linux/rust
Masahiro Yamada 13b25489b6 kbuild: change working directory to external module directory with M=
Currently, Kbuild always operates in the output directory of the kernel,
even when building external modules. This increases the risk of external
module Makefiles attempting to write to the kernel directory.

This commit switches the working directory to the external module
directory, allowing the removal of the $(KBUILD_EXTMOD)/ prefix from
some build artifacts.

The command for building external modules maintains backward
compatibility, but Makefiles that rely on working in the kernel
directory may break. In such cases, $(objtree) and $(srctree) should
be used to refer to the output and source directories of the kernel.

The appearance of the build log will change as follows:

[Before]

  $ make -C /path/to/my/linux M=/path/to/my/externel/module
  make: Entering directory '/path/to/my/linux'
    CC [M]  /path/to/my/externel/module/helloworld.o
    MODPOST /path/to/my/externel/module/Module.symvers
    CC [M]  /path/to/my/externel/module/helloworld.mod.o
    CC [M]  /path/to/my/externel/module/.module-common.o
    LD [M]  /path/to/my/externel/module/helloworld.ko
  make: Leaving directory '/path/to/my/linux'

[After]

  $ make -C /path/to/my/linux M=/path/to/my/externel/module
  make: Entering directory '/path/to/my/linux'
  make[1]: Entering directory '/path/to/my/externel/module'
    CC [M]  helloworld.o
    MODPOST Module.symvers
    CC [M]  helloworld.mod.o
    CC [M]  .module-common.o
    LD [M]  helloworld.ko
  make[1]: Leaving directory '/path/to/my/externel/module'
  make: Leaving directory '/path/to/my/linux'

Printing "Entering directory" twice is cumbersome. This will be
addressed later.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
2024-11-28 08:10:23 +09:00
..
bindings rust: sort blk includes in bindings_helper.h 2024-08-21 00:37:02 +02:00
helpers rust: mutex: fix __mutex_init() usage in case of PREEMPT_RT 2024-09-26 21:22:15 +02:00
kernel Driver core fix for 6.12-rc3 2024-10-13 09:10:52 -07:00
macros Rust changes for v6.12 2024-09-25 10:25:40 -07:00
uapi rust: net::phy unified read/write API for C22 and C45 registers 2024-08-30 10:27:35 +01:00
.gitignore rust: support running Rust documentation tests as KUnit ones 2023-07-19 09:32:53 -06:00
bindgen_parameters rust: fix ARCH_SLAB_MINALIGN multiple definition error 2024-09-26 17:52:35 +02:00
build_error.rs rust: add build_error crate 2022-12-04 01:59:16 +01:00
compiler_builtins.rs rust: add intrinsics to fix -Os builds 2024-08-10 00:05:10 +02:00
exports.c rust: kbuild: auto generate helper exports 2024-08-19 11:09:02 +02:00
Makefile kbuild: change working directory to external module directory with M= 2024-11-28 08:10:23 +09:00