Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) client-ip=2620:137:e000::3:7;
Date:   Mon, 11 Dec 2023 22:51:04 +0000
From:   Conor Dooley <conor@kernel.org>
To:     Alexandre Ghiti <alexghiti@rivosinc.com>
Cc:     Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
        syzbot+afb726d49f84c8d95ee1@syzkaller.appspotmail.com
Subject: Re: [PATCH -fixes] riscv: Fix wrong usage of lm_alias() when
 splitting a huge linear mapping
Message-ID: <20231211-deviancy-uncooked-6a24328f6200@spud>
References: <20231211141929.74027-1-alexghiti@rivosinc.com>
MIME-Version: 1.0
Content-Type: multipart/signed; micalg=pgp-sha256;
        protocol="application/pgp-signature"; boundary="3GQRIqzq/daVXmBi"
Content-Disposition: inline
In-Reply-To: <20231211141929.74027-1-alexghiti@rivosinc.com>
Precedence: bulk


--3GQRIqzq/daVXmBi
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On Mon, Dec 11, 2023 at 03:19:29PM +0100, Alexandre Ghiti wrote:
> lm_alias() can only be used on kernel mappings since it explicitly uses
> __pa_symbol(), so simply fix this by checking where the address belongs
> to before.
>=20
> Fixes: 311cd2f6e253 ("riscv: Fix set_memory_XX() and set_direct_map_XX() =
by splitting huge linear mappings")
> Reported-by: syzbot+afb726d49f84c8d95ee1@syzkaller.appspotmail.com
> Closes: https://lore.kernel.org/linux-riscv/000000000000620dd0060c02c5e1@=
google.com/
> Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>

=2E./arch/riscv/mm/pageattr.c:311:14: warning: variable 'ret' is used unini=
tialized whenever '&&' condition is false [-Wsometimes-uninitialized]

> ---
>  arch/riscv/mm/pageattr.c | 13 ++++++++++---
>  1 file changed, 10 insertions(+), 3 deletions(-)
>=20
> diff --git a/arch/riscv/mm/pageattr.c b/arch/riscv/mm/pageattr.c
> index fc5fc4f785c4..f5f8aa1d38d6 100644
> --- a/arch/riscv/mm/pageattr.c
> +++ b/arch/riscv/mm/pageattr.c
> @@ -304,9 +304,16 @@ static int __set_memory(unsigned long addr, int nump=
ages, pgprot_t set_mask,
>  			if (ret)
>  				goto unlock;
>  		}
> -	} else if (is_kernel_mapping(start) || is_linear_mapping(start)) {
> -		lm_start =3D (unsigned long)lm_alias(start);
> -		lm_end =3D (unsigned long)lm_alias(end);
> +	} else {
> +		if (is_kernel_mapping(start)) {
> +			lm_start =3D (unsigned long)lm_alias(start);
> +			lm_end =3D (unsigned long)lm_alias(end);
> +		} else if (is_linear_mapping(start)) {
> +			lm_start =3D start;
> +			lm_end =3D end;
> +		} else {
> +			goto unlock;
> +		}
> =20
>  		ret =3D split_linear_mapping(lm_start, lm_end);
>  		if (ret)
> --=20
> 2.39.2
>=20
>=20
> _______________________________________________
> linux-riscv mailing list
> linux-riscv@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-riscv

--3GQRIqzq/daVXmBi
Content-Type: application/pgp-signature; name="signature.asc"

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

iHUEABYIAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCZXeSWAAKCRB4tDGHoIJi
0sVlAP0T5/oaW6j/LkQ397MBYUvh8Eco7FXATW3thQaTZIN6qgD/XGQBW9AY5sDC
2YwV/oLkT6RTgaar8D58YdjsAjmF+g0=
=g9/e
-----END PGP SIGNATURE-----

--3GQRIqzq/daVXmBi--