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From: Andy Lutomirski <luto@amacapital.net>
Date: Mon, 29 Aug 2016 16:55:27 -0700
Message-ID: <CALCETrW1m9ozck-ugX6AKnL7oNA8rvMTjhFGqtVSvKL9BMXMZA@mail.gmail.com>
Subject: Re: [PATCH 1/2] tracing/syscalls: allow multiple syscall numbers per syscall
To: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Linux API <linux-api@vger.kernel.org>, linux-mips@vger.kernel.org,
        Ingo Molnar <mingo@redhat.com>, Steven Rostedt <rostedt@goodmis.org>,
        open list <linux-kernel@vger.kernel.org>
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On Aug 29, 2016 11:30 AM, "Marcin Nowakowski"
<marcin.nowakowski@imgtec.com> wrote:
>
> Syscall metadata makes an assumption that only a single syscall number
> corresponds to a given method. This is true for most archs, but
> can break tracing otherwise.
>
> For MIPS platforms, depending on the choice of supported ABIs, up to 3
> system call numbers can correspond to the same call - depending on which
> ABI the userspace app uses.

MIPS isn't special here.  x86 does the same thing.  Why isn't this a
problem on x86?

Also, you seem to be partially reinventing AUDIT_ARCH here.  Can you
use that and integrate with syscall_get_arch()?

--Andy