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authorLinus Torvalds <torvalds@linux-foundation.org>2019-10-05 12:56:59 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-10-05 12:56:59 -0700
commit2d00aee21a5d4966e086d98f9d710afb92fb14e8 (patch)
tree7e35b06f7834c4cdca1e1c320d3d9097c97ff85f /Documentation
parent126195c972a2adba8cae12a65cdee155440a4525 (diff)
parent86cdd2fdc4e39c388d39c7ba2396d1a9dfd66226 (diff)
downloadlinux-2d00aee21a5d4966e086d98f9d710afb92fb14e8.tar.gz
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
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/kbuild/makefiles.rst5
-rw-r--r--Documentation/kbuild/modules.rst7
-rw-r--r--Documentation/kbuild/reproducible-builds.rst13
3 files changed, 13 insertions, 12 deletions
diff --git a/Documentation/kbuild/makefiles.rst b/Documentation/kbuild/makefiles.rst
index 6ba9d5365ff3..b89c88168d6a 100644
--- a/Documentation/kbuild/makefiles.rst
+++ b/Documentation/kbuild/makefiles.rst
@@ -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.
diff --git a/Documentation/kbuild/modules.rst b/Documentation/kbuild/modules.rst
index d2ae799237fd..774a998dcf37 100644
--- a/Documentation/kbuild/modules.rst
+++ b/Documentation/kbuild/modules.rst
@@ -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::
 
diff --git a/Documentation/kbuild/reproducible-builds.rst b/Documentation/kbuild/reproducible-builds.rst
index ab92e98c89c8..503393854e2e 100644
--- a/Documentation/kbuild/reproducible-builds.rst
+++ b/Documentation/kbuild/reproducible-builds.rst
@@ -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