Re: [PATCH] kernel/kthread.c: need spin_lock_irq() for 'worker'before main looping, since it can "WARN_ON(worker->task)".

[Thomas Gleixner]

On Wed, 19 Jun 2013, Chen Gang wrote:

> 
> Since "WARN_ON(worker->task)", we can not assume that 'worker->task'
> will be NULL before set 'current' to it.

It better is NULL and all that WARN_ON does is to verify that.
 
> So need let 'worker' lock protected too, just like it already lock
> protected all time in main looping.

No. That's pointless. This happens when the new worker starts up and
there is nothing which can modify worker->task at this point.
 
Thanks,

	tglx
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