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From:   YiFei Zhu <zhuyifei1999@gmail.com>
Date:   Fri, 9 Oct 2020 13:32:26 -0500
Message-ID: <CABqSeAS0WdkLHGMg3TRKkzsUE=JJYwY4iuBgYpdp-kLd9ASOfg@mail.gmail.com>
Subject: Re: [PATCH v4 seccomp 3/5] x86: Enable seccomp architecture tracking
To:     Andy Lutomirski <luto@amacapital.net>
Cc:     Linux Containers <containers@lists.linux-foundation.org>,
        YiFei Zhu <yifeifz2@illinois.edu>, bpf <bpf@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Aleksa Sarai <cyphar@cyphar.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        David Laight <David.Laight@aculab.com>,
        Dimitrios Skarlatos <dskarlat@cs.cmu.edu>,
        Giuseppe Scrivano <gscrivan@redhat.com>,
        Hubertus Franke <frankeh@us.ibm.com>,
        Jack Chen <jianyan2@illinois.edu>,
        Jann Horn <jannh@google.com>,
        Josep Torrellas <torrella@illinois.edu>,
        Kees Cook <keescook@chromium.org>,
        Tianyin Xu <tyxu@illinois.edu>,
        Tobin Feldman-Fitzthum <tobin@ibm.com>,
        Tycho Andersen <tycho@tycho.pizza>,
        Valentin Rothberg <vrothber@redhat.com>,
        Will Drewry <wad@chromium.org>
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On Fri, Oct 9, 2020 at 12:25 PM Andy Lutomirski <luto@amacapital.net> wrote:
> Is the idea that any syscall that's out of range for this (e.g. all of
> the x32 syscalls) is unoptimized?  I'm okay with this, but I think it
> could use a comment.

Yes, any syscall number that is out of range is unoptimized. Where do
you think I should put a comment? seccomp_cache_check_allow_bitmap
above `if (unlikely(syscall_nr < 0 || syscall_nr >= bitmap_size))`,
with something like "any syscall number out of range is unoptimized"?

YiFei Zhu