lt9630 kernel: [  857.813951] Call Trace:
Oct 25 14:55:46 lt9630 kernel: [  857.813985]  [<ffffffffa00a0d7e>] KCL_DEBUG_OsDump+0xe/0x10 [fglrx]
Oct 25 14:55:46 lt9630 kernel: [  857.814003]  [<ffffffffa00ae20c>] firegl_hardwareHangRecovery+0x1c/0x50 [fglrx]
Oct 25 14:55:46 lt9630 kernel: [  857.814036]  [<ffffffffa013ad59>] ? _ZN4Asic9WaitUntil15ResetASICIfHungEv+0x9/0x10 [fglrx]
Oct 25 14:55:46 lt9630 kernel: [  857.814068]  [<ffffffffa013ad0c>] ? _ZN4Asic9WaitUntil15WaitForCompleteEv+0x6c/0xb0 [fglrx]
Oct 25 14:55:46 lt9630 kernel: [  857.814099]  [<ffffffffa0135fb4>] ? _ZN15ExecutableUnits10CPRingIdleE15idle_WaitMethod12_QS_CP_RING_+0xe4$
Oct 25 14:55:46 lt9630 kernel: [  857.814127]  [<ffffffffa0115acb>] ? _ZN10CMMSurfaceD1Ev+0xcb/0xe0 [fglrx]
Oct 25 14:55:46 lt9630 kernel: [  857.814158]  [<ffffffffa0135e7b>] ? _ZN15ExecutableUnits7PM4idleE15idle_WaitMethod+0x4b/0x90 [fglrx]
Oct 25 14:55:46 lt9630 kernel: [  857.814187]  [<ffffffffa012e8f1>] ? _ZN15QS_PRIVATE_CORE9QsPM4idleE15idle_WaitMethod+0x31/0x60 [fglrx]
Oct 25 14:55:46 lt9630 kernel: [  857.814215]  [<ffffffffa0119d8a>] ? _ZN10QS_PRIVATE11synchronizeEv+0x2a/0x30 [fglrx]
Oct 25 14:55:46 lt9630 kernel: [  857.814243]  [<ffffffffa01233f5>] ? _Z8uCWDDEQCmjjPvjS_+0x3b5/0x10c0 [fglrx]
Oct 25 14:55:46 lt9630 kernel: [  857.814246]  [<ffffffff810871ee>] ? down+0x2e/0x50
Oct 25 14:55:46 lt9630 kernel: [  857.814266]  [<ffffffffa00cc932>] ? firegl_cmmqs_CWDDE_32+0x332/0x440 [fglrx]
Oct 25 14:55:46 lt9630 kernel: [  857.814285]  [<ffffffffa00cb260>] ? firegl_cmmqs_CWDDE32+0x70/0x100 [fglrx]
Oct 25 14:55:46 lt9630 kernel: [  857.814288]  [<ffffffff81282e5a>] ? security_capable+0x2a/0x30
Oct 25 14:55:46 lt9630 kernel: [  857.814306]  [<ffffffffa00cb1f0>] ? firegl_cmmqs_createdriver+0x170/0x170 [fglrx]
Oct 25 14:55:46 lt9630 kernel: [  857.814322]  [<ffffffffa00a9e18>] ? firegl_ioctl+0x1e8/0x250 [fglrx]
Oct 25 14:55:46 lt9630 kernel: [  857.814333]  [<ffffffffa009a9be>] ? ip_firegl_unlocked_ioctl+0xe/0x20 [fglrx]
Oct 25 14:55:46 lt9630 kernel: [  857.814335]  [<ffffffff8117939a>] ? do_vfs_ioctl+0x8a/0x340
Oct 25 14:55:46 lt9630 kernel: [  857.814338]  [<ffffffff811679ed>] ? vfs_read+0x10d/0x180
Oct 25 14:55:46 lt9630 kernel: [  857.814339]  [<ffffffff811796e1>] ? sys_ioctl+0x91/0xa0
Oct 25 14:55:46 lt9630 kernel: [  857.814342]  [<ffffffff815f22c2>] ? system_call_fastpath+0x16/0x1b
Oct 25 14:55:46 lt9630 kernel: [  857.814345] pubdev:0xffffffffa02fd600, num of device:1 , name:fglrx, major 8, minor 88.
Oct 25 14:55:46 lt9630 kernel: [  857.814346] device 0 : 0xffff88019b850000 .

Oct 25 14:55:46 lt9630 kernel: [  857.814345] pubdev:0xffffffffa02fd600, num of device:1 , name:fglrx, major 8, minor 88.
Oct 25 14:55:46 lt9630 kernel: [  857.814346] device 0 : 0xffff88019b850000 .
Oct 25 14:55:46 lt9630 kernel: [  857.814348] Asic ID:0x6779, revision:0x3c, MMIOReg:0xffffc90012b80000.
Oct 25 14:55:46 lt9630 kernel: [  857.814349] FB phys addr: 0xc0000000, MC :0xf00000000, Total FB size :0x40000000.
Oct 25 14:55:46 lt9630 kernel: [  857.814351] gart table MC:0xf0f8fd000, Physical:0xcf8fd000, size:0x402000.
Oct 25 14:55:46 lt9630 kernel: [  857.814353] mc_node :FB, total 1 zones
Oct 25 14:55:46 lt9630 kernel: [  857.814354]     MC start:0xf00000000, Physical:0xc0000000, size:0xfd00000.
Oct 25 14:55:46 lt9630 kernel: [  857.814356]     Mapped heap -- Offset:0x0, size:0xf8fd000, reference count:33, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814357]     Mapped heap -- Offset:0x0, size:0x1000000, reference count:1, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814359]     Mapped heap -- Offset:0xf8fd000, size:0x403000, reference count:1, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814360] mc_node :INV_FB, total 1 zones
Oct 25 14:55:46 lt9630 kernel: [  857.814362]     MC start:0xf0fd00000, Physical:0xcfd00000, size:0x30300000.
Oct 25 14:55:46 lt9630 kernel: [  857.814363]     Mapped heap -- Offset:0x302f4000, size:0xc000, reference count:1, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814365] mc_node :GART_USWC, total 2 zones
Oct 25 14:55:46 lt9630 kernel: [  857.814366]     MC start:0x40100000, Physical:0x0, size:0x50000000.
Oct 25 14:55:46 lt9630 kernel: [  857.814367]     Mapped heap -- Offset:0x0, size:0x2000000, reference count:6, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814369] mc_node :GART_CACHEABLE, total 3 zones
Oct 25 14:55:46 lt9630 kernel: [  857.814370]     MC start:0x10400000, Physical:0x0, size:0x2fd00000.
Oct 25 14:55:46 lt9630 kernel: [  857.814371]     Mapped heap -- Offset:0xa800000, size:0x700000, reference count:1, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814373]     Mapped heap -- Offset:0x9a00000, size:0xe00000, reference count:2, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814374]     Mapped heap -- Offset:0x8c00000, size:0xe00000, reference count:1, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814376]     Mapped heap -- Offset:0x7e00000, size:0xe00000, reference count:2, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814378]     Mapped heap -- Offset:0x7000000, size:0xe00000, reference count:3, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814379]     Mapped heap -- Offset:0x6200000, size:0xe00000, reference count:2, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814381]     Mapped heap -- Offset:0x5400000, size:0xe00000, reference count:2, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814382]     Mapped heap -- Offset:0x4600000, size:0xe00000, reference count:2, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814384]     Mapped heap -- Offset:0x3800000, size:0xe00000, reference count:5, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814385]     Mapped heap -- Offset:0x2f00000, size:0x900000, reference count:6, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814387]     Mapped heap -- Offset:0x2100000, size:0xe00000, reference count:3, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814389]     Mapped heap -- Offset:0x1700000, size:0xa00000, reference count:4, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814390]     Mapped heap -- Offset:0x1000000, size:0x700000, reference count:12, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814392]     Mapped heap -- Offset:0x200000, size:0xe00000, reference count:5, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814393]     Mapped heap -- Offset:0x0, size:0x200000, reference count:14, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814395]     Mapped heap -- Offset:0xef000, size:0x11000, reference count:1, mapping count:0,
Oct 25 14:55:46 lt9630 kernel: [  857.814398] GRBM : 0xa0003828, SRBM : 0x200006c0 .
Oct 25 14:55:46 lt9630 kernel: [  857.814400] CP_RB_BASE : 0x401000, CP_RB_RPTR : 0x10aa0 , CP_RB_WPTR :0x10aa0.
Oct 25 14:55:46 lt9630 kernel: [  857.814402] CP_IB1_BUFSZ:0x2d8, CP_IB1_BASE_HI:0x0, CP_IB1_BASE_LO:0x4040d000.
Oct 25 14:55:46 lt9630 kernel: [  857.814404] last submit IB buffer -- MC :0x4040d000,phys:0x196e97000.
Oct 25 14:55:46 lt9630 kernel: [  857.814406] Dump the trace queue.
Oct 25 14:55:46 lt9630 kernel: [  857.814407] End of dump

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: fglrx 2:8.881-0ubuntu4
ProcVersionSignature: Ubuntu 3.0.0-12.20-generic 3.0.4
Uname: Linux 3.0.0-12-generic x86_64
NonfreeKernelModules: fglrx
.tmp.unity.support.test.0:
 
ApportVersion: 1.23-0ubuntu3
Architecture: amd64
CompizPlugins: [core,bailer,detection,composite,opengl,compiztoolbox,decor,grid,gnomecompat,resize,place,vpswitch,mousepoll,regex,imgpng,session,snap,move,animation,wall,workarounds,expo,ezoom,staticswitcher,fade,scale,unityshell]
CompositorRunning: None
Date: Tue Oct 25 17:35:28 2011
DistUpgraded: Log time: 2011-10-24 16:45:18.438043
DistroCodename: oneiric
DistroVariant: ubuntu
DkmsStatus:
 fglrx, 8.881, 3.0.0-12-generic, x86_64: installed
 fglrx, 8.892, 3.0.0-12-generic, x86_64: built
GraphicsCard:
 ATI Technologies Inc NI Caicos [AMD RADEON HD 6450] [1002:6779] (prog-if 00 [VGA controller])
   Subsystem: Device [1b0a:909d]
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release amd64 (20110427.1)
JockeyStatus:
 xorg:fglrx_updates - ATI/AMD proprietary FGLRX graphics driver (post-release updates) (Proprietary, Disabled, Not in use)
 xorg:fglrx - ATI/AMD proprietary FGLRX graphics driver (Proprietary, Enabled, In use)
MachineType: Dell Inc. Vostro 260
ProcEnviron:
 LANGUAGE=en_GB:en
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.0.0-12-generic root=UUID=3afabb70-6b7f-438b-a6d0-5c17e1749d8b ro quiet splash vt.handoff=7
SourcePackage: fglrx-installer
UpgradeStatus: Upgraded to oneiric on 2011-10-24 (0 days ago)
dmi.bios.date: 07/27/2011
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A02
dmi.board.name: 0GDG8Y
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 3
dmi.chassis.vendor: Dell Inc.
dmi.chassis.version: 00
dmi.modalias: dmi:bvnDellInc.:bvrA02:bd07/27/2011:svnDellInc.:pnVostro260:pvr00:rvnDellInc.:rn0GDG8Y:rvrA00:cvnDellInc.:ct3:cvr00:
dmi.product.name: Vostro 260
dmi.product.version: 00
dmi.sys.vendor: Dell Inc.
version.compiz: compiz 1:0.9.6+bzr20110929-0ubuntu5
version.fglrx-installer: fglrx-installer N/A
version.ia32-libs: ia32-libs 20090808ubuntu26
version.libdrm2: libdrm2 2.4.26-1ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 7.11-0ubuntu3
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 7.11-0ubuntu3
version.xserver-xorg: xserver-xorg 1:7.6+7ubuntu7
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 2:2.15.901-1ubuntu2
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20110411+8378443-1