While booting today's next tree on a powerpc box [ power 6 blade]
observed the following :

khelper used greatest stack depth: 10176 bytes left

=====================================
[ BUG: lock held at task exit time! ]
-------------------------------------
khelper/21 is exiting with locks still held!
2 locks held by khelper/21:
 #0:  (rcu_read_lock){.+.+.+}, at: [<c0000000001382fc>] 
.check_unsafe_exec+0x44/0x148
 #1:  (rcu_read_lock){.+.+.+}, at: [<c000000000138368>] 
.check_unsafe_exec+0xb0/0x148

stack backtrace:
Call Trace:
[c000000044483cf0] [c000000000011a54] .show_stack+0x6c/0x16c (unreliable)
[c000000044483da0] [c00000000009ae14] .debug_check_no_locks_held+0x98/0xb4
[c000000044483e20] [c000000000073b1c] .do_exit+0x758/0x7b0
[c000000044483f00] [c0000000000853d8] .____call_usermodehelper+0x170/0x174
[c000000044483f90] [c00000000002bd8c] .kernel_thread+0x54/0x70
net_namespace: 2000 bytes

Complete dmesg attached. Let me know if you need any other info. I will 
try yesterday's next
tree to check if this problem can be recreated.

Thanks
-Sachin

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Sachin Sant
IBM Linux Technology Center
India Systems and Technology Labs
Bangalore, India
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