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Date:   Wed, 25 Apr 2018 15:22:28 +0200
From:   Oleg Nesterov <oleg@redhat.com>
To:     Andrey Grodzovsky <Andrey.Grodzovsky@amd.com>,
        Michel =?iso-8859-1?Q?D=E4nzer?= <michel@daenzer.net>,
        linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org,
        dri-devel@lists.freedesktop.org, David.Panariti@amd.com,
        ebiederm@xmission.com, Alexander.Deucher@amd.com,
        akpm@linux-foundation.org, Christian.Koenig@amd.com
Subject: Re: [PATCH 2/3] drm/scheduler: Don't call wait_event_killable for
 signaled process.
Message-ID: <20180425132228.GC7592@redhat.com>
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On 04/24, Daniel Vetter wrote:
>
> wait_event_killabel doesn't check for fatal_signal_pending before calling
> schedule, so definitely has a nice race there.

This is fine. See the signal_pending_state() check in __schedule().

And this doesn't differ from wait_event_interruptible(), it too doesn't
check signal_pending(), we rely on schedule() which must not block if the
caller is signalled/killed.

The problem is that it is not clear what should fatal_signal_pending() or
even signal_pending() mean after exit_signals().

Oleg.