BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<c01bb811>] put_page+0x11/0x100
*pde = 7f2a6067 
Oops: 0000 [#1] SMP 
last sysfs file: /sys/devices/LNXSYSTM:00/device:00/PNP0C0A:00/power_supply/C1C8/voltage_now
Modules linked in: lib80211_crypt_tkip wl(P) lib80211 binfmt_misc ppdev lp parport snd_hda_codec_analog snd_hda_intel snd_hda_codec snd_hwdep snd_pcm_oss snd_mixer_oss snd_pcm bridge snd_seq_dummy stp snd_seq_oss bnep snd_seq_midi snd_rawmidi iptable_filter ip_tables snd_seq_midi_event joydev x_tables snd_seq snd_timer hp_accel uvcvideo mac80211 snd_seq_device lis3lv02d videodev v4l1_compat input_polldev snd btusb dm_crypt cfg80211 psmouse soundcore snd_page_alloc serio_raw led_class squashfs aufs nls_iso8859_1 nls_cp437 vfat fat dm_raid45 xor fbcon tileblit font bitblit softcursor i915 usb_storage sky2 drm i2c_algo_bit intel_agp agpgart video output [last unloaded: ssb]

Pid: 3369, comm: Xorg Tainted: P           (2.6.31-14-generic #48-Ubuntu) HP 2140
EIP: 0060:[<c01bb811>] EFLAGS: 00013286 CPU: 1
EIP is at put_page+0x11/0x100
EAX: 00000000 EBX: 00000000 ECX: 00000000 EDX: f630c3a0
ESI: f65e8480 EDI: 00000000 EBP: f6633da4 ESP: f6633d90
 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Process Xorg (pid: 3369, ti=f6632000 task=f61925b0 task.ti=f6632000)
Stack:
 f6633d9c c050c37a 00000001 f65e8480 00000000 f6633db4 c0493267 f65e8480
<0> c050c94a f6633dc0 c0492da2 f65e8480 f6633dd4 c0492e9b f65e8480 0000028c
<0> 00000000 f6633e4c c050c94a c057d960 f6633e14 f64edae0 ffffffa1 00000001
Call Trace:
 [<c050c37a>] ? unix_write_space+0x3a/0x70
 [<c0493267>] ? skb_release_data+0x87/0xa0
 [<c050c94a>] ? unix_stream_recvmsg+0x1aa/0x440
 [<c0492da2>] ? __kfree_skb+0x12/0x90
 [<c0492e9b>] ? kfree_skb+0x3b/0x80
 [<c050c94a>] ? unix_stream_recvmsg+0x1aa/0x440
 [<c0486a30>] ? apparmor_socket_recvmsg+0x10/0x20
 [<c048ecdc>] ? sock_aio_read+0x11c/0x130
 [<f81466c0>] ? drm_ioctl+0x180/0x360 [drm]
 [<c01e72bc>] ? do_sync_read+0xbc/0x100
 [<c015c280>] ? autoremove_wake_function+0x0/0x40
 [<c02c7acf>] ? security_file_permission+0xf/0x20
 [<c01e735f>] ? rw_verify_area+0x5f/0xe0
 [<c0570ac7>] ? unlock_kernel+0x27/0x30
 [<c01e799a>] ? vfs_read+0x17a/0x190
 [<c01e7ecd>] ? sys_read+0x3d/0x70
 [<c010336c>] ? syscall_call+0x7/0xb
Code: fe ff ff f0 80 23 fb eb dc 90 55 b8 e0 be 1b c0 89 e5 e8 13 d8 f9 ff 5d c3 90 55 89 e5 83 ec 14 89 5d f4 89 c3 89 75 f8 89 7d fc <66> f7 00 00 c0 0f 85 cc 00 00 00 f0 ff 48 04 0f 94 c0 84 c0 74 
EIP: [<c01bb811>] put_page+0x11/0x100 SS:ESP 0068:f6633d90
CR2: 0000000000000000
---[ end trace 4e2489796e0d52e0 ]---