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Date:   Fri, 30 Nov 2018 13:03:45 +0100
From:   Oleg Nesterov <oleg@redhat.com>
To:     Dave Martin <Dave.Martin@arm.com>
Cc:     Enke Chen <enkechen@cisco.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
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        "Eric W. Biederman" <ebiederm@xmission.com>,
        Khalid Aziz <khalid.aziz@oracle.com>,
        Kate Stewart <kstewart@linuxfoundation.org>,
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        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Andrew Morton <akpm@linux-foundation.org>,
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        Will Deacon <Will.Deacon@arm.com>,
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        Stefan Strogin <sstrogin@cisco.com>
Subject: Re: [PATCH v5 1/2] kernel/signal: Signal-based pre-coredump
 notification
Message-ID: <20181130120344.GA25998@redhat.com>
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On 11/29, Dave Martin wrote:
>
> SIGCHLD + wait() is immune to this problem for other child status
> notifications (albeit with higher overhead).
>
> Unless I've missed something fundamental, signals simply aren't a
> reliable data transport

Yes. But I hope we are not going to implement WCOREDUMP.

I am not fan of this patch, but at least it is simple.

Oleg.