From: Andy Lutomirski <luto@kernel.org>
To: Daniel Colascione <dancol@google.com>
Cc: Tim Murray <timmurray@google.com>,
Suren Baghdasaryan <surenb@google.com>,
LKML <linux-kernel@vger.kernel.org>,
Linux API <linux-api@vger.kernel.org>
Subject: Re: [RFC] Add critical process prctl
Date: Tue, 10 Sep 2019 09:56:53 -0700 [thread overview]
Message-ID: <CALCETrU2Wycgdfo8vLZQUnx1J9ro=6ddSkP37BhsfBkKL1mbMA@mail.gmail.com> (raw)
In-Reply-To: <20190905005313.126823-1-dancol@google.com>
On Wed, Sep 4, 2019 at 5:53 PM Daniel Colascione <dancol@google.com> wrote:
>
> A task with CAP_SYS_ADMIN can mark itself PR_SET_TASK_CRITICAL,
> meaning that if the task ever exits, the kernel panics. This facility
> is intended for use by low-level core system processes that cannot
> gracefully restart without a reboot. This prctl allows these processes
> to ensure that the system restarts when they die regardless of whether
> the rest of userspace is operational.
The kind of panic produced by init crashing is awful -- logs don't get
written, etc. I'm wondering if you would be better off with a new
watchdog-like device that, when closed, kills the system in a
configurable way (e.g. after a certain amount of time, while still
logging something and having a decent chance of getting the logs
written out.) This could plausibly even be an extension to the
existing /dev/watchdog API.
--Andy
next prev parent reply other threads:[~2019-09-10 16:56 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-05 0:53 [RFC] Add critical process prctl Daniel Colascione
2019-09-10 16:56 ` Andy Lutomirski [this message]
2019-09-10 17:42 ` Daniel Colascione
2019-09-10 18:15 ` Andy Lutomirski
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