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:   Wed, 2 Aug 2023 08:48:36 +0100
From:   Conor Dooley <conor.dooley@microchip.com>
To:     Minda Chen <minda.chen@starfivetech.com>
CC:     Conor Dooley <conor@kernel.org>,
        Jisheng Zhang <jszhang@kernel.org>,
        Samuel Holland <samuel@sholland.org>,
        Dao Lu <daolu@rivosinc.com>, Heiko Stuebner <heiko@sntech.de>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        <linux-kernel@vger.kernel.org>, <linux-riscv@lists.infradead.org>,
        Mason Huo <mason.huo@starfivetech.com>,
        <stable@vger.kernel.org>
Subject: Re: [PATCH v1] riscv: Using TOOLCHAIN_HAS_ZIHINTPAUSE marco replace
 zihintpause
Message-ID: <20230802-seismic-gallstone-fca0f4b17076@wendy>
References: <20230802064215.31111-1-minda.chen@starfivetech.com>
 <20230802-sharpness-spoon-f9b8804fb66f@wendy>
 <d64874cb-8628-a6d2-d2f4-8af4d0ebf8b2@starfivetech.com>
MIME-Version: 1.0
Content-Type: multipart/signed; micalg=pgp-sha256;
        protocol="application/pgp-signature"; boundary="JTYctk/RlWnk7XbV"
Content-Disposition: inline
In-Reply-To: <d64874cb-8628-a6d2-d2f4-8af4d0ebf8b2@starfivetech.com>
Precedence: bulk

--JTYctk/RlWnk7XbV
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On Wed, Aug 02, 2023 at 03:32:15PM +0800, Minda Chen wrote:
>=20
>=20
> On 2023/8/2 14:54, Conor Dooley wrote:
> > Hey Minda,
> >=20
> > On Wed, Aug 02, 2023 at 02:42:15PM +0800, Minda Chen wrote:
> >> Actually it is a part of Conor's
> >> commit aae538cd03bc ("riscv: fix detection of toolchain
> >> Zihintpause support").
> >> It is looks like a merge issue.
> >=20
> > Yup, spot on.
> >=20
> >> Samuel's
> >> commit 0b1d60d6dd9e ("riscv: Fix build with
> >> CONFIG_CC_OPTIMIZE_FOR_SIZE=3Dy") do not base on Conor's commit and
> >> revert to __riscv_zihintpause. So this patch can fix it.
> >>=20
> >> Signed-off-by: Minda Chen <minda.chen@starfivetech.com>
> >=20
> > Did you actually manage to trigger this, or was this by inspection?
> > clang-15 + binutils 2.35 was, IIRC, how we spotted this because that's
> > what the clang-built-linux CI uses to test the LTS kernels from before
> > LLVM's IAS was supported for RISC-V. Seemingly all that needs to be
> > satisfied there is that zihintpause doesn't appear in -march so this has
> > gone unnoticed.
> >=20
> > Fixes: 3c349eacc559 ("Merge patch "riscv: Fix build with CONFIG_CC_OPTI=
MIZE_FOR_SIZE=3Dy"")
> > Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
> >=20
> > Thanks,
> > Conor.
> >=20
> Thanks, Conor. I found this just by inspection. I found a issue that vdso=
=2Eso call cpu_relax
> cause application core dump in kernel 6.1.31. I need Samuel'patch to fix =
this. And I search the log
> of processor.h found this issue.

That doesn't look like it is fixed in later stable kernels (we are at
6.1.42-rcN right now I think). It sounds we should ask Greg to backport
0b1d60d6dd9e ("riscv: Fix build with CONFIG_CC_OPTIMIZE_FOR_SIZE=3Dy")
to 6.1. Does that make sense to you?

--JTYctk/RlWnk7XbV
Content-Type: application/pgp-signature; name="signature.asc"

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

iHUEABYIAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCZMoKVAAKCRB4tDGHoIJi
0qGuAP4k6WdiXs2y09Sk66yBTqGCWcA0PLL/uBMrEneon9j7pgEA8KYUThTRSCMA
ZVvVDzsueLWC7z+D9r5SulFqPvZ5ZAo=
=Qq1m
-----END PGP SIGNATURE-----

--JTYctk/RlWnk7XbV--