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Date:   Wed, 25 Apr 2018 15:55:52 +0200
From:   Oleg Nesterov <oleg@redhat.com>
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     Andrey Grodzovsky <Andrey.Grodzovsky@amd.com>,
        linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org,
        Alexander.Deucher@amd.com, Christian.Koenig@amd.com,
        David.Panariti@amd.com, akpm@linux-foundation.org
Subject: Re: [PATCH 2/3] drm/scheduler: Don't call wait_event_killable for
 signaled process.
Message-ID: <20180425135552.GD7592@redhat.com>
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On 04/24, Eric W. Biederman wrote:
>
> Let me respectfully suggest that the wait_event_killable on that code
> path is wrong.

I tend to agree even if I don't know this code.

But if it can be called from f_op->release() then any usage of "current" or
signals looks suspicious. Simply because "current" can be completely irrelevant
task which does the last fput(), say, cat /proc/pid/fdinfo/... or even a kernel
thread.

Oleg.