linux-kernel - Re: [PATCH v2] kbuild: Fail if gold linker is detected

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Sat, 20 Jul 2019 10:12:10 +0100
From:   Mike Lothian <mike@...eburn.co.uk>
To:     Thomas Gleixner <tglx@...utronix.de>
Cc:     Masahiro Yamada <yamada.masahiro@...ionext.com>,
        Nathan Chancellor <natechancellor@...il.com>,
        LKML <linux-kernel@...r.kernel.org>,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        X86 ML <x86@...nel.org>, "H.J. Lu" <hjl.tools@...il.com>,
        Linux Kbuild mailing list <linux-kbuild@...r.kernel.org>,
        "Theodore Y. Ts'o" <tytso@....edu>, linux-arch@...r.kernel.org
Subject: Re: [PATCH v2] kbuild: Fail if gold linker is detected

On Wed, 17 Jul 2019 at 08:57, Thomas Gleixner <tglx@...utronix.de> wrote:
>
> On Wed, 17 Jul 2019, Masahiro Yamada wrote:
> > On Wed, Jul 17, 2019 at 4:47 AM Thomas Gleixner <tglx@...utronix.de> wrote:
> > > So instead of dealing with attempts to duct tape gold support without
> > > understanding the root cause and without support from the gold folks, fail
> > > the build when gold is detected.
> > >
> >
> > The code looks OK in the build system point of view.
> >
> > Please let me confirm this, just in case:
> > For now, we give up all architectures, not only x86, right?
>
> Well, that's the logical consequence of a statement which says: don't use
> gold for the kernel.
>
> > I have not not heard much from other arch maintainers.
>
> Cc'ed linux-arch for that matter.
>
> Thanks,
>
>         tglx

Hi

I've done a bit more digging, I had a second machine that was building
Linus's tree just fine with ld.gold

I tried forcing ld.bfd on the problem machine and got this:

ld.bfd: arch/x86/boot/compressed/head_64.o: warning: relocation in
read-only section `.head.text'
ld.bfd: warning: creating a DT_TEXTREL in object

I had a look at the differences in the kernel configs and noticed this:

CONFIG_RANDOMIZE_BASE=y
CONFIG_X86_NEED_RELOCS=y
CONFIG_PHYSICAL_ALIGN=0x1000000
CONFIG_DYNAMIC_MEMORY_LAYOUT=y
CONFIG_RANDOMIZE_MEMORY=y
CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING=0x0

Unsetting CONFIG_RANDOMIZE_BASE=y gets things working for me with ld.gold again

In light of this - can we drop this patch?

Cheers

Mike