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Date: Sat, 16 Feb 2013 18:06:44 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Mandeep Singh Baines <msb@chromium.org>
Cc: linux-kernel@vger.kernel.org, Tejun Heo <tj@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        "Rafael J. Wysocki" <rjw@sisk.pl>, Ingo Molnar <mingo@redhat.com>
Subject: Re: [PATCH 4/5] freezer: clear fake signal on exit from
	__refrigerator
Message-ID: <20130216170644.GD4910@redhat.com>
References: <1361008406-2307-1-git-send-email-msb@chromium.org> <1361008406-2307-4-git-send-email-msb@chromium.org>
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On 02/16, Mandeep Singh Baines wrote:
>
> --- a/kernel/freezer.c
> +++ b/kernel/freezer.c
> @@ -81,6 +81,9 @@ bool __refrigerator(bool check_kthr_stop)
>  	 */
>  	set_current_state(save);
>
> +	/* Clear fake signal from freeze_task(). */
> +	recalc_sigpending();

NACK. We can't do this lockless.

And I am not sure we should reinstantiate it here.

The coredumping is "special". It is not a kernel thread, but it does
a lot of in-kernel activity and never returns to user-mode. If it play
games with the freezer, perhaps it should take care itself...

Tejun?

Oleg.