Re: [PATCH] Fix deadlock in __create_workqueue

[Srivatsa Vaddagiri]

On Fri, Apr 30, 2004 at 07:19:01PM -0700, Andrew Morton wrote:
> Yes, the logic in worker_thread() is a bit dorky, but I
> don't believe that there is a race in there.

worker_thread examines kthread_should_stop() while its state
is TASK_RUNNING, after which it sets its state to TASK_INTERRUPTIBLE.
If kthread_stop were to come after kthread_should_stop and before
worker_thread has set its state to TASK_INTERRUPTIBLE (which is possible
because of a CPU going dead), wouldn't kthread_stop block forever? 
Note that in case of CPU going dead, it is possible that a worker
thread bound to the dead cpu continues executing on a different cpu 
before it is killed in CPU_DEAD processing.

Am I missing something here?

-- 


Thanks and Regards,
Srivatsa Vaddagiri,
Linux Technology Center,
IBM Software Labs,
Bangalore, INDIA - 560017
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