Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: quoted-printable
In-Reply-To: <YCU9zoiw8EZktw5U@kroah.com>
References: <20201207170533.10738-1-mark.rutland@arm.com> <202012081319.D5827CF@keescook> <X9DkdTGAiAEfUvm5@kroah.com> <161300376813.1254594.5196098885798133458@swboyd.mtv.corp.google.com> <YCU9zoiw8EZktw5U@kroah.com>
Subject: Re: [PATCH] lkdtm: don't move ctors to .rodata
From:   Stephen Boyd <swboyd@chromium.org>
Cc:     Kees Cook <keescook@chromium.org>,
        Mark Rutland <mark.rutland@arm.com>,
        linux-kernel@vger.kernel.org, Arnd Bergmann <arnd@arndb.de>,
        stable@vger.kernel.org
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date:   Thu, 11 Feb 2021 10:53:10 -0800
Message-ID: <161306959090.1254594.16358795480052823449@swboyd.mtv.corp.google.com>
User-Agent: alot/0.9.1
Precedence: bulk

Quoting Greg Kroah-Hartman (2021-02-11 06:23:10)
> On Wed, Feb 10, 2021 at 04:36:08PM -0800, Stephen Boyd wrote:
> > Quoting Greg Kroah-Hartman (2020-12-09 06:51:33)
> > > On Tue, Dec 08, 2020 at 01:20:56PM -0800, Kees Cook wrote:
> > > > On Mon, Dec 07, 2020 at 05:05:33PM +0000, Mark Rutland wrote:
> > > > > [    0.969110] Code: 00000003 00000000 00000000 00000000 (0000000=
0)
> > > > > [    0.970815] ---[ end trace b5339784e20d015c ]---
> > > > >=20
> > > > > Signed-off-by: Mark Rutland <mark.rutland@arm.com>
> > > >=20
> > > > Oh, eek. Why was a ctor generated at all? But yes, this looks good.
> > > > Greg, can you pick this up please?
> > > >=20
> > > > Acked-by: Kees Cook <keescook@chromium.org>
> > >=20
> > > Now picked up, thanks.
> > >=20
> >=20
> > Can this be backported to 5.4 and 5.10 stable trees? I just ran across
> > this trying to use kasan on 5.4 with lkdtm and it blows up early. This
> > patch applies on 5.4 cleanly but doesn't compile because it's missing
> > noinstr. Here's a version of the patch that introduces noinstr on 5.4.97
> > so this patch can be picked to 5.4 stable trees.
>=20
> Why 5.10?  This showed up in 5.8, so how would it be needed there?
>=20

Sorry for the confusion. Can commit 655389666643 ("vmlinux.lds.h: Create
section for protection against instrumentation") and commit 3f618ab33234
("lkdtm: don't move ctors to .rodata") be backported to 5.4.y and only
commit 3f618ab3323407ee4c6a6734a37eb6e9663ebfb9 be backported to 5.10.y?