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From:   Arnd Bergmann <arnd@arndb.de>
Date:   Wed, 29 May 2019 15:41:31 +0200
Message-ID: <CAK8P3a0zj126XSGjMbiDJDkY8sF+6JNWH0VsJEUAga6OGHV0vg@mail.gmail.com>
Subject: Re: [PATCH] binfmt_flat: make load_flat_shared_library() work
To:     Greg Ungerer <gregungerer00@gmail.com>
Cc:     Jann Horn <jannh@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        kernel list <linux-kernel@vger.kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Nicolas Pitre <nicolas.pitre@linaro.org>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        "Linux/m68k" <linux-m68k@vger.kernel.org>,
        Russell King <linux@armlinux.org.uk>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Sergei Poselenov <sposelenov@emcraft.com>
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On Wed, May 29, 2019 at 2:29 PM Greg Ungerer <gregungerer00@gmail.com> wrote:
> On 29/5/19 10:05 pm, Arnd Bergmann wrote:
> > On Tue, May 28, 2019 at 12:56 PM Greg Ungerer <gerg@linux-m68k.org> wrote:
> >> On 27/5/19 11:38 pm, Jann Horn wrote:
> >>> On Sat, May 25, 2019 at 11:43 PM Andrew Morton
> >>> <akpm@linux-foundation.org> wrote:
> >>> Maybe... but I didn't want to rip it out without having one of the
> >>> maintainers confirm that this really isn't likely to be used anymore.
> >>
> >> I have not used shared libraries on m68k non-mmu setups for
> >> a very long time. At least 10 years I would think.
> >
> > I think Emcraft have a significant customer base running ARM NOMMU
> > Linux, I wonder whether they would have run into this (adding
> > Sergei to Cc).
> > My suspicion is that they use only binfmt-elf-fdpic, not binfmt-flat.
> >
> > The only architectures I see that enable binfmt-flat are sh, xtensa
> > and h8300, but only arch/sh uses CONFIG_BINFMT_SHARED_FLAT
>
> m68k uses enables it too. It is the only binary format supported
> when running no-mmu on m68k. (You can use it with MMU enabled too
> if you really want too).

My mistake, I meant to write 'the only architectures /other than m68k/",
which you had already mentioned above.

    Arnd