Re: [PATCH 1/7] Freezer: Read PF_BORROWED_MM in a nonracy way

[Linus Torvalds]

On Sat, 12 May 2007, Oleg Nesterov wrote:
> 
> without task_lock() we can see "p->mm != NULL" but not PF_BORROWED_MM.

Let me explain it one more time:
 - shouldn't the *caller* protect this?

Afaik, there's two situations:
 - either things don't change (in which case you don't need locking at 
   all, since things are statically one way or the other)
 - or things change (in which case the caller can't rely on the return 
   value anyway, since they might change *after* you release the lock)
ie what's up? Is there a third case?

		Linus
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