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Date: Sun, 14 Dec 2003 14:32:55 -0800 (PST)
From: Linus Torvalds <torvalds@osdl.org>
To: Ingo Molnar <mingo@elte.hu>
cc: Petr Vandrovec <vandrove@vc.cvut.cz>,
       Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@zip.com.au>, Roland McGrath <roland@redhat.com>
Subject: Re: [patch] Re: Problem with exiting threads under NPTL
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On Sun, 14 Dec 2003, Ingo Molnar wrote:
>
> are you sure this can happen? eligible_child() does this:

Interesting. That code should have been enough, but we've later on added
extra code into wait_task_zombie to check _exactly_ the same case because
we saw problems.

Hmm.. Maybe that was to protect against concurrent wait4()'ers (which can
happen - the wait case only takes the read lock). Threads can wait for
each others children, after all.

		Linus