Re: X server hung, kernel said "task blocked for >120 secs" (2.6.30)

[Andrew Morton <akpm@linux-foundation.org>]

(cc dri-devel)

On Sun, 14 Jun 2009 21:46:05 -0400
Sanjoy Mahajan <sanjoy@MIT.EDU> wrote:

> I'm running vanilla 2.6.30 on an otherwise Debian 'unstable' system -- a
> TP T60 with Intel graphics and wireless (no tainting).  The X server
> [xorg 1.6.1.901 (1.6.2 RC 1), intel driver 2.7.1] hung in a way that it
> often has with other versions: The mouse cursor moves around as normal,
> but the keyboard or mouse buttons don't do anything.  I used sysrq half
> competently to send TERM and KILL signals and then reboot.
> 
> The log message below was in the /var/log/messages from when the problem
> happened.  Should I report this information to freedesktop.org or is it
> a kernel issue belonging on the bugzilla?
> 
> [228600.676053] INFO: task events/0:9 blocked for more than 120 seconds.
> [228600.676058] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [228600.676061] events/0      D 31efa204     0     9      2
> [228600.676066]  c1bfc040 00000046 f7121a60 31efa204 c0439040 c0436134 c0101f70 f708f0c0
> [228600.676075]  f708f274 00000000 00000000 f7121a8c c1bfc040 00000000 c011d842 c1bfc580
> [228600.676083]  f708f0c0 f708f274 0366353a f626cac0 00000000 c0439040 c02f19c2 c03a8300
> [228600.676090] Call Trace:
> [228600.676099]  [<c0101f70>] ? __switch_to+0xbf/0x140
> [228600.676105]  [<c011d842>] ? pick_next_task_fair+0x80/0x87
> [228600.676111]  [<c02f19c2>] ? __schedule+0x6f2/0x74d
> [228600.676115]  [<c02f1fc4>] ? __mutex_lock_common+0xe1/0x136
> [228600.676120]  [<c02f2028>] ? __mutex_lock_slowpath+0xf/0x11
> [228600.676123]  [<c02f1e78>] ? mutex_lock+0x10/0x1e
> [228600.676127]  [<c02f1e78>] ? mutex_lock+0x10/0x1e
> [228600.676133]  [<c0133e97>] ? queue_delayed_work_on+0x9c/0xa8
> [228600.676150]  [<f8ff74f3>] ? i915_gem_retire_work_handler+0x1c/0x4e [i915]
> [228600.676155]  [<c0133701>] ? worker_thread+0x13d/0x1bf
> [228600.676168]  [<f8ff74d7>] ? i915_gem_retire_work_handler+0x0/0x4e [i915]
> [228600.676174]  [<c01365a6>] ? autoremove_wake_function+0x0/0x2d
> [228600.676178]  [<c01335c4>] ? worker_thread+0x0/0x1bf
> [228600.676182]  [<c01362b6>] ? kthread+0x42/0x67
> [228600.676186]  [<c0136274>] ? kthread+0x0/0x67
> [228600.676190]  [<c0103ab7>] ? kernel_thread_helper+0x7/0x10
> [228611.402991] SysRq : Keyboard mode set to system default

I assume this is a regression?  Since 2.6.29?

Thanks.