This is a note to let you know that I've just added the patch titled
RISC-V: Drop invalid test from CONFIG_AS_HAS_OPTION_ARCH
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
risc-v-drop-invalid-test-from-config_as_has_option_arch.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 3aff0c459e77ac0fb1c4d6884433467f797f7357 Mon Sep 17 00:00:00 2001
From: Nathan Chancellor <nathan@xxxxxxxxxx>
Date: Thu, 25 Jan 2024 10:32:12 -0700
Subject: RISC-V: Drop invalid test from CONFIG_AS_HAS_OPTION_ARCH
From: Nathan Chancellor <nathan@xxxxxxxxxx>
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@xxxxxxxxxxxxxxx
Fixes: e4bb020f3dbb ("riscv: detect assembler support for .option arch")
Link: https://github.com/llvm/llvm-project/commit/3ac9fe69f70a2b3541266daedbaaa7dc9c007a2a
Reported-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Closes: https://lore.kernel.org/r/20240121011341.GA97368@sol.localdomain/
Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>
Tested-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Tested-by: Andy Chiu <andybnac@xxxxxxxxx>
Reviewed-by: Andy Chiu <andybnac@xxxxxxxxx>
Tested-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
Reviewed-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
Acked-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240125-fix-riscv-option-arch-llvm-18-v1-2-390ac9cc3cd0@xxxxxxxxxx
Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/riscv/Kconfig | 1 -
1 file changed, 1 deletion(-)
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -287,7 +287,6 @@ 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"
Patches currently in stable-queue which might be from nathan@xxxxxxxxxx are
queue-6.6/kbuild-add-wa-fatal-warnings-to-as-instr-invocation.patch
queue-6.6/risc-v-drop-invalid-test-from-config_as_has_option_arch.patch
