Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Thu, 16 Jun 2022 09:09:51 +1000
From:   Stephen Rothwell <sfr@canb.auug.org.au>
To:     "Paul E. McKenney" <paulmck@kernel.org>
Cc:     Nathan Chancellor <nathan@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Frederic Weisbecker <frederic@kernel.org>,
        Sami Tolvanen <samitolvanen@google.com>, llvm@lists.linux.dev,
        linux-kernel@vger.kernel.org, linux-next@vger.kernel.org
Subject: Re: Contextual conflict between kspp and rcu trees
Message-ID: <20220616090951.6db6a36f@canb.auug.org.au>
In-Reply-To: <20220615211220.GJ1790663@paulmck-ThinkPad-P17-Gen-1>
References: <Yqo5SequJuC2qX6S@dev-arch.thelio-3990X>
        <202206151326.E34CDE453@keescook>
        <YqpCkAVTwpNn+6p9@dev-arch.thelio-3990X>
        <20220615211220.GJ1790663@paulmck-ThinkPad-P17-Gen-1>
MIME-Version: 1.0
Content-Type: multipart/signed; boundary="Sig_/ym87/RxWZO0REqS4MS/BmLz";
 protocol="application/pgp-signature"; micalg=pgp-sha256
Precedence: bulk

--Sig_/ym87/RxWZO0REqS4MS/BmLz
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: quoted-printable

Hi all,

On Wed, 15 Jun 2022 14:12:20 -0700 "Paul E. McKenney" <paulmck@kernel.org> =
wrote:
>
> On Wed, Jun 15, 2022 at 01:35:28PM -0700, Nathan Chancellor wrote:
> > On Wed, Jun 15, 2022 at 01:28:00PM -0700, Kees Cook wrote: =20
> > > On Wed, Jun 15, 2022 at 12:55:53PM -0700, Nathan Chancellor wrote: =20
> > > > Per the above RCU commit and commit 6c5218715286 ("context_tracking:
> > > > Take IRQ eqs entrypoints over RCU"), it appears that the following =
diff
> > > > is the proper fix up. Would you mind applying it to the merge of
> > > > whichever tree comes second if possible? I did build and boot test =
it
> > > > but it would not be a bad idea for Sami and Frederic to verify that=
 it
> > > > is correct so that Kees/Paul can mention it to Linus :) =20
> > >=20
> > > Actually, the CFI fix (and a few others) are meant to be sent for
> > > -rc3, so if the ct_irq_enter() change is in -next, this can maybe get
> > > sorted out? =20
> >=20
> > Ah, I had assumed that branch was destined for the next release. If it
> > is for 5.19 and they make -rc3 then it should be trivial for Paul to
> > either rebase the changes on -rc3 and apply that diff as part of
> > "context_tracking: Take IRQ eqs entrypoints over RCU" (if his tree is
> > mutable) or just merge -rc3 and apply that diff as part of the merge. I
> > don't really care how it gets resolved, just so long as it does :) =20
>=20
> My tree will remain mutable for a few more weeks, so we should be
> good.  ;-)

The CFI fix is in Linus' tree today.

Paul, you could just merge commit 1dfbe9fcda4a ("usercopy: Make
usercopy resilient against ridiculously large copies") from Linus' tree
(or rebase on top of that or 30306f6194ca "Merge tag
"hardening-v5.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kees=
/linux"
since it is based on -rc2).
--=20
Cheers,
Stephen Rothwell

--Sig_/ym87/RxWZO0REqS4MS/BmLz
Content-Type: application/pgp-signature
Content-Description: OpenPGP digital signature

-----BEGIN PGP SIGNATURE-----

iQEzBAEBCAAdFiEENIC96giZ81tWdLgKAVBC80lX0GwFAmKqZr8ACgkQAVBC80lX
0Gw7egf/bLTeP0zJ0wTcxbtxYY58bGgOo1TmzQoMVhzMfRVlBCc3r2/ErQn4x15Z
cV2DRq4fS8RHLdF09GDJV8pWT7Dq+rwiuVLudlc0nAaJTNc6b1ZJM1elGk9j8moJ
hlXuGJ0w+7cW2aQlHDSGONTWBiIU0Ev47vSWb7s6VgfOldHilCFvbL4pi1gzItkD
fn8BQCBEmq7fzI7VNeaMNJXjfuW/GyBqh3NzTpIEOotTQUWMFeCZ8IBKnKugh2G/
WObBzbcdv9ffAvZVZ/9hJ+hIp60cj7n2nttkbfCL1zXMrrNK999IozTxGu53rNmX
MdtB/OuDDZAh6Vdn8fSLZYwRjlGxKw==
=w+wS
-----END PGP SIGNATURE-----

--Sig_/ym87/RxWZO0REqS4MS/BmLz--