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From:   Josh Don <joshdon@google.com>
Date:   Mon, 14 Jun 2021 16:36:06 -0700
Message-ID: <CABk29NtA4UxM-XqJ0v+5UOZEfgHTozF5VeqVGpLcR3Ci4z806g@mail.gmail.com>
Subject: Re: [PATCH 18/19] sched: prctl() core-scheduling interface
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Joel Fernandes <joel@joelfernandes.org>,
        "Hyser,Chris" <chris.hyser@oracle.com>,
        Ingo Molnar <mingo@kernel.org>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Valentin Schneider <valentin.schneider@arm.com>,
        Mel Gorman <mgorman@suse.de>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Aubrey Li <aubrey.intel@gmail.com>,
        Xiangling Kong <xiangling@google.com>,
        Benjamin Segall <bsegall@google.com>
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On Thu, Apr 22, 2021 at 5:36 AM Peter Zijlstra <peterz@infradead.org> wrote:
>
> From: Chris Hyser <chris.hyser@oracle.com>
>
> This patch provides support for setting and copying core scheduling
> 'task cookies' between threads (PID), processes (TGID), and process
> groups (PGID).

[snip]

Internally, we have lots of trusted processes that don't have a
security need for coresched cookies. However, these processes could
still decide to create cookies for themselves, which will degrade
machine capacity and performance for other jobs on the machine.

Any thoughts on whether it would be desirable to have the ability to
restrict use of SCHED_CORE_CREATE? Perhaps a new SCHED_CORE capability
would be appropriate?

- Josh