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;
Date:   Fri, 22 May 2020 03:31:19 +1000
From:   Stephen Rothwell <sfr@canb.auug.org.au>
To:     Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Peter Zijlstra <peterz@infradead.org>
Cc:     Linux Next Mailing List <linux-next@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Will Deacon <will@kernel.org>
Subject: linux-next: build failure after merge of the tip tree
Message-ID: <20200522033119.1bbd99c5@canb.auug.org.au>
MIME-Version: 1.0
Content-Type: multipart/signed; boundary="Sig_/wrxL7s9suCEcfFWKJZTtC/p";
 protocol="application/pgp-signature"; micalg=pgp-sha256
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

--Sig_/wrxL7s9suCEcfFWKJZTtC/p
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: quoted-printable

Hi all,

After merging the tip tree, all my linux-next builds took signficantly
longer and used much more memory.  In some cases, builds would seg fault
due to running out of memory :-(

I have eventaully bisected it to commit

  cdd28ad2d811 ("READ_ONCE: Use data_race() to avoid KCSAN instrumentation")

For my (e.g.) x86_64 allmodconfig builds (cross compiled on PowerPC le,
-j80) the elapsed time went from around 9 minutes to over 17 minutes
and the maximum resident size (as reported by /usr/bin/time) from around
500M to around 2G (I saw lots of cc1 processes over 2G in size).

For tomorrow's linux-next (well, later today :-() I will revert that
commit (and its child) when I merge the tip tree.

--=20
Cheers,
Stephen Rothwell

--Sig_/wrxL7s9suCEcfFWKJZTtC/p
Content-Type: application/pgp-signature
Content-Description: OpenPGP digital signature

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

iQEzBAEBCAAdFiEENIC96giZ81tWdLgKAVBC80lX0GwFAl7GuucACgkQAVBC80lX
0GzOewf/azkhBK6A/fGfOMCMgugNIwuaoC8kaoodaK1hGp1iaXgXcHZvJ4EUOiwj
lMP8BiS2IxypBpPteksM+hUjO0thTNCQ07PlnmfLXEv4JPezAZF8jCvk/ZxHaUzz
ZuKA49fsQ5SDRsD10rayvwqyf7OGLTNpsvRA/kd9SxM3tjV1ayLo+4fe1YcrnjcE
FYHormIYKPWT6/qkpjp60pYmV0DFWzw013dXEM75npvaiErKKrP7H+li8fjWrxJo
H1Fjhuh3UtWcCkCOGxU/oCbS/EmPyZEghu1l6g9LpJzKfSSPcVs6jywL9PQ+ugZG
JBqE4uKAgvyzvhAAWIp7UGwe6A7ZxQ==
=7ehF
-----END PGP SIGNATURE-----

--Sig_/wrxL7s9suCEcfFWKJZTtC/p--