Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
MIME-Version: 1.0
References: <1530101255-13988-1-git-send-email-crecklin@redhat.com>
 <CAGXu5jLDULvf-VBhUfBXtSNaSWpq8irgg56LT3nHDft5gZg5Lw@mail.gmail.com>
 <5506a72f-99ac-b47c-4ace-86c43b17b5c5@redhat.com> <CAGXu5jL8XDYE+B=a_TBM2K8F-c3f4Jz6zcm3ggacbPNN2wCtpg@mail.gmail.com>
In-Reply-To: <CAGXu5jL8XDYE+B=a_TBM2K8F-c3f4Jz6zcm3ggacbPNN2wCtpg@mail.gmail.com>
From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Tue, 3 Jul 2018 10:04:40 +0200
Message-ID: <CAMuHMdU89jEp4Oi6RK887P-LxCFNVPMnOpvvC6BEDHWDjNATAw@mail.gmail.com>
Subject: Re: [PATCH v3] add param that allows bootline control of hardened usercopy
To:     Kees Cook <keescook@chromium.org>
Cc:     crecklin@redhat.com, Laura Abbott <labbott@redhat.com>,
        pabeni@redhat.com,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux MM <linux-mm@kvack.org>,
        kernel-hardening@lists.openwall.com,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Hi Kees,

On Mon, Jul 2, 2018 at 8:44 PM Kees Cook <keescook@chromium.org> wrote:
> On Sat, Jun 30, 2018 at 1:43 PM, Christoph von Recklinghausen
> <crecklin@redhat.com> wrote:
> > The last issue I'm chasing is build failures on ARCH=m68k. The error is
> > atomic_read and friends needed by the jump label code not being found.
> > The config has CONFIG_BROKEN_ON_SMP=y, so the jump label calls I added
> > will only be made #ifndef CONFIG_BROKEN_ON_SMP. Do you think that's
> > worth a mention in the blurb that's added to
> > Documentation/admin-guide/kernel-parameters.txt?
>
> Uhm, that's weird -- I think the configs on m68k need fixing then? I
> don't want to have to sprinkle that ifdef in generic code.

config BROKEN_ON_SMP
        bool
        depends on BROKEN || !SMP
        default y

So BROKEN_ON_SMP=y if SMP=n, i.e. not an issue?

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