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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Mon, 10 Jan 2022 16:26:57 +0100
Message-ID: <CAMuHMdWsNBjOJh0QEx9sppA9x3WoL8H2icqukNqECFhOPremjw@mail.gmail.com>
Subject: Re: [PATCH 08/17] ptrace/m68k: Stop open coding ptrace_report_syscall
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux-Arch <linux-arch@vger.kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Oleg Nesterov <oleg@redhat.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Kees Cook <keescook@chromium.org>,
        Linux API <linux-api@vger.kernel.org>
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On Mon, Jan 3, 2022 at 10:33 PM Eric W. Biederman <ebiederm@xmission.com> wrote:
> The generic function ptrace_report_syscall does a little more
> than syscall_trace on m68k.  The function ptrace_report_syscall
> stops early if PT_TRACED is not set, it sets ptrace_message,
> and returns the result of fatal_signal_pending.
>
> Setting ptrace_message to a passed in value of 0 is effectively not
> setting ptrace_message, making that additional work a noop.
>
> Returning the result of fatal_signal_pending and letting the caller
> ignore the result becomes a noop in this change.
>
> When a process is ptraced, the flag PT_PTRACED is always set in
> current->ptrace.  Testing for PT_PTRACED in ptrace_report_syscall is
> just an optimization to fail early if the process is not ptraced.
> Later on in ptrace_notify, ptrace_stop will test current->ptrace under
> tasklist_lock and skip performing any work if the task is not ptraced.
>
> Cc: Geert Uytterhoeven <geert@linux-m68k.org>
> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

As this depends on the removal of a parameter from
ptrace_report_syscall() earlier in this series:
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds