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From: Roland McGrath <roland@redhat.com>
To: Oleg Nesterov <oleg@redhat.com>
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Cc: Andrew Morton <akpm@linux-foundation.org>,
       Linus Torvalds <torvalds@linux-foundation.org>,
       Alan Cox <alan@lxorguk.ukuu.org.uk>,
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       Vitaly Mayatskikh <vmayatsk@redhat.com>, stable@kernel.org,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] copy_process: fix CLONE_PARENT && ->exit_signal
	interaction
In-Reply-To: Oleg Nesterov's message of  Wednesday, 25 February 2009 20:48:51 +0100 <20090225194851.GA9139@redhat.com>
References: <20090225190211.GA7445@redhat.com>
	<20090225193927.1ED25FC3DA@magilla.sf.frob.com>
	<20090225194851.GA9139@redhat.com>
X-Windows: putting new limits on productivity.
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Date: Wed, 25 Feb 2009 11:54:24 -0800 (PST)
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> The task T has ->exit_signal != SIGCHLD, say, SIGHUP. It does
> clone(CLONE_PARENT), copy_process() sets ->exit_signal = SIGHUP.
> 
> T->parent exits, T is re-parented to /sbin/init, and its ->exit_signal
> is changed to SIGCHLD.

I see.  It's tempting to call this a reason to just use SIGCHLD instead of
current->group_leader->exit_signal.  Of course, this all really begs the
question of who uses the case and what they want.


Thanks,
Roland