Re: Hmm.. "notify_parent()".

From: Philipp Rumpf (
Date: Mon Aug 28 2000 - 21:53:43 EST

On Mon, Aug 28, 2000 at 01:54:07PM -0700, Linus Torvalds wrote:
> "notify_parent()" uses p->p_pptr without any locking. As far as I can
> tell, that is wrong. It looks like it should have a read-lock on the
> tasklist_lock in order to not be racy (perhaps the parent does an exit on
> another CPU at just this moment), but it gets slightly ugly because it is
> already called occasionally from contexts that already have it, and in
> other places from contexts that do _not_ have it.

Just so no one else bothers checking this, the trick we use in sys_getppid()
doesn't work. I'm also not convinced it's worth it to keep that one - it is
rather subtle and we end up doing a memory barrier anyway.

        Philipp Rumpf
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