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From: Dmitry Vyukov <dvyukov@google.com>
Date: Mon, 21 Nov 2016 16:17:43 +0100
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Subject: Re: Formal description of system call interface
To: Andy Lutomirski <luto@amacapital.net>
Cc: Linux API <linux-api@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Michael Kerrisk <mtk.manpages@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Sasha Levin <levinsasha928@gmail.com>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>, scientist@fb.com,
        Steven Rostedt <rostedt@goodmis.org>, Arnd Bergmann <arnd@arndb.de>,
        "Carlos O'Donell" <carlos@redhat.com>,
        syzkaller <syzkaller@googlegroups.com>,
        Kostya Serebryany <kcc@google.com>, Mike Frysinger <vapier@google.com>,
        Dave Jones <davej@codemonkey.org.uk>,
        Tavis Ormandy <taviso@google.com>
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On Fri, Nov 11, 2016 at 6:10 PM, Andy Lutomirski <luto@amacapital.net> wrote:
> On Sun, Nov 6, 2016 at 2:39 PM, Dmitry Vyukov <dvyukov@google.com> wrote:
>> Hello,
>>
>> This is notes from the discussion we had at Linux Plumbers this week
>> regarding providing a formal description of system calls (user API).
>>
>> The idea come up in the context of syzkaller, syscall fuzzer, which
>> has descriptions for 1000+ syscalls mostly concentrating on types of
>> arguments and return values. However, problems are that a small group
>> of people can't write descriptions for all syscalls; can't keep them
>> up-to-date and doesn't have necessary domain expertise to do correct
>> descriptions in some cases.
>>
>> We identified a surprisingly large number of potential users for such
>> descriptions:
>
> Let me add one more: consolidation of all the incompatible arch
> syscall tables.  A sufficiently descriptive format should be parseable
> at build time to generate the syscall tables.


Hi Andy,

What exactly info do we need for this?

Anything that just requires a bit of info per syscall looks like the
lowest hanging fruit
(as compared to info per every ioctl discrimination, and complete args
description).