What do these error messages mean and how to fix it?

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actually I figured out this is an issue of intel video driver:http://lkml.indiana.edu/hypermail/linux/kernel/0902.3/01703.html

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I am using ubuntu 10.0.4 TLS, and this is my main board info: http://www.made-in-china.com/showroom/geshem/product-detailbqfJOksvrXcn/China-Mainboard-ITX-WN45A-D.html

These error messages were from /var/log/messages

Dec 17 09:46:53 my-desktop kernel: [ 1080.890084] i915          D 0000000000000000     0   595      2 0x00000000
Dec 17 09:46:53 my-desktop kernel: [ 1080.890096]  ffff880030257d40 0000000000000046 0000000000015bc0 0000000000015bc0
Dec 17 09:46:53 my-desktop kernel: [ 1080.890107]  ffff880030b53178 ffff880030257fd8 0000000000015bc0 ffff880030b52dc0
Dec 17 09:46:53 my-desktop kernel: [ 1080.890117]  0000000000015bc0 ffff880030257fd8 0000000000015bc0 ffff880030b53178
Dec 17 09:46:53 my-desktop kernel: [ 1080.890127] Call Trace:
Dec 17 09:46:53 my-desktop kernel: [ 1080.890148]  [<ffffffff81542907>] __mutex_lock_slowpath+0xf7/0x180
Dec 17 09:46:53 my-desktop kernel: [ 1080.890161]  [<ffffffff810578b0>] ? finish_task_switch+0x50/0xe0
Dec 17 09:46:53 my-desktop kernel: [ 1080.890169]  [<ffffffff815427eb>] mutex_lock+0x2b/0x50
Dec 17 09:46:53 my-desktop kernel: [ 1080.890207]  [<ffffffffa0110add>] i915_gem_retire_work_handler+0x3d/0xa0 [i915]
Dec 17 09:46:53 my-desktop kernel: [ 1080.890231]  [<ffffffffa0110aa0>] ? i915_gem_retire_work_handler+0x0/0xa0 [i915]
Dec 17 09:46:53 my-desktop kernel: [ 1080.890243]  [<ffffffff8107f9a7>] run_workqueue+0xc7/0x1a0
Dec 17 09:46:53 my-desktop kernel: [ 1080.890252]  [<ffffffff8107fb23>] worker_thread+0xa3/0x110
Dec 17 09:46:53 my-desktop kernel: [ 1080.890261]  [<ffffffff81084570>] ? autoremove_wake_function+0x0/0x40
Dec 17 09:46:53 my-desktop kernel: [ 1080.890270]  [<ffffffff8107fa80>] ? worker_thread+0x0/0x110
Dec 17 09:46:53 my-desktop kernel: [ 1080.890278]  [<ffffffff810841f6>] kthread+0x96/0xa0
Dec 17 09:46:53 my-desktop kernel: [ 1080.890287]  [<ffffffff810131ea>] child_rip+0xa/0x20
Dec 17 09:46:53 my-desktop kernel: [ 1080.890296]  [<ffffffff81084160>] ? kthread+0x0/0xa0
Dec 17 09:46:53 my-desktop kernel: [ 1080.890303]  [<ffffffff810131e0>] ? child_rip+0x0/0x20
Dec 17 10:08:53 my-desktop kernel: [ 2400.890080] i915          D 0000000000000000     0   595      2 0x00000000
Dec 17 10:08:53 my-desktop kernel: [ 2400.890092]  ffff880030257d40 0000000000000046 0000000000015bc0 0000000000015bc0
Dec 17 10:08:53 my-desktop kernel: [ 2400.890103]  ffff880030b53178 ffff880030257fd8 0000000000015bc0 ffff880030b52dc0
Dec 17 10:08:53 my-desktop kernel: [ 2400.890113]  0000000000015bc0 ffff880030257fd8 0000000000015bc0 ffff880030b53178
Dec 17 10:08:53 my-desktop kernel: [ 2400.890122] Call Trace:
Dec 17 10:08:53 my-desktop kernel: [ 2400.890143]  [<ffffffff81542907>] __mutex_lock_slowpath+0xf7/0x180
Dec 17 10:08:53 my-desktop kernel: [ 2400.890156]  [<ffffffff810578b0>] ? finish_task_switch+0x50/0xe0
Dec 17 10:08:53 my-desktop kernel: [ 2400.890164]  [<ffffffff815427eb>] mutex_lock+0x2b/0x50
Dec 17 10:08:53 my-desktop kernel: [ 2400.890202]  [<ffffffffa0110add>] i915_gem_retire_work_handler+0x3d/0xa0 [i915]
Dec 17 10:08:53 my-desktop kernel: [ 2400.890226]  [<ffffffffa0110aa0>] ? i915_gem_retire_work_handler+0x0/0xa0 [i915]
Dec 17 10:08:53 my-desktop kernel: [ 2400.890237]  [<ffffffff8107f9a7>] run_workqueue+0xc7/0x1a0
Dec 17 10:08:53 my-desktop kernel: [ 2400.890246]  [<ffffffff8107fb23>] worker_thread+0xa3/0x110
Dec 17 10:08:53 my-desktop kernel: [ 2400.890256]  [<ffffffff81084570>] ? autoremove_wake_function+0x0/0x40
Dec 17 10:08:53 my-desktop kernel: [ 2400.890265]  [<ffffffff8107fa80>] ? worker_thread+0x0/0x110
Dec 17 10:08:53 my-desktop kernel: [ 2400.890273]  [<ffffffff810841f6>] kthread+0x96/0xa0
Dec 17 10:08:53 my-desktop kernel: [ 2400.890283]  [<ffffffff810131ea>] child_rip+0xa/0x20
Dec 17 10:08:53 my-desktop kernel: [ 2400.890291]  [<ffffffff81084160>] ? kthread+0x0/0xa0

the following are from /var/log/kern.log

Dec 17 09:44:53 pujia-desktop kernel: [  960.890068] INFO: task i915:595 blocked for more than 120 seconds.
Dec 17 09:44:53 pujia-desktop kernel: [  960.890076] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Dec 17 09:44:53 pujia-desktop kernel: [  960.890084] i915          D 0000000000000000     0   595      2 0x00000000
Dec 17 09:44:53 pujia-desktop kernel: [  960.890095]  ffff880030257d40 0000000000000046 0000000000015bc0 0000000000015bc0
Dec 17 09:44:53 pujia-desktop kernel: [  960.890106]  ffff880030b53178 ffff880030257fd8 0000000000015bc0 ffff880030b52dc0
Dec 17 09:44:53 pujia-desktop kernel: [  960.890116]  0000000000015bc0 ffff880030257fd8 0000000000015bc0 ffff880030b53178
Dec 17 09:44:53 pujia-desktop kernel: [  960.890126] Call Trace:
Dec 17 09:44:53 pujia-desktop kernel: [  960.890146]  [<ffffffff81542907>] __mutex_lock_slowpath+0xf7/0x180
Dec 17 09:44:53 pujia-desktop kernel: [  960.890159]  [<ffffffff810578b0>] ? finish_task_switch+0x50/0xe0
Dec 17 09:44:53 pujia-desktop kernel: [  960.890168]  [<ffffffff815427eb>] mutex_lock+0x2b/0x50
Dec 17 09:44:53 pujia-desktop kernel: [  960.890206]  [<ffffffffa0110add>] i915_gem_retire_work_handler+0x3d/0xa0 [i915]
Dec 17 09:44:53 pujia-desktop kernel: [  960.890230]  [<ffffffffa0110aa0>] ? i915_gem_retire_work_handler+0x0/0xa0 [i915]
Dec 17 09:44:53 pujia-desktop kernel: [  960.890241]  [<ffffffff8107f9a7>] run_workqueue+0xc7/0x1a0
Dec 17 09:44:53 pujia-desktop kernel: [  960.890250]  [<ffffffff8107fb23>] worker_thread+0xa3/0x110
Dec 17 09:44:53 pujia-desktop kernel: [  960.890259]  [<ffffffff81084570>] ? autoremove_wake_function+0x0/0x40
Dec 17 09:44:53 pujia-desktop kernel: [  960.890269]  [<ffffffff8107fa80>] ? worker_thread+0x0/0x110
Dec 17 09:44:53 pujia-desktop kernel: [  960.890276]  [<ffffffff810841f6>] kthread+0x96/0xa0
Dec 17 09:44:53 pujia-desktop kernel: [  960.890286]  [<ffffffff810131ea>] child_rip+0xa/0x20
Dec 17 09:44:53 pujia-desktop kernel: [  960.890294]  [<ffffffff81084160>] ? kthread+0x0/0xa0
Dec 17 09:44:53 pujia-desktop kernel: [  960.890302]  [<ffffffff810131e0>] ? child_rip+0x0/0x20
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890068] INFO: task i915:595 blocked for more than 120 seconds.
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890077] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890084] i915          D 0000000000000000     0   595      2 0x00000000
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890096]  ffff880030257d40 0000000000000046 0000000000015bc0 0000000000015bc0
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890107]  ffff880030b53178 ffff880030257fd8 0000000000015bc0 ffff880030b52dc0
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890117]  0000000000015bc0 ffff880030257fd8 0000000000015bc0 ffff880030b53178
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890127] Call Trace:
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890148]  [<ffffffff81542907>] __mutex_lock_slowpath+0xf7/0x180
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890161]  [<ffffffff810578b0>] ? finish_task_switch+0x50/0xe0
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890169]  [<ffffffff815427eb>] mutex_lock+0x2b/0x50
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890207]  [<ffffffffa0110add>] i915_gem_retire_work_handler+0x3d/0xa0 [i915]
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890231]  [<ffffffffa0110aa0>] ? i915_gem_retire_work_handler+0x0/0xa0 [i915]
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890243]  [<ffffffff8107f9a7>] run_workqueue+0xc7/0x1a0
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890252]  [<ffffffff8107fb23>] worker_thread+0xa3/0x110
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890261]  [<ffffffff81084570>] ? autoremove_wake_function+0x0/0x40
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890270]  [<ffffffff8107fa80>] ? worker_thread+0x0/0x110
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890278]  [<ffffffff810841f6>] kthread+0x96/0xa0
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890287]  [<ffffffff810131ea>] child_rip+0xa/0x20
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890296]  [<ffffffff81084160>] ? kthread+0x0/0xa0
Dec 17 09:46:53 pujia-desktop kernel: [ 1080.890303]  [<ffffffff810131e0>] ? child_rip+0x0/0x20

https://bugs.freedesktop.org/show_bug.cgi?id=28805

Try to upgrade to kernel 2.6.36 and see if it works.