6.7-stable review patch. If anyone has any objections, please let me know.
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From: Nathan Chancellor nathan@kernel.org
commit 3aff0c459e77ac0fb1c4d6884433467f797f7357 upstream.
Commit e4bb020f3dbb ("riscv: detect assembler support for .option arch") added two tests, one for a valid value to '.option arch' that should succeed and one for an invalid value that is expected to fail to make sure that support for '.option arch' is properly detected because Clang does not error when '.option arch' is not supported:
$ clang --target=riscv64-linux-gnu -Werror -x assembler -c -o /dev/null <(echo '.option arch, +m') /dev/fd/63:1:9: warning: unknown option, expected 'push', 'pop', 'rvc', 'norvc', 'relax' or 'norelax' .option arch, +m ^ $ echo $? 0
Unfortunately, the invalid test started being accepted by Clang after the linked llvm-project change, which causes CONFIG_AS_HAS_OPTION_ARCH and configurations that depend on it to be silently disabled, even though those versions do support '.option arch'.
The invalid test can be avoided altogether by using '-Wa,--fatal-warnings', which will turn all assembler warnings into errors, like '-Werror' does for the compiler:
$ clang --target=riscv64-linux-gnu -Werror -Wa,--fatal-warnings -x assembler -c -o /dev/null <(echo '.option arch, +m') /dev/fd/63:1:9: error: unknown option, expected 'push', 'pop', 'rvc', 'norvc', 'relax' or 'norelax' .option arch, +m ^ $ echo $? 1
The as-instr macros have been updated to make use of this flag, so remove the invalid test, which allows CONFIG_AS_HAS_OPTION_ARCH to work for all compiler versions.
Cc: stable@vger.kernel.org Fixes: e4bb020f3dbb ("riscv: detect assembler support for .option arch") Link: https://github.com/llvm/llvm-project/commit/3ac9fe69f70a2b3541266daedbaaa7dc... Reported-by: Eric Biggers ebiggers@kernel.org Closes: https://lore.kernel.org/r/20240121011341.GA97368@sol.localdomain/ Signed-off-by: Nathan Chancellor nathan@kernel.org Tested-by: Eric Biggers ebiggers@google.com Tested-by: Andy Chiu andybnac@gmail.com Reviewed-by: Andy Chiu andybnac@gmail.com Tested-by: Conor Dooley conor.dooley@microchip.com Reviewed-by: Conor Dooley conor.dooley@microchip.com Acked-by: Masahiro Yamada masahiroy@kernel.org Link: https://lore.kernel.org/r/20240125-fix-riscv-option-arch-llvm-18-v1-2-390ac9... Signed-off-by: Palmer Dabbelt palmer@rivosinc.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/riscv/Kconfig | 1 - 1 file changed, 1 deletion(-)
--- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -294,7 +294,6 @@ config AS_HAS_OPTION_ARCH # https://reviews.llvm.org/D123515 def_bool y depends on $(as-instr, .option arch$(comma) +m) - depends on !$(as-instr, .option arch$(comma) -i)
source "arch/riscv/Kconfig.socs" source "arch/riscv/Kconfig.errata"