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Date: Thu, 8 Mar 2012 17:08:43 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: "Dmitry ADAMUSHKA (EXT)" <dmitry.adamushka_ext@softathome.com>
Cc: Ingo Molnar <mingo@elte.hu>, Ralf Baechle <ralf@linux-mips.org>,
        wouter cloetens <wouter.cloetens@softathome.com>,
        linux-kernel@vger.kernel.org,
        Dmitry Adamushko <dmitry.adamushko@gmail.com>
Subject: Re: 'khelper' (child) is stuck in endless loop: do_signal() and
	!user_mode(regs)
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On 03/08, Dmitry ADAMUSHKA (EXT) wrote:
>
> And to simplify a real-life test case: it's enough for khelper's child task,
> while it's running in ____call_usermodehelper(), to receive SIGKILL.
> In this case, do_execve_common() will fail - there are a number of
> fatal_signal_pending(current) checks in there.

Actually there is no difference, SIGUSR1 equally kills the task and
makes fatal_signal_pending() true. The handler is SIG_DFL after
flush_signal_handlers(), complete_signal() adds SIGKILL implicitely.

Not that this actually matters.

Oleg.