kernel/linux.git/scripts/Kconfig.include, branch v6.19.11

init: deduplicate cc-can-link.sh invocations

2025-11-14T19:20:34+00:00

The command to invoke scripts/cc-can-link.sh is very long and new usages are about to be added. Add a helper variable to make the code easier to read and maintain. Signed-off-by: Thomas Weißschuh Reviewed-by: Nicolas Schier Reviewed-by: Nathan Chancellor Link: https://patch.msgid.link/20251114-kbuild-userprogs-bits-v3-2-4dee0d74d439@linutronix.de Signed-off-by: Nicolas Schier

kbuild: rust: add `CONFIG_RUSTC_LLVM_VERSION`

2024-10-13T20:22:28+00:00

Each version of Rust supports a range of LLVM versions. There are cases where we want to gate a config on the LLVM version instead of the Rust version. Normalized cfi integer tags are one example [1]. The invocation of rustc-version is being moved from init/Kconfig to scripts/Kconfig.include for consistency with cc-version. Link: https://lore.kernel.org/all/20240925-cfi-norm-kasan-fix-v1-1-0328985cdf33@google.com/ [1] Signed-off-by: Gary Guo Link: https://lore.kernel.org/r/20241011114040.3900487-1-gary@garyguo.net [ Added missing `-llvm` to the Usage documentation. - Miguel ] Signed-off-by: Miguel Ojeda

kbuild: rust: Define probing macros for rustc

2024-09-16T16:04:37+00:00

Creates flag probe macro variants for `rustc`. These are helpful because: 1. The kernel now supports a minimum `rustc` version rather than a single version. 2. `rustc` links against a range of LLVM revisions, occasionally even ones without an official release number. Since the availability of some Rust flags depends on which LLVM it has been linked against, probing is necessary. Signed-off-by: Matthew Maurer Link: https://github.com/Rust-for-Linux/linux/pull/1087 Link: https://lore.kernel.org/r/20240820194910.187826-2-mmaurer@google.com Signed-off-by: Miguel Ojeda

x86/kconfig: Add as-instr64 macro to properly evaluate AS_WRUSS

2024-06-20T17:48:18+00:00

Some instructions are only available on the 64-bit architecture. Bi-arch compilers that default to -m32 need the explicit -m64 option to evaluate them properly. Fixes: 18e66b695e78 ("x86/shstk: Add Kconfig option for shadow stack") Closes: https://lore.kernel.org/all/20240612-as-instr-opt-wrussq-v2-1-bd950f7eead7@gmail.com/ Reported-by: Dmitry Safonov <0x7f454c46@gmail.com> Signed-off-by: Masahiro Yamada Signed-off-by: Borislav Petkov (AMD) Tested-by: Dmitry Safonov <0x7f454c46@gmail.com> Link: https://lore.kernel.org/r/20240612050257.3670768-1-masahiroy@kernel.org

kbuild: Add -Wa,--fatal-warnings to as-instr invocation

2024-02-17T00:07:07+00:00

Certain assembler instruction tests may only induce warnings from the assembler on an unsupported instruction or option, which causes as-instr to succeed when it was expected to fail. Some tests workaround this limitation by additionally testing that invalid input fails as expected. However, this is fragile if the assembler is changed to accept the invalid input, as it will cause the instruction/option to be unavailable like it was unsupported even when it is. Use '-Wa,--fatal-warnings' in the as-instr macro to turn these warnings into hard errors, which avoids this fragility and makes tests more robust and well formed. Cc: stable@vger.kernel.org Suggested-by: Eric Biggers Signed-off-by: Nathan Chancellor Tested-by: Eric Biggers Tested-by: Andy Chiu Reviewed-by: Andy Chiu Tested-by: Conor Dooley Reviewed-by: Conor Dooley Acked-by: Masahiro Yamada Link: https://lore.kernel.org/r/20240125-fix-riscv-option-arch-llvm-18-v1-1-390ac9cc3cd0@kernel.org Signed-off-by: Palmer Dabbelt

kbuild: Update assembler calls to use proper flags and language target

2023-01-26T03:41:38+00:00

as-instr uses KBUILD_AFLAGS, but as-option uses KBUILD_CFLAGS. This can cause as-option to fail unexpectedly when CONFIG_WERROR is set, because clang will emit -Werror,-Wunused-command-line-argument for various -m and -f flags in KBUILD_CFLAGS for assembler sources. Callers of as-option and as-instr should be adding flags to KBUILD_AFLAGS / aflags-y, not KBUILD_CFLAGS / cflags-y. Use KBUILD_AFLAGS in all macros to clear up the initial problem. Unfortunately, -Wunused-command-line-argument can still be triggered with clang by the presence of warning flags or macro definitions because '-x assembler' is used, instead of '-x assembler-with-cpp', which will consume these flags. Switch to '-x assembler-with-cpp' in places where '-x assembler' is used, as the compiler is always used as the driver for out of line assembler sources in the kernel. Finally, add -Werror to these macros so that they behave consistently whether or not CONFIG_WERROR is set. [nathan: Reworded and expanded on problems in commit message Use '-x assembler-with-cpp' in a couple more places] Link: https://github.com/ClangBuiltLinux/linux/issues/1699 Suggested-by: Masahiro Yamada Signed-off-by: Nick Desaulniers Signed-off-by: Nathan Chancellor Tested-by: Linux Kernel Functional Testing Tested-by: Anders Roxell Signed-off-by: Masahiro Yamada

Kbuild: add Rust support

2022-09-28T07:02:20+00:00

Having most of the new files in place, we now enable Rust support in the build system, including `Kconfig` entries related to Rust, the Rust configuration printer and a few other bits. Reviewed-by: Kees Cook Reviewed-by: Nick Desaulniers Tested-by: Nick Desaulniers Reviewed-by: Greg Kroah-Hartman Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Finn Behrens Signed-off-by: Finn Behrens Co-developed-by: Adam Bratschi-Kaye Signed-off-by: Adam Bratschi-Kaye Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Co-developed-by: Michael Ellerman Signed-off-by: Michael Ellerman Co-developed-by: Sven Van Asbroeck Signed-off-by: Sven Van Asbroeck Co-developed-by: Gary Guo Signed-off-by: Gary Guo Co-developed-by: Boris-Chengbiao Zhou Signed-off-by: Boris-Chengbiao Zhou Co-developed-by: Boqun Feng Signed-off-by: Boqun Feng Co-developed-by: Douglas Su Signed-off-by: Douglas Su Co-developed-by: Dariusz Sosnowski Signed-off-by: Dariusz Sosnowski Co-developed-by: Antonio Terceiro Signed-off-by: Antonio Terceiro Co-developed-by: Daniel Xu Signed-off-by: Daniel Xu Co-developed-by: Björn Roy Baron Signed-off-by: Björn Roy Baron Co-developed-by: Martin Rodriguez Reboredo Signed-off-by: Martin Rodriguez Reboredo Signed-off-by: Miguel Ojeda

kbuild: set EXIT trap before creating temporary directory

2022-08-03T13:56:38+00:00

Swap the order of 'mkdir' and 'trap' just in case the subshell is interrupted between 'mkdir' and 'trap' although the effect might be subtle. This does not intend to make the cleanup perfect. There are more cases that miss to remove the tmp directory, for example: - When interrupted, dash does not invoke the EXIT trap (bash does) - 'rm' command might be interrupted before removing the directory I am not addressing all the cases since the tmp directory is harmless after all. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers

kconfig: shorten the temporary directory name for cc-option

2022-07-27T12:18:00+00:00

The cc-option macro creates the temporary directory, .tmp_$$$$. Shell expands '$$' into its process ID. '$$$$' results in repeated PID. In Makefile, '$$$$' is correct (see TMPOUT in scripts/Malefile.compiler) because '$$' is an escape sequence of '$'. Make expands '$$$$' into '$$', then shell expands it into the process ID. This does not apply to Kconfig because Kconfig requires variable references to be enclosed by curly braces, like ${variable}. The '$' that is not followed by '{' loses its effect. Signed-off-by: Masahiro Yamada Tested-by: Nicolas Schier

kbuild: check the minimum assembler version in Kconfig

2021-04-24T20:14:41+00:00

Documentation/process/changes.rst defines the minimum assembler version (binutils version), but we have never checked it in the build time. Kbuild never invokes 'as' directly because all assembly files in the kernel tree are *.S, hence must be preprocessed. I do not expect raw assembly source files (*.s) would be added to the kernel tree. Therefore, we always use $(CC) as the assembler driver, and commit aa824e0c962b ("kbuild: remove AS variable") removed 'AS'. However, we are still interested in the version of the assembler acting behind. As usual, the --version option prints the version string. $ as --version | head -n 1 GNU assembler (GNU Binutils for Ubuntu) 2.35.1 But, we do not have $(AS). So, we can add the -Wa prefix so that $(CC) passes --version down to the backing assembler. $ gcc -Wa,--version | head -n 1 gcc: fatal error: no input files compilation terminated. OK, we need to input something to satisfy gcc. $ gcc -Wa,--version -c -x assembler /dev/null -o /dev/null | head -n 1 GNU assembler (GNU Binutils for Ubuntu) 2.35.1 The combination of Clang and GNU assembler works in the same way: $ clang -no-integrated-as -Wa,--version -c -x assembler /dev/null -o /dev/null | head -n 1 GNU assembler (GNU Binutils for Ubuntu) 2.35.1 Clang with the integrated assembler fails like this: $ clang -integrated-as -Wa,--version -c -x assembler /dev/null -o /dev/null | head -n 1 clang: error: unsupported argument '--version' to option 'Wa,' For the last case, checking the error message is fragile. If the proposal for -Wa,--version support [1] is accepted, this may not be even an error in the future. One easy way is to check if -integrated-as is present in the passed arguments. We did not pass -integrated-as to CLANG_FLAGS before, but we can make it explicit. Nathan pointed out -integrated-as is the default for all of the architectures/targets that the kernel cares about, but it goes along with "explicit is better than implicit" policy. [2] With all this in my mind, I implemented scripts/as-version.sh to check the assembler version in Kconfig time. $ scripts/as-version.sh gcc GNU 23501 $ scripts/as-version.sh clang -no-integrated-as GNU 23501 $ scripts/as-version.sh clang -integrated-as LLVM 0 [1]: https://github.com/ClangBuiltLinux/linux/issues/1320 [2]: https://lore.kernel.org/linux-kbuild/20210307044253.v3h47ucq6ng25iay@archlinux-ax161/ Signed-off-by: Masahiro Yamada Reviewed-by: Nathan Chancellor