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;
MIME-Version: 1.0
References: <202306110855.7TlBCIzI-lkp@intel.com>
In-Reply-To: <202306110855.7TlBCIzI-lkp@intel.com>
From:   Alexandre Ghiti <alexghiti@rivosinc.com>
Date:   Tue, 13 Jun 2023 10:16:54 +0200
Message-ID: <CAHVXubhKstDeRDp8n-POR_eL0vh5DdHuWKHu7pN+X_j0rtG4Dw@mail.gmail.com>
Subject: Re: ld.lld: error: relocation R_RISCV_HI20 cannot be used against
 symbol 'misaligned_access_speed'; recompile with -fPIC
To:     kernel test robot <lkp@intel.com>
Cc:     llvm@lists.linux.dev, oe-kbuild-all@lists.linux.dev,
        linux-kernel@vger.kernel.org, Palmer Dabbelt <palmer@rivosinc.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

On Sun, Jun 11, 2023 at 2:11=E2=80=AFAM kernel test robot <lkp@intel.com> w=
rote:
>
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.gi=
t master
> head:   022ce8862dff83c859089cd14bc4dca0733e2f90
> commit: 8dc2a7e8027fbeca0c7df81d4c82e735a59b5741 riscv: Fix relocatable k=
ernels with early alternatives using -fno-pie
> date:   10 days ago
> config: riscv-randconfig-r022-20230611 (https://download.01.org/0day-ci/a=
rchive/20230611/202306110855.7TlBCIzI-lkp@intel.com/config)
> compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git =
ae42196bc493ffe877a7e3dff8be32035dea4d07)
> reproduce (this is a W=3D1 build):
>         mkdir -p ~/bin
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbi=
n/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # install riscv cross compiling tool for clang build
>         # apt-get install binutils-riscv64-linux-gnu
>         # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.=
git/commit/?id=3D8dc2a7e8027fbeca0c7df81d4c82e735a59b5741
>         git remote add linus https://git.kernel.org/pub/scm/linux/kernel/=
git/torvalds/linux.git
>         git fetch --no-tags linus master
>         git checkout 8dc2a7e8027fbeca0c7df81d4c82e735a59b5741
>         # save the config file
>         mkdir build_dir && cp config build_dir/.config
>         COMPILER_INSTALL_PATH=3D$HOME/0day COMPILER=3Dclang ~/bin/make.cr=
oss W=3D1 O=3Dbuild_dir ARCH=3Driscv olddefconfig
>         COMPILER_INSTALL_PATH=3D$HOME/0day COMPILER=3Dclang ~/bin/make.cr=
oss W=3D1 O=3Dbuild_dir ARCH=3Driscv SHELL=3D/bin/bash
>
> If you fix the issue in a separate patch/commit (i.e. not just a new vers=
ion of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202306110855.7TlBCIzI-lkp=
@intel.com/
>
> All errors (new ones prefixed by >>):
>
> >> ld.lld: error: relocation R_RISCV_HI20 cannot be used against symbol '=
misaligned_access_speed'; recompile with -fPIC
>    >>> defined in vmlinux.a(arch/riscv/kernel/cpufeature.o)
>    >>> referenced by errata.c:42 (arch/riscv/errata/thead/errata.c:42)
>    >>>               arch/riscv/errata/thead/errata.o:(thead_feature_prob=
e_func) in archive vmlinux.a
> --
> >> ld.lld: error: relocation R_RISCV_LO12_I cannot be used against symbol=
 'misaligned_access_speed'; recompile with -fPIC
>    >>> defined in vmlinux.a(arch/riscv/kernel/cpufeature.o)
>    >>> referenced by errata.c:42 (arch/riscv/errata/thead/errata.c:42)
>    >>>               arch/riscv/errata/thead/errata.o:(thead_feature_prob=
e_func) in archive vmlinux.a
> --
> >> ld.lld: error: relocation R_RISCV_HI20 cannot be used against symbol '=
riscv_cbom_block_size'; recompile with -fPIC
>    >>> defined in vmlinux.a(arch/riscv/mm/cacheflush.o)
>    >>> referenced by errata.c:42 (arch/riscv/errata/thead/errata.c:42)
>    >>>               arch/riscv/errata/thead/errata.o:(thead_errata_patch=
_func) in archive vmlinux.a
> --
> >> ld.lld: error: relocation R_RISCV_LO12_S cannot be used against symbol=
 'riscv_cbom_block_size'; recompile with -fPIC
>    >>> defined in vmlinux.a(arch/riscv/mm/cacheflush.o)
>    >>> referenced by errata.c:42 (arch/riscv/errata/thead/errata.c:42)
>    >>>               arch/riscv/errata/thead/errata.o:(thead_errata_patch=
_func) in archive vmlinux.a
> --
> >> ld.lld: error: relocation R_RISCV_HI20 cannot be used against symbol '=
__per_cpu_offset'; recompile with -fPIC
>    >>> defined in vmlinux.a(mm/percpu.o)
>    >>> referenced by errata.c:42 (arch/riscv/errata/thead/errata.c:42)
>    >>>               arch/riscv/errata/thead/errata.o:(thead_feature_prob=
e_func) in archive vmlinux.a
> --
> >> ld.lld: error: relocation R_RISCV_LO12_I cannot be used against symbol=
 '__per_cpu_offset'; recompile with -fPIC
>    >>> defined in vmlinux.a(mm/percpu.o)
>    >>> referenced by errata.c:42 (arch/riscv/errata/thead/errata.c:42)
>    >>>               arch/riscv/errata/thead/errata.o:(thead_feature_prob=
e_func) in archive vmlinux.a
>

So I looked into those errors, the config is basically =3D RELOCATABLE +
MEDLOW - EARLY_ALTERNATIVES. Then errata/thead is not compiled as
medany, which makes sense since we only need this code to be medany
when EARLY_ALTERNATIVES is enabled (because the code would be executed
with mmu off, which is not the case here).

I can fix those errors by adding the medany flag, but I'm not sure
actually we want to do that since we do not need it and gcc does not
complain: any idea?

Alex


> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki