Subject: Re: [PATCH v10 09/12] arch/x86: enable task isolation functionality
To: Andy Lutomirski <luto@amacapital.net>, Kees Cook <keescook@chromium.org>
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CC: Thomas Gleixner <tglx@linutronix.de>, Christoph Lameter <cl@linux.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Viresh Kumar <viresh.kumar@linaro.org>, Ingo Molnar <mingo@kernel.org>,
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        X86 ML <x86@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Peter Zijlstra <peterz@infradead.org>
From: Chris Metcalf <cmetcalf@mellanox.com>
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Date: Wed, 9 Mar 2016 16:05:53 -0500
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On 3/9/2016 3:58 PM, Andy Lutomirski wrote:
>> My preference would be not to have to require all task-isolation users
>> >to also figure out all the complexities of creating BPF programs, so
>> >my intention is to have task isolation automatically generate a BPF
>> >program (just allowing prctl/exit/exit_group and failing everything
>> >else with SIGSYS).  To support having it work this way, I open up
>> >the seccomp stuff a little so that kernel clients can effectively
>> >push/pop a BPF program into seccomp:
> That sounds like a great use case for the new libtaskisolation that
> someone is surely writing:)

Happily, task isolation is so simple an API that all that is needed is a prctl().

... Unless somehow a requirement to inflict a huge blob of eBPF into the kernel
just to use task isolation safely is added, of course :-)

-- 
Chris Metcalf, Mellanox Technologies
http://www.mellanox.com