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Date: Thu, 9 Sep 2010 22:39:20 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Roland McGrath <roland@redhat.com>, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] exec: don't turn PF_KTHREAD off when command not found
Message-ID: <20100909203920.GA3057@redhat.com>
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On 09/09, KOSAKI Motohiro wrote:
>
> I guess this is only theorical issue because now any kthread don't
> call do_execve() directly.

Yes, I think that kthread should always exit if exec fails.
Otherwise we can "trust" the thread, just suppose that exec fails
after exec_mmap() succeeds.

But,

> but anyway fixing would be better.

Agreed. It looks better if we clear PF_KTHREAD after the point-of-no-return,
and the patch saves one ->flags modification.

Oleg.