]> www.infradead.org Git - nvme.git/commit
kbuild: change working directory to external module directory with M=
authorMasahiro Yamada <masahiroy@kernel.org>
Sun, 10 Nov 2024 01:34:33 +0000 (10:34 +0900)
committerMasahiro Yamada <masahiroy@kernel.org>
Wed, 27 Nov 2024 23:10:23 +0000 (08:10 +0900)
commit13b25489b6f8bd73ed65f07928f7c27a481f1820
treee9812994c22644da000e94af4c2e343101b469de
parentd17113601909eb43c29cbb3449fd49db427ff6be
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>
Documentation/dev-tools/coccinelle.rst
Documentation/kbuild/makefiles.rst
Makefile
rust/Makefile
scripts/Makefile.build
scripts/Makefile.clean
scripts/Makefile.compiler
scripts/Makefile.modpost
scripts/coccicheck
scripts/nsdeps
scripts/package/install-extmod-build