275 lines
7.7 KiB
ReStructuredText
275 lines
7.7 KiB
ReStructuredText
|
======
|
||
|
Kbuild
|
||
|
======
|
||
|
|
||
|
|
||
|
Output files
|
||
|
============
|
||
|
|
||
|
modules.order
|
||
|
-------------
|
||
|
This file records the order in which modules appear in Makefiles. This
|
||
|
is used by modprobe to deterministically resolve aliases that match
|
||
|
multiple modules.
|
||
|
|
||
|
modules.builtin
|
||
|
---------------
|
||
|
This file lists all modules that are built into the kernel. This is used
|
||
|
by modprobe to not fail when trying to load something builtin.
|
||
|
|
||
|
modules.builtin.modinfo
|
||
|
--------------------------------------------------
|
||
|
This file contains modinfo from all modules that are built into the kernel.
|
||
|
Unlike modinfo of a separate module, all fields are prefixed with module name.
|
||
|
|
||
|
|
||
|
Environment variables
|
||
|
=====================
|
||
|
|
||
|
KCPPFLAGS
|
||
|
---------
|
||
|
Additional options to pass when preprocessing. The preprocessing options
|
||
|
will be used in all cases where kbuild does preprocessing including
|
||
|
building C files and assembler files.
|
||
|
|
||
|
KAFLAGS
|
||
|
-------
|
||
|
Additional options to the assembler (for built-in and modules).
|
||
|
|
||
|
AFLAGS_MODULE
|
||
|
-------------
|
||
|
Additional module specific options to use for $(AS).
|
||
|
|
||
|
AFLAGS_KERNEL
|
||
|
-------------
|
||
|
Additional options for $(AS) when used for assembler
|
||
|
code for code that is compiled as built-in.
|
||
|
|
||
|
KCFLAGS
|
||
|
-------
|
||
|
Additional options to the C compiler (for built-in and modules).
|
||
|
|
||
|
CFLAGS_KERNEL
|
||
|
-------------
|
||
|
Additional options for $(CC) when used to compile
|
||
|
code that is compiled as built-in.
|
||
|
|
||
|
CFLAGS_MODULE
|
||
|
-------------
|
||
|
Additional module specific options to use for $(CC).
|
||
|
|
||
|
LDFLAGS_MODULE
|
||
|
--------------
|
||
|
Additional options used for $(LD) when linking modules.
|
||
|
|
||
|
HOSTCFLAGS
|
||
|
----------
|
||
|
Additional flags to be passed to $(HOSTCC) when building host programs.
|
||
|
|
||
|
HOSTCXXFLAGS
|
||
|
------------
|
||
|
Additional flags to be passed to $(HOSTCXX) when building host programs.
|
||
|
|
||
|
HOSTLDFLAGS
|
||
|
-----------
|
||
|
Additional flags to be passed when linking host programs.
|
||
|
|
||
|
HOSTLDLIBS
|
||
|
----------
|
||
|
Additional libraries to link against when building host programs.
|
||
|
|
||
|
KBUILD_KCONFIG
|
||
|
--------------
|
||
|
Set the top-level Kconfig file to the value of this environment
|
||
|
variable. The default name is "Kconfig".
|
||
|
|
||
|
KBUILD_VERBOSE
|
||
|
--------------
|
||
|
Set the kbuild verbosity. Can be assigned same values as "V=...".
|
||
|
|
||
|
See make help for the full list.
|
||
|
|
||
|
Setting "V=..." takes precedence over KBUILD_VERBOSE.
|
||
|
|
||
|
KBUILD_EXTMOD
|
||
|
-------------
|
||
|
Set the directory to look for the kernel source when building external
|
||
|
modules.
|
||
|
|
||
|
Setting "M=..." takes precedence over KBUILD_EXTMOD.
|
||
|
|
||
|
KBUILD_OUTPUT
|
||
|
-------------
|
||
|
Specify the output directory when building the kernel.
|
||
|
|
||
|
The output directory can also be specified using "O=...".
|
||
|
|
||
|
Setting "O=..." takes precedence over KBUILD_OUTPUT.
|
||
|
|
||
|
KBUILD_DEBARCH
|
||
|
--------------
|
||
|
For the deb-pkg target, allows overriding the normal heuristics deployed by
|
||
|
deb-pkg. Normally deb-pkg attempts to guess the right architecture based on
|
||
|
the UTS_MACHINE variable, and on some architectures also the kernel config.
|
||
|
The value of KBUILD_DEBARCH is assumed (not checked) to be a valid Debian
|
||
|
architecture.
|
||
|
|
||
|
ARCH
|
||
|
----
|
||
|
Set ARCH to the architecture to be built.
|
||
|
|
||
|
In most cases the name of the architecture is the same as the
|
||
|
directory name found in the arch/ directory.
|
||
|
|
||
|
But some architectures such as x86 and sparc have aliases.
|
||
|
|
||
|
- x86: i386 for 32 bit, x86_64 for 64 bit
|
||
|
- sh: sh for 32 bit, sh64 for 64 bit
|
||
|
- sparc: sparc32 for 32 bit, sparc64 for 64 bit
|
||
|
|
||
|
CROSS_COMPILE
|
||
|
-------------
|
||
|
Specify an optional fixed part of the binutils filename.
|
||
|
CROSS_COMPILE can be a part of the filename or the full path.
|
||
|
|
||
|
CROSS_COMPILE is also used for ccache in some setups.
|
||
|
|
||
|
CF
|
||
|
--
|
||
|
Additional options for sparse.
|
||
|
|
||
|
CF is often used on the command-line like this::
|
||
|
|
||
|
make CF=-Wbitwise C=2
|
||
|
|
||
|
INSTALL_PATH
|
||
|
------------
|
||
|
INSTALL_PATH specifies where to place the updated kernel and system map
|
||
|
images. Default is /boot, but you can set it to other values.
|
||
|
|
||
|
INSTALLKERNEL
|
||
|
-------------
|
||
|
Install script called when using "make install".
|
||
|
The default name is "installkernel".
|
||
|
|
||
|
The script will be called with the following arguments:
|
||
|
- $1 - kernel version
|
||
|
- $2 - kernel image file
|
||
|
- $3 - kernel map file
|
||
|
- $4 - default install path (use root directory if blank)
|
||
|
|
||
|
The implementation of "make install" is architecture specific
|
||
|
and it may differ from the above.
|
||
|
|
||
|
INSTALLKERNEL is provided to enable the possibility to
|
||
|
specify a custom installer when cross compiling a kernel.
|
||
|
|
||
|
MODLIB
|
||
|
------
|
||
|
Specify where to install modules.
|
||
|
The default value is::
|
||
|
|
||
|
$(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
|
||
|
|
||
|
The value can be overridden in which case the default value is ignored.
|
||
|
|
||
|
INSTALL_MOD_PATH
|
||
|
----------------
|
||
|
INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
|
||
|
relocations required by build roots. This is not defined in the
|
||
|
makefile but the argument can be passed to make if needed.
|
||
|
|
||
|
INSTALL_MOD_STRIP
|
||
|
-----------------
|
||
|
INSTALL_MOD_STRIP, if defined, will cause modules to be
|
||
|
stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
|
||
|
the default option --strip-debug will be used. Otherwise,
|
||
|
INSTALL_MOD_STRIP value will be used as the options to the strip command.
|
||
|
|
||
|
INSTALL_HDR_PATH
|
||
|
----------------
|
||
|
INSTALL_HDR_PATH specifies where to install user space headers when
|
||
|
executing "make headers_*".
|
||
|
|
||
|
The default value is::
|
||
|
|
||
|
$(objtree)/usr
|
||
|
|
||
|
$(objtree) is the directory where output files are saved.
|
||
|
The output directory is often set using "O=..." on the commandline.
|
||
|
|
||
|
The value can be overridden in which case the default value is ignored.
|
||
|
|
||
|
KBUILD_ABS_SRCTREE
|
||
|
--------------------------------------------------
|
||
|
Kbuild uses a relative path to point to the tree when possible. For instance,
|
||
|
when building in the source tree, the source tree path is '.'
|
||
|
|
||
|
Setting this flag requests Kbuild to use absolute path to the source tree.
|
||
|
There are some useful cases to do so, like when generating tag files with
|
||
|
absolute path entries etc.
|
||
|
|
||
|
KBUILD_SIGN_PIN
|
||
|
---------------
|
||
|
This variable allows a passphrase or PIN to be passed to the sign-file
|
||
|
utility when signing kernel modules, if the private key requires such.
|
||
|
|
||
|
KBUILD_MODPOST_WARN
|
||
|
-------------------
|
||
|
KBUILD_MODPOST_WARN can be set to avoid errors in case of undefined
|
||
|
symbols in the final module linking stage. It changes such errors
|
||
|
into warnings.
|
||
|
|
||
|
KBUILD_MODPOST_NOFINAL
|
||
|
----------------------
|
||
|
KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
|
||
|
This is solely useful to speed up test compiles.
|
||
|
|
||
|
KBUILD_EXTRA_SYMBOLS
|
||
|
--------------------
|
||
|
For modules that use symbols from other modules.
|
||
|
See more details in modules.txt.
|
||
|
|
||
|
ALLSOURCE_ARCHS
|
||
|
---------------
|
||
|
For tags/TAGS/cscope targets, you can specify more than one arch
|
||
|
to be included in the databases, separated by blank space. E.g.::
|
||
|
|
||
|
$ make ALLSOURCE_ARCHS="x86 mips arm" tags
|
||
|
|
||
|
To get all available archs you can also specify all. E.g.::
|
||
|
|
||
|
$ make ALLSOURCE_ARCHS=all tags
|
||
|
|
||
|
KBUILD_ENABLE_EXTRA_GCC_CHECKS
|
||
|
------------------------------
|
||
|
If enabled over the make command line with "W=1", it turns on additional
|
||
|
gcc -W... options for more extensive build-time checking.
|
||
|
|
||
|
KBUILD_BUILD_TIMESTAMP
|
||
|
----------------------
|
||
|
Setting this to a date string overrides the timestamp used in the
|
||
|
UTS_VERSION definition (uname -v in the running kernel). The value has to
|
||
|
be a string that can be passed to date -d. The default value
|
||
|
is the output of the date command at one point during build.
|
||
|
|
||
|
KBUILD_BUILD_USER, KBUILD_BUILD_HOST
|
||
|
------------------------------------
|
||
|
These two variables allow to override the user@host string displayed during
|
||
|
boot and in /proc/version. The default value is the output of the commands
|
||
|
whoami and host, respectively.
|
||
|
|
||
|
KBUILD_LDS
|
||
|
----------
|
||
|
The linker script with full path. Assigned by the top-level Makefile.
|
||
|
|
||
|
KBUILD_VMLINUX_OBJS
|
||
|
-------------------
|
||
|
All object files for vmlinux. They are linked to vmlinux in the same
|
||
|
order as listed in KBUILD_VMLINUX_OBJS.
|
||
|
|
||
|
KBUILD_VMLINUX_LIBS
|
||
|
-------------------
|
||
|
All .a "lib" files for vmlinux. KBUILD_VMLINUX_OBJS and KBUILD_VMLINUX_LIBS
|
||
|
together specify all the object files used to link vmlinux.
|