Commit 8e2499487236 for kernel

commit 8e24994872361212531a952c93adb01c485148f1
Author: Nathan Chancellor <nathan@kernel.org>
Date:   Fri Jan 30 14:37:47 2026 -0700

    kbuild: Do not run kernel-doc when building external modules

    After commit 778b8ebe5192 ("docs: Move the python libraries to
    tools/lib/python"), building an external module with any value of W=
    against the output of install-extmod-build fails with:

      $ make -C /usr/lib/modules/6.19.0-rc7-00108-g4d310797262f/build M=$PWD W=1
      make: Entering directory '/usr/lib/modules/6.19.0-rc7-00108-g4d310797262f/build'
      make[1]: Entering directory '...'
        CC [M] ...
      Traceback (most recent call last):
        File "/usr/lib/modules/6.19.0-rc7-00108-g4d310797262f/build/scripts/kernel-doc.py", line 339, in <module>
          main()
          ~~~~^^
        File "/usr/lib/modules/6.19.0-rc7-00108-g4d310797262f/build/scripts/kernel-doc.py", line 295, in main
          from kdoc.kdoc_files import KernelFiles             # pylint: disable=C0415
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
      ModuleNotFoundError: No module named 'kdoc'

    scripts/lib was included in the build directory from find_in_scripts but
    after the move to tools/lib/python, it is no longer included, breaking
    kernel-doc.py.

    Commit eba6ffd126cd ("docs: kdoc: move kernel-doc to tools/docs") breaks
    this even further by moving kernel-doc outside of scripts as well, so it
    cannot be found when called by cmd_checkdoc.

      $ make -C /usr/lib/modules/6.19.0-rc7-next-20260130/build M=$PWD W=1
      make: Entering directory '/usr/lib/modules/6.19.0-rc7-next-20260130/build'
      make[1]: Entering directory '...'
        CC [M]  ...
      python3: can't open file '/usr/lib/modules/6.19.0-rc7-next-20260130/build/tools/docs/kernel-doc': [Errno 2] No such file or directory

    While kernel-doc could be useful for external modules, it is more useful
    for in-tree documentation that will be build and included in htmldocs.
    Rather than including it in install-extmod-build, just skip running
    kernel-doc for the external module build.

    Cc: stable@vger.kernel.org
    Fixes: 778b8ebe5192 ("docs: Move the python libraries to tools/lib/python")
    Reported-by: Rong Zhang <i@rong.moe>
    Closes: https://lore.kernel.org/20260129175321.415295-1-i@rong.moe/
    Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
    Signed-off-by: Nathan Chancellor <nathan@kernel.org>
    Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
    Link: https://patch.msgid.link/20260130-kbuild-skip-kernel-doc-extmod-v1-1-58443d60131a@kernel.org
    Reviewed-by: Nicolas Schier <nsc@kernel.org>
    Signed-off-by: Nicolas Schier <nsc@kernel.org>

diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 5037f4715d74..f01d7957edf7 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -166,11 +166,13 @@ else ifeq ($(KBUILD_CHECKSRC),2)
         cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $<
 endif

+ifeq ($(KBUILD_EXTMOD),)
 ifneq ($(KBUILD_EXTRA_WARN),)
   cmd_checkdoc = PYTHONDONTWRITEBYTECODE=1 $(PYTHON3) $(KERNELDOC) -none $(KDOCFLAGS) \
         $(if $(findstring 2, $(KBUILD_EXTRA_WARN)), -Wall) \
         $<
 endif
+endif

 # Compile C sources (.c)
 # ---------------------------------------------------------------------------