Re: [PATCH] Documentation/changes: Raise minimum supported binutils version to 2.23

[Masahiro Yamada]

On Tue, Mar 24, 2020 at 6:02 PM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
>
> Hi.
>
>
>
> On Tue, Mar 24, 2020 at 5:51 AM Kees Cook <keescook@xxxxxxxxxxxx> wrote:
> >
> > On Mon, Mar 23, 2020 at 02:44:54PM -0600, Jason A. Donenfeld wrote:
> > > On Mon, Mar 16, 2020 at 05:02:59PM +0100, Borislav Petkov wrote:
> > > > Long overdue patch, see below.
> > > >
> > > > Plan is to queue it after 5.7-rc1.
> > > >
> > > > ---
> > > > From: Borislav Petkov <bp@xxxxxxx>
> > > > Date: Mon, 16 Mar 2020 16:28:36 +0100
> > > > Subject: [PATCH] Documentation/changes: Raise minimum supported binutilsa version to 2.23
> > > >
> > > > The currently minimum-supported binutils version 2.21 has the problem of
> > > > promoting symbols which are defined outside of a section into absolute.
> > > > According to Arvind:
> > > >
> > > >   binutils-2.21 and -2.22. An x86-64 defconfig will fail with
> > > >           Invalid absolute R_X86_64_32S relocation: _etext
> > > >   and after fixing that one, with
> > > >           Invalid absolute R_X86_64_32S relocation: __end_of_kernel_reserve
> > > >
> > > > Those two versions of binutils have a bug when it comes to handling
> > > > symbols defined outside of a section and binutils 2.23 has the proper
> > > > fix, see: https://sourceware.org/legacy-ml/binutils/2012-06/msg00155.html


This seems to be also related to
7883a14339299773b2ce08dcfd97c63c199a9289


I had noticed the symbol "_text"
was absolute on binutils <= 2.22,
but I was not sure whether it was a bug of the tool.

I applied the fix.
Perhaps, it was unneeded given that
we require the binutils 2.23





> > > >
> > > > Therefore, up to the fixed version directly, skipping the broken ones.
> > > >
> > > > Currently shipping distros already have the fixed binutils version so
> > > > there should be no breakage resulting from this.
> > > >
> > > > For more details about the whole thing, see the thread in Link.
> > >
> > > That sounds very good to me. Then we'll be able to use ADX instructions
> > > without ifdefs.
> > >
> > > Acked-by: Jason A. Donenfeld <Jason@xxxxxxxxx>
> >
> > Can you send these now and we can land in 5.7 with the doc change?
> >
> > -Kees
>
>
> Kees,
>
> I folded this patch into the following series (16 patches):
> https://lore.kernel.org/patchwork/project/lkml/list/?series=435391
>
> This patch (14/16) is a prerequisite for 15/16.
>
>
>
> Borislav,
>
> When I forwarded this patch, I fixed up one more line.
> (changes.rst duplicates the same information...)
>
> Please see this. I hope this should be OK.
> https://lore.kernel.org/patchwork/patch/1214519/
>
>
>
> > --
> > Kees Cook
>
>
>
> --
> Best Regards
> Masahiro Yamada



-- 
Best Regards
Masahiro Yamada