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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed, 9 Jun 2021 13:52:07 -0700
Message-ID: <CAHk-=wgXROFSDa6gHei4fNmdU=VppqnBThdCraNpuirriSyKQA@mail.gmail.com>
Subject: Re: [RFC] coredump: Do not interrupt dump for TIF_NOTIFY_SIGNAL
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        io-uring <io-uring@vger.kernel.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Olivier Langlois <olivier@trillion01.com>,
        Jens Axboe <axboe@kernel.dk>,
        "Pavel Begunkov>" <asml.silence@gmail.com>,
        Oleg Nesterov <oleg@redhat.com>
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On Wed, Jun 9, 2021 at 1:48 PM Eric W. Biederman <ebiederm@xmission.com> wrote:
>
> It looks like it would need to be:
>
> static bool dump_interrupted(void)
> {
>         return fatal_signal_pending() || freezing();
> }
>
> As the original implementation of dump_interrupted 528f827ee0bb
> ("coredump: introduce dump_interrupted()") is deliberately allowing the
> freezer to terminate the core dumps to allow for reliable system
> suspend.

Ack. That would seem to be the right conversion to do.

Now, I'm not sure if system suspend really should abort a core dump,
but it's clearly what we have done in the past.

Maybe we'd like to remove that "|| freezing()" at some point, but
that's a separate discussion, I think. At least having it in that form
makes it all very explicit, instead of the current very subtle exact
interaction with the TIF_NOTIFY_SIGNAL bit (that has other meanings).

Hmm?

             Linus