diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/kbuild/makefiles.rst | 5 | ||||
| -rw-r--r-- | Documentation/kbuild/modules.rst | 7 | ||||
| -rw-r--r-- | Documentation/kbuild/reproducible-builds.rst | 13 |
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 |