From: Nick Desaulniers <ndesaulniers@google.com>
To: Borislav Petkov <bp@alien8.de>
Cc: Ilie Halip <ilie.halip@gmail.com>,
LKML <linux-kernel@vger.kernel.org>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
"maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)"
<x86@kernel.org>,
clang-built-linux <clang-built-linux@googlegroups.com>
Subject: Re: [PATCH V2] x86/boot: explicitly place .eh_frame after .rodata
Date: Mon, 18 Nov 2019 09:46:23 -0800 [thread overview]
Message-ID: <CAKwvOdmWoHqrUyZ-_ino9z7KRzizpdoY2ZL5ngUzwGy55MuZ4g@mail.gmail.com> (raw)
In-Reply-To: <20191118143553.GD6363@zn.tnic>
On Mon, Nov 18, 2019 at 6:36 AM Borislav Petkov <bp@alien8.de> wrote:
>
> On Wed, Nov 06, 2019 at 02:06:28PM +0200, Ilie Halip wrote:
> > diff --git a/arch/x86/boot/setup.ld b/arch/x86/boot/setup.ld
> > index 0149e41d42c2..30ce52635cd0 100644
> > --- a/arch/x86/boot/setup.ld
> > +++ b/arch/x86/boot/setup.ld
> > @@ -25,6 +25,7 @@ SECTIONS
> >
> > . = ALIGN(16);
> > .rodata : { *(.rodata*) }
> > + .eh_frame : { *(.eh_frame) }
>
> The kernel proper linker script does
>
> /DISCARD/ : {
> *(.eh_frame)
> }
>
> with the .eh_frame section.
>
> Wouldn't that solve your issue too, if you add it to the /DISCARD/
> section in that linker script too?
Yep. Looks like:
- arch/x86/kernel/vmlinux.lds.S
- arch/x86/realmode/rm/realmode.lds.S
discard .eh_frame, while
- arch/x86/entry/vdso/vdso-layout.lds.S
- arch/x86/um/vdso/vdso-layout.lds.S
keep it. I assume then that just vdso code that get linked into
userspace needs to preserve this. This suggestion would be a
functional change, which is why we pursued the conservative change
preserving it.
https://github.com/ClangBuiltLinux/linux/issues/760#issuecomment-549192213
Ilie, would you mind sending a v3 with Boris' recommendation?
--
Thanks,
~Nick Desaulniers
next prev parent reply other threads:[~2019-11-18 17:46 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-04 9:03 [PATCH] x86/boot: explicitly place .eh_frame after .rodata Ilie Halip
2019-11-04 17:54 ` Nick Desaulniers
2019-11-05 14:37 ` Ilie Halip
2019-11-06 12:06 ` [PATCH V2] " Ilie Halip
2019-11-06 17:23 ` Nick Desaulniers
2019-11-18 10:22 ` Ilie Halip
2019-11-18 14:35 ` Borislav Petkov
2019-11-18 17:46 ` Nick Desaulniers [this message]
2019-11-18 17:52 ` Borislav Petkov
2019-11-26 14:45 ` [PATCH v3] x86/boot: discard .eh_frame sections Ilie Halip
2019-11-26 17:16 ` Nick Desaulniers
2019-12-06 21:53 ` Nick Desaulniers
2019-12-14 7:12 ` [tip: x86/boot] x86/boot: Discard " tip-bot2 for Ilie Halip
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAKwvOdmWoHqrUyZ-_ino9z7KRzizpdoY2ZL5ngUzwGy55MuZ4g@mail.gmail.com \
--to=ndesaulniers@google.com \
--cc=bp@alien8.de \
--cc=clang-built-linux@googlegroups.com \
--cc=hpa@zytor.com \
--cc=ilie.halip@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).