Hello 
I was playing with a light game on the dev version of Ubuntu Precise Pangolin and I've installed this kernel ads suggested to see if a paging bug is fixed but I've gort this new onefollowed by the unable to handle kernel null pointer deference at   null.
I' also observed some xorg overflow.

Jan 10 20:03:36 precious-mandolin kernel: [  653.279926] ------------[ cut here ]------------
Jan 10 20:03:36 precious-mandolin kernel: [  653.280013] WARNING: at /home/apw/COD/linux/lib/iomap.c:43 bad_io_access+0x39/0x40()
Jan 10 20:03:36 precious-mandolin kernel: [  653.280190] Hardware name: K8NF4G-SATA2
Jan 10 20:03:36 precious-mandolin kernel: [  653.280194] Bad IO access at port 0x48 (return inl(port))
Jan 10 20:03:36 precious-mandolin kernel: [  653.280206] Modules linked in: bnep rfcomm bluetooth snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm snd_seq_midi snd_rawmidi ppdev arc4 snd_seq_midi_event rt61pci crc_itu_t rt2x00pci rt2x00lib snd_seq mac80211 snd_timer snd_seq_device snd nouveau soundcore edac_core cfg80211 edac_mce_amd psmouse snd_page_alloc eeprom_93cx6 serio_raw k8temp ttm drm_kms_helper drm i2c_algo_bit nv_tco mxm_wmi i2c_nforce2 wmi video ns558 gameport parport_pc lp parport usbhid hid sata_nv pata_amd forcedeth
Jan 10 20:03:36 precious-mandolin kernel: [  653.280362] Pid: 1406, comm: compiz Not tainted 3.2.0-030200rc7-generic #201112240135
Jan 10 20:03:36 precious-mandolin kernel: [  653.280367] Call Trace:
Jan 10 20:03:36 precious-mandolin kernel: [  653.280411]  [<ffffffff8106731f>] warn_slowpath_common+0x7f/0xc0
Jan 10 20:03:36 precious-mandolin kernel: [  653.280420]  [<ffffffff81067416>] warn_slowpath_fmt+0x46/0x50
Jan 10 20:03:36 precious-mandolin kernel: [  653.280425]  [<ffffffff81321699>] bad_io_access+0x39/0x40
Jan 10 20:03:36 precious-mandolin kernel: [  653.280429]  [<ffffffff81321a9c>] ioread32+0x2c/0x40
Jan 10 20:03:36 precious-mandolin kernel: [  653.280571]  [<ffffffffa01852ed>] nouveau_fence_update+0x10d/0x130 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.280590]  [<ffffffffa0185334>] __nouveau_fence_signalled+0x24/0x30 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.280609]  [<ffffffffa01853a0>] __nouveau_fence_wait+0x60/0x100 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.280629]  [<ffffffffa01861af>] nouveau_fence_sync+0x9f/0x110 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.280650]  [<ffffffffa018676f>] validate_list+0xef/0x380 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.280668]  [<ffffffffa01874bd>] nouveau_gem_pushbuf_validate+0xdd/0x220 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.280688]  [<ffffffffa018791f>] nouveau_gem_ioctl_pushbuf+0x1bf/0x8e0 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.280706]  [<ffffffff8118eae0>] ? __pollwait+0xf0/0xf0
Jan 10 20:03:36 precious-mandolin kernel: [  653.280710]  [<ffffffff8118eae0>] ? __pollwait+0xf0/0xf0
Jan 10 20:03:36 precious-mandolin kernel: [  653.280827]  [<ffffffffa0099573>] drm_ioctl+0x483/0x530 [drm]
Jan 10 20:03:36 precious-mandolin kernel: [  653.280845]  [<ffffffffa0187760>] ? nouveau_gem_ioctl_info+0x90/0x90 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.280864]  [<ffffffff81012896>] ? __switch_to+0x256/0x320
Jan 10 20:03:36 precious-mandolin kernel: [  653.280881]  [<ffffffff810590a3>] ? finish_task_switch+0x53/0x100
Jan 10 20:03:36 precious-mandolin kernel: [  653.280897]  [<ffffffff8118de09>] do_vfs_ioctl+0x99/0x350
Jan 10 20:03:36 precious-mandolin kernel: [  653.280902]  [<ffffffff8118e161>] sys_ioctl+0xa1/0xb0
Jan 10 20:03:36 precious-mandolin kernel: [  653.280926]  [<ffffffff8164f342>] system_call_fastpath+0x16/0x1b
Jan 10 20:03:36 precious-mandolin kernel: [  653.280932] ---[ end trace 175465754119ed48 ]---
Jan 10 20:03:36 precious-mandolin kernel: [  653.285119] BUG: unable to handle kernel NULL pointer dereference at           (null)
Jan 10 20:03:36 precious-mandolin kernel: [  653.285297] IP: [<ffffffffa018524e>] nouveau_fence_update+0x6e/0x130 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.285482] PGD 65923067 PUD 655d5067 PMD 0 
Jan 10 20:03:36 precious-mandolin kernel: [  653.285506] Oops: 0000 [#1] SMP 
Jan 10 20:03:36 precious-mandolin kernel: [  653.285532] CPU 0 
Jan 10 20:03:36 precious-mandolin kernel: [  653.285542] Modules linked in: bnep rfcomm bluetooth snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm snd_seq_midi snd_rawmidi ppdev arc4 snd_seq_midi_event rt61pci crc_itu_t rt2x00pci rt2x00lib snd_seq mac80211 snd_timer snd_seq_device snd nouveau soundcore edac_core cfg80211 edac_mce_amd psmouse snd_page_alloc eeprom_93cx6 serio_raw k8temp ttm drm_kms_helper drm i2c_algo_bit nv_tco mxm_wmi i2c_nforce2 wmi video ns558 gameport parport_pc lp parport usbhid hid sata_nv pata_amd forcedeth
Jan 10 20:03:36 precious-mandolin kernel: [  653.285736] 
Jan 10 20:03:36 precious-mandolin kernel: [  653.285752] Pid: 1406, comm: compiz Tainted: G        W    3.2.0-030200rc7-generic #201112240135          K8NF4G-SATA2/K8NF4G-SATA2
Jan 10 20:03:36 precious-mandolin kernel: [  653.285785] RIP: 0010:[<ffffffffa018524e>]  [<ffffffffa018524e>] nouveau_fence_update+0x6e/0x130 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.285822] RSP: 0018:ffff88006540bb08  EFLAGS: 00010286
Jan 10 20:03:36 precious-mandolin kernel: [  653.285833] RAX: fffffffffffffff0 RBX: ffff880069b008f8 RCX: 0000000000000000
Jan 10 20:03:36 precious-mandolin kernel: [  653.285849] RDX: 0000000000000000 RSI: 0000000000000082 RDI: 0000000000000009
Jan 10 20:03:36 precious-mandolin kernel: [  653.285864] RBP: ffff88006540bb48 R08: 0000000000000000 R09: 0000000000000000
Jan 10 20:03:36 precious-mandolin kernel: [  653.285878] R10: 0000000000000000 R11: 0000000000000001 R12: ffff88004bdfac00
Jan 10 20:03:36 precious-mandolin kernel: [  653.285893] R13: 0000000000000000 R14: ffff880069b00890 R15: ffff880069b00900
Jan 10 20:03:36 precious-mandolin kernel: [  653.285910] FS:  00007f5e288a59c0(0000) GS:ffff88007bc00000(0000) knlGS:0000000000000000
Jan 10 20:03:36 precious-mandolin kernel: [  653.285927] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Jan 10 20:03:36 precious-mandolin kernel: [  653.285939] CR2: 0000000000000000 CR3: 0000000065920000 CR4: 00000000000006f0
Jan 10 20:03:36 precious-mandolin kernel: [  653.285956] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
Jan 10 20:03:36 precious-mandolin kernel: [  653.285973] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Jan 10 20:03:36 precious-mandolin kernel: [  653.285988] Process compiz (pid: 1406, threadinfo ffff88006540a000, task ffff8800659044a0)
Jan 10 20:03:36 precious-mandolin kernel: [  653.286005] Stack:
Jan 10 20:03:36 precious-mandolin kernel: [  653.286012]  ffff880069b00880 0000000000000004 0000000000000000 ffff88004bdfaec0
Jan 10 20:03:36 precious-mandolin kernel: [  653.286039]  ffff88004bdfaec0 0000000000000000 00000000000003e8 ffff8800659044a0
Jan 10 20:03:36 precious-mandolin kernel: [  653.286060]  ffff88006540bb68 ffffffffa0185334 ffff88006540bb88 0000000000000000
Jan 10 20:03:36 precious-mandolin kernel: [  653.286081] Call Trace:
Jan 10 20:03:36 precious-mandolin kernel: [  653.286121]  [<ffffffffa0185334>] __nouveau_fence_signalled+0x24/0x30 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.286154]  [<ffffffffa01853a0>] __nouveau_fence_wait+0x60/0x100 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.286187]  [<ffffffffa01861af>] nouveau_fence_sync+0x9f/0x110 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.286220]  [<ffffffffa018676f>] validate_list+0xef/0x380 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.286248]  [<ffffffffa01874bd>] nouveau_gem_pushbuf_validate+0xdd/0x220 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.286280]  [<ffffffffa018791f>] nouveau_gem_ioctl_pushbuf+0x1bf/0x8e0 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.286318]  [<ffffffff8118eae0>] ? __pollwait+0xf0/0xf0
Jan 10 20:03:36 precious-mandolin kernel: [  653.286331]  [<ffffffff8118eae0>] ? __pollwait+0xf0/0xf0
Jan 10 20:03:36 precious-mandolin kernel: [  653.286460]  [<ffffffffa0099573>] drm_ioctl+0x483/0x530 [drm]
Jan 10 20:03:36 precious-mandolin kernel: [  653.286491]  [<ffffffffa0187760>] ? nouveau_gem_ioctl_info+0x90/0x90 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.286524]  [<ffffffff81012896>] ? __switch_to+0x256/0x320
Jan 10 20:03:36 precious-mandolin kernel: [  653.286554]  [<ffffffff810590a3>] ? finish_task_switch+0x53/0x100
Jan 10 20:03:36 precious-mandolin kernel: [  653.286567]  [<ffffffff8118de09>] do_vfs_ioctl+0x99/0x350
Jan 10 20:03:36 precious-mandolin kernel: [  653.286578]  [<ffffffff8118e161>] sys_ioctl+0xa1/0xb0
Jan 10 20:03:36 precious-mandolin kernel: [  653.286594]  [<ffffffff8164f342>] system_call_fastpath+0x16/0x1b
Jan 10 20:03:36 precious-mandolin kernel: [  653.286604] Code: 8f b8 00 00 00 41 8b 86 88 00 00 00 41 39 86 84 00 00 00 0f 84 8b 00 00 00 49 8b 4e 70 41 89 86 84 00 00 00 48 8d 41 f0 49 39 cf <48> 8b 50 10 74 73 4c 8d 62 f0 eb 1c 66 0f 1f 44 00 00 49 8d 44 
Jan 10 20:03:36 precious-mandolin kernel: [  653.286784] RIP  [<ffffffffa018524e>] nouveau_fence_update+0x6e/0x130 [nouveau]
Jan 10 20:03:36 precious-mandolin kernel: [  653.286813]  RSP <ffff88006540bb08>
Jan 10 20:03:36 precious-mandolin kernel: [  653.286820] CR2: 0000000000000000
Jan 10 20:03:36 precious-mandolin kernel: [  653.286901] [drm] nouveau 0000:00:05.0: Setting dpms mode 3 on vga encoder (output 0)
Jan 10 20:03:36 precious-mandolin kernel: [  653.288063] [drm] nouveau 0000:00:05.0: Setting dpms mode 0 on vga encoder (output 0)
Jan 10 20:03:36 precious-mandolin kernel: [  653.288063] [drm] nouveau 0000:00:05.0: Output VGA-1 is running on CRTC 0 using output B
Jan 10 20:03:36 precious-mandolin kernel: [  653.310100] ---[ end trace 175465754119ed49 ]---
Jan 10 20:04:38 precious-mandolin kernel: [  714.893181] SysRq : Keyboard mode set to system default

I attach the full kern.log to evaluate