RE: [PATCH] binfmt_flat: Remove shared library support

From: Patrice CHOTARD <patrice.chotard@st.com>
To: Arnd Bergmann <arnd@arndb.de>, Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@linux-m68k.org>,
	"Eric W. Biederman" <ebiederm@xmission.com>,
	Kees Cook <keescook@chromium.org>,
	Niklas Cassel <Niklas.Cassel@wdc.com>,
	Damien Le Moal <damien.lemoal@opensource.wdc.com>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	Paul Walmsley <paul.walmsley@sifive.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
	Mike Frysinger <vapier@gentoo.org>,
	"stable@vger.kernel.org" <stable@vger.kernel.org>,
	"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
	"linux-mm@kvack.org" <linux-mm@kvack.org>,
	"linux-riscv@lists.infradead.org"
	<linux-riscv@lists.infradead.org>,
	Linux-Arch <linux-arch@vger.kernel.org>,
	linux-m68k <linux-m68k@lists.linux-m68k.org>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>,
	Linux-sh list <linux-sh@vger.kernel.org>,
	Yoshinori Sato <ysato@users.sourceforge.jp>,
	Rich Felker <dalias@libc.org>,
	Sudeep Holla <sudeep.holla@arm.com>,
	Vladimir Murzin <vladimir.murzin@arm.com>,
	Jesse Taube <Mr.Bossman075@gmail.com>,
	Giulio Benetti <giulio.benetti@benettiengineering.com>,
	Pierre Yves MORDRET <pierre-yves.mordret@st.com>,
	Alexandre TORGUE <alexandre.torgue@st.com>
Subject: RE: [PATCH] binfmt_flat: Remove shared library support
Date: Fri, 22 Apr 2022 15:18:20 +0000	[thread overview]
Message-ID: <DU0PR10MB61777257C9532D1E3155329A83F79@DU0PR10MB6177.EURPRD10.PROD.OUTLOOK.COM> (raw)
In-Reply-To: <CAK8P3a3Cjna7H_YxFvg6UEOqQf9ZqLp9EVOCFFewzWBHVT4nWg@mail.gmail.com>

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Hi Arnd

Thanks for forwarding this patch.

As far as i know, we don't need CONFIG_BINFMT_SHARED_FLAT flag.
Tested on stm32f769-disco board

You can add my :
Tested-by: Patrice Chotard <patrice.chotard@foss.st.com>

Thanks
Patrice
________________________________
De : Arnd Bergmann <arnd@arndb.de>
Envoyé : jeudi 21 avril 2022 09:12
À : Geert Uytterhoeven <geert@linux-m68k.org>
Cc : Greg Ungerer <gerg@linux-m68k.org>; Eric W. Biederman <ebiederm@xmission.com>; Kees Cook <keescook@chromium.org>; Niklas Cassel <Niklas.Cassel@wdc.com>; Damien Le Moal <damien.lemoal@opensource.wdc.com>; Alexander Viro <viro@zeniv.linux.org.uk>; Paul Walmsley <paul.walmsley@sifive.com>; Palmer Dabbelt <palmer@dabbelt.com>; Albert Ou <aou@eecs.berkeley.edu>; Mike Frysinger <vapier@gentoo.org>; stable@vger.kernel.org <stable@vger.kernel.org>; linux-fsdevel@vger.kernel.org <linux-fsdevel@vger.kernel.org>; linux-mm@kvack.org <linux-mm@kvack.org>; linux-riscv@lists.infradead.org <linux-riscv@lists.infradead.org>; Linux-Arch <linux-arch@vger.kernel.org>; linux-m68k <linux-m68k@lists.linux-m68k.org>; Linux ARM <linux-arm-kernel@lists.infradead.org>; Linux-sh list <linux-sh@vger.kernel.org>; Yoshinori Sato <ysato@users.sourceforge.jp>; Rich Felker <dalias@libc.org>; Sudeep Holla <sudeep.holla@arm.com>; Vladimir Murzin <vladimir.murzin@arm.com>; Jesse Taube <Mr.Bossman075@gmail.com>; Giulio Benetti <giulio.benetti@benettiengineering.com>; Patrice CHOTARD <patrice.chotard@st.com>; Pierre Yves MORDRET <pierre-yves.mordret@st.com>; Alexandre TORGUE <alexandre.torgue@st.com>
Objet : Re: [PATCH] binfmt_flat: Remove shared library support

On Thu, Apr 21, 2022 at 8:52 AM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> On Thu, Apr 21, 2022 at 1:53 AM Greg Ungerer <gerg@linux-m68k.org> wrote:
> > On 21/4/22 00:58, Eric W. Biederman wrote:
> > > In a recent discussion[1] it was reported that the binfmt_flat library
> > > support was only ever used on m68k and even on m68k has not been used
> > > in a very long time.
> > >
> > > The structure of binfmt_flat is different from all of the other binfmt
> > > implementations becasue of this shared library support and it made
> > > life and code review more effort when I refactored the code in fs/exec.c.
> > >
> > > Since in practice the code is dead remove the binfmt_flat shared libarary
> > > support and make maintenance of the code easier.
> > >
> > > [1] https://lkml.kernel.org/r/81788b56-5b15-7308-38c7-c7f2502c4e15@linux-m68k.org
> > > Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
> > > ---
> > >
> > > Can the binfmt_flat folks please verify that the shared library support
> > > really isn't used?
> >
> > I can definitely confirm I don't use it on m68k. And I don't know of
> > anyone that has used it in many years.
> >
> >
> > > Was binfmt_flat being enabled on arm and sh the mistake it looks like?
>
> I think the question was intended to be
>
>     Was *binfmt_flat_shared_flat* being enabled on arm and sh the
>     mistake it looks like?
>
> > >
> > >   arch/arm/configs/lpc18xx_defconfig |   1 -
> > >   arch/arm/configs/mps2_defconfig    |   1 -
> > >   arch/arm/configs/stm32_defconfig   |   1 -
> > >   arch/arm/configs/vf610m4_defconfig |   1 -

Adding stm32, mps2 and imxrt maintainers to Cc, they are the most active
armv7-m users and should know if the shared library support is used anywhere.

     Arnd

ST Restricted

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