Comment 39 for bug 451518

Am seeing this on a Dell Optiplex 980 under karmic:

00:02.0 VGA compatible controller: Intel Corporation Clarkdale Integrated Graphics Controller (rev 02)

[ 838.848500] INFO: task i915/3:428 blocked for more than 120 seconds.
[ 838.848506] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 838.848510] i915/3 D ffffffff815eb720 0 428 2 0x00000000
[ 838.848517] ffff88011046bda0 0000000000000046 0000000000000000 00000000ffffffff
[ 838.848524] ffff88011046bd30 ffffffff8104af6b ffff88010dce2d98 000000010000a007
[ 838.848529] ffff88010dce3110 000000000000f6e8 0000000000015580 ffff88010dce3110
[ 838.848535] Call Trace:
[ 838.848547] [<ffffffff8104af6b>] ? dequeue_entity+0x1b/0x240
[ 838.848555] [<ffffffff815d3fd7>] __mutex_lock_slowpath+0xd7/0x160
[ 838.848560] [<ffffffff815d3ed6>] mutex_lock+0x26/0x50
[ 838.848589] [<ffffffffa00b8398>] i915_gem_retire_work_handler+0x38/0x90 [i915]
[ 838.848608] [<ffffffffa00b8360>] ? i915_gem_retire_work_handler+0x0/0x90 [i915]
[ 838.848615] [<ffffffff8106ca55>] worker_thread+0x165/0x290
[ 838.848621] [<ffffffff81071cb0>] ? autoremove_wake_function+0x0/0x40
[ 838.848626] [<ffffffff8106c8f0>] ? worker_thread+0x0/0x290
[ 838.848631] [<ffffffff810718c6>] kthread+0xa6/0xb0
[ 838.848637] [<ffffffff81012f8a>] child_rip+0xa/0x20
[ 838.848642] [<ffffffff81071820>] ? kthread+0x0/0xb0
[ 838.848646] [<ffffffff81012f80>] ? child_rip+0x0/0x20

May be related: saw several nfs timeout errors in the log at around the same time.