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From:   Florian Weimer <fweimer@redhat.com>
To:     Christian Brauner <christian@brauner.io>
Cc:     linux-kernel@vger.kernel.org, linux-api@vger.kernel.org,
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        keescook@chromium.org, tglx@linutronix.de, x86@kernel.org
Subject: Re: [PATCH v4] signal: add taskfd_send_signal() syscall
References: <20181206121858.12215-1-christian@brauner.io>
Date:   Thu, 06 Dec 2018 13:30:19 +0100
In-Reply-To: <20181206121858.12215-1-christian@brauner.io> (Christian
        Brauner's message of "Thu, 6 Dec 2018 13:18:58 +0100")
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* Christian Brauner:

> /* zombies */
> Zombies can be signaled just as any other process. No special error will be
> reported since a zombie state is an unreliable state (cf. [3]).

I still disagree with this analysis.  If I know that the target process
is still alive, and it is not, this is a persistent error condition
which can be reliably reported.  Given that someone might send SIGKILL
to the process behind my back, detecting this error condition could be
useful.

Rest looks good to me (with the usual caveats).

Thanks,
Florian