Commit 2d00aee2 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'kbuild-fixes-v5.4' of... 

Merge tag 'kbuild-fixes-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - remove unneeded ar-option and KBUILD_ARFLAGS

 - remove long-deprecated SUBDIRS

 - fix modpost to suppress false-positive warnings for UML builds

 - fix namespace.pl to handle relative paths to ${objtree}, ${srctree}

 - make setlocalversion work for /bin/sh

 - make header archive reproducible

 - fix some Makefiles and documents

* tag 'kbuild-fixes-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kheaders: make headers archive reproducible
  kbuild: update compile-test header list for v5.4-rc2
  kbuild: two minor updates for Documentation/kbuild/modules.rst
  scripts/setlocalversion: clear local variable to make it work for sh
  namespace: fix namespace.pl script to support relative paths
  video/logo: do not generate unneeded logo C files
  video/logo: remove unneeded *.o pattern from clean-files
  integrity: remove pointless subdir-$(CONFIG_...)
  integrity: remove unneeded, broken attempt to add -fshort-wchar
  modpost: fix static EXPORT_SYMBOL warnings for UML build
  kbuild: correct formatting of header in kbuild module docs
  kbuild: remove SUBDIRS support
  kbuild: remove ar-option and KBUILD_ARFLAGS
parents 126195c9 86cdd2fd

Documentation/kbuild/makefiles.rst

+0 −5
Original line number Diff line number Diff line
@@ -954,11 +954,6 @@ When kbuild executes, the following steps are followed (roughly): 


	From commandline LDFLAGS_MODULE shall be used (see kbuild.txt).



    KBUILD_ARFLAGS   Options for $(AR) when creating archives



	$(KBUILD_ARFLAGS) set by the top level Makefile to "D" (deterministic

	mode) if this option is supported by $(AR).



    KBUILD_LDS



	The linker script with full path. Assigned by the top-level Makefile.

Documentation/kbuild/modules.rst

+4 −3
Original line number Diff line number Diff line
@@ -498,10 +498,11 @@ build. 
	will be written containing all exported symbols that were not

	defined in the kernel.



--- 6.3 Symbols From Another External Module

6.3 Symbols From Another External Module

----------------------------------------



	Sometimes, an external module uses exported symbols from

	another external module. kbuild needs to have full knowledge of

	another external module. Kbuild needs to have full knowledge of

	all symbols to avoid spitting out warnings about undefined

	symbols. Three solutions exist for this situation.
@@ -521,7 +522,7 @@ build. 
		The top-level kbuild file would then look like::



			#./Kbuild (or ./Makefile):

				obj-y := foo/ bar/

				obj-m := foo/ bar/



		And executing::

Documentation/kbuild/reproducible-builds.rst

+9 −4
Original line number Diff line number Diff line
@@ -16,16 +16,21 @@ the kernel may be unreproducible, and how to avoid them. 
Timestamps

----------



The kernel embeds a timestamp in two places:

The kernel embeds timestamps in three places:



* The version string exposed by ``uname()`` and included in

  ``/proc/version``



* File timestamps in the embedded initramfs



By default the timestamp is the current time.  This must be overridden

using the `KBUILD_BUILD_TIMESTAMP`_ variable.  If you are building

from a git commit, you could use its commit date.

* If enabled via ``CONFIG_IKHEADERS``, file timestamps of kernel

  headers embedded in the kernel or respective module,

  exposed via ``/sys/kernel/kheaders.tar.xz``



By default the timestamp is the current time and in the case of

``kheaders`` the various files' modification times. This must

be overridden using the `KBUILD_BUILD_TIMESTAMP`_ variable.

If you are building from a git commit, you could use its commit date.



The kernel does *not* use the ``__DATE__`` and ``__TIME__`` macros,

and enables warnings if they are used.  If you incorporate external

Makefile

+2 −22
Original line number Diff line number Diff line
@@ -206,24 +206,8 @@ ifndef KBUILD_CHECKSRC 
  KBUILD_CHECKSRC = 0

endif



# Use make M=dir to specify directory of external module to build

# Old syntax make ... SUBDIRS=$PWD is still supported

# Setting the environment variable KBUILD_EXTMOD take precedence

ifdef SUBDIRS

  $(warning ================= WARNING ================)

  $(warning 'SUBDIRS' will be removed after Linux 5.3)

  $(warning )

  $(warning If you are building an individual subdirectory)

  $(warning in the kernel tree, you can do like this:)

  $(warning $$ make path/to/dir/you/want/to/build/)

  $(warning (Do not forget the trailing slash))

  $(warning )

  $(warning If you are building an external module,)

  $(warning Please use 'M=' or 'KBUILD_EXTMOD' instead)

  $(warning ==========================================)

  KBUILD_EXTMOD ?= $(SUBDIRS)

endif



# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the

# directory of external module to build. Setting M= takes precedence.

ifeq ("$(origin M)", "command line")

  KBUILD_EXTMOD := $(M)

endif
@@ -498,7 +482,6 @@ export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN 
export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE

export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE

export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL

export KBUILD_ARFLAGS



# Files to ignore in find ... statements
@@ -914,9 +897,6 @@ ifdef CONFIG_RETPOLINE 
KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)

endif



# use the deterministic mode of AR if available

KBUILD_ARFLAGS := $(call ar-option,D)



include scripts/Makefile.kasan

include scripts/Makefile.extrawarn

include scripts/Makefile.ubsan

arch/powerpc/boot/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -50,7 +50,7 @@ endif 


BOOTAFLAGS	:= -D__ASSEMBLY__ $(BOOTCFLAGS) -nostdinc



BOOTARFLAGS	:= -cr$(KBUILD_ARFLAGS)

BOOTARFLAGS	:= -crD



ifdef CONFIG_CC_IS_CLANG

BOOTCFLAGS += $(CLANG_FLAGS)

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