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Commit cd238eff authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab Committed by Jonathan Corbet
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docs: kbuild: convert docs to ReST and rename to *.rst 

The kbuild documentation clearly shows that the documents
there are written at different times: some use markdown,
some use their own peculiar logic to split sections.

Convert everything to ReST without affecting too much
the author's style and avoiding adding uneeded markups.

The conversion is actually:
  - add blank lines and identation in order to identify paragraphs;
  - fix tables markups;
  - add some lists markups;
  - mark literal blocks;
  - adjust title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: default avatarJonathan Corbet <corbet@lwn.net>
parent d7b461c5
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Showing with 846 additions and 567 deletions
Documentation/admin-guide/README.rst
View file @ cd238eff
...@@ -227,7 +227,7 @@ Configuring the kernel ...@@ -227,7 +227,7 @@ Configuring the kernel
"make tinyconfig" Configure the tiniest possible kernel. "make tinyconfig" Configure the tiniest possible kernel.
You can find more information on using the Linux kernel config tools You can find more information on using the Linux kernel config tools
in Documentation/kbuild/kconfig.txt. in Documentation/kbuild/kconfig.rst.
- NOTES on ``make config``: - NOTES on ``make config``:
......
Documentation/kbuild/headers_install.txt → Documentation/kbuild/headers_install.rst
View file @ cd238eff
=============================================
Exporting kernel headers for use by userspace Exporting kernel headers for use by userspace
============================================= =============================================
...@@ -22,14 +23,14 @@ older kernel. ...@@ -22,14 +23,14 @@ older kernel.
The "make headers_install" command can be run in the top level directory of the The "make headers_install" command can be run in the top level directory of the
kernel source code (or using a standard out-of-tree build). It takes two kernel source code (or using a standard out-of-tree build). It takes two
optional arguments: optional arguments::
make headers_install ARCH=i386 INSTALL_HDR_PATH=/usr make headers_install ARCH=i386 INSTALL_HDR_PATH=/usr
ARCH indicates which architecture to produce headers for, and defaults to the ARCH indicates which architecture to produce headers for, and defaults to the
current architecture. The linux/asm directory of the exported kernel headers current architecture. The linux/asm directory of the exported kernel headers
is platform-specific, to see a complete list of supported architectures use is platform-specific, to see a complete list of supported architectures use
the command: the command::
ls -d include/asm-* | sed 's/.*-//' ls -d include/asm-* | sed 's/.*-//'
......
Documentation/kbuild/index.rst 0 → 100644
View file @ cd238eff
:orphan:
===================
Kernel Build System
===================
.. toctree::
:maxdepth: 1
kconfig-language
kconfig-macro-language
kbuild
kconfig
makefiles
modules
headers_install
issues
.. only:: subproject and html
Indices
=======
* :ref:`genindex`
Documentation/kbuild/issues.rst 0 → 100644
View file @ cd238eff
Recursion issue #1
------------------
.. include:: Kconfig.recursion-issue-01
:literal:
Recursion issue #2
------------------
.. include:: Kconfig.recursion-issue-02
:literal:
Documentation/kbuild/kbuild.txt → Documentation/kbuild/kbuild.rst
View file @ cd238eff
======
Kbuild
======
Output files Output files
============
modules.order modules.order
-------------------------------------------------- -------------
This file records the order in which modules appear in Makefiles. This This file records the order in which modules appear in Makefiles. This
is used by modprobe to deterministically resolve aliases that match is used by modprobe to deterministically resolve aliases that match
multiple modules. multiple modules.
modules.builtin modules.builtin
-------------------------------------------------- ---------------
This file lists all modules that are built into the kernel. This is used 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. by modprobe to not fail when trying to load something builtin.
...@@ -18,84 +24,90 @@ Unlike modinfo of a separate module, all fields are prefixed with module name. ...@@ -18,84 +24,90 @@ Unlike modinfo of a separate module, all fields are prefixed with module name.
Environment variables Environment variables
=====================
KCPPFLAGS KCPPFLAGS
-------------------------------------------------- ---------
Additional options to pass when preprocessing. The preprocessing options Additional options to pass when preprocessing. The preprocessing options
will be used in all cases where kbuild does preprocessing including will be used in all cases where kbuild does preprocessing including
building C files and assembler files. building C files and assembler files.
KAFLAGS KAFLAGS
-------------------------------------------------- -------
Additional options to the assembler (for built-in and modules). Additional options to the assembler (for built-in and modules).
AFLAGS_MODULE AFLAGS_MODULE
-------------------------------------------------- -------------
Additional module specific options to use for $(AS). Additional module specific options to use for $(AS).
AFLAGS_KERNEL AFLAGS_KERNEL
-------------------------------------------------- -------------
Additional options for $(AS) when used for assembler Additional options for $(AS) when used for assembler
code for code that is compiled as built-in. code for code that is compiled as built-in.
KCFLAGS KCFLAGS
-------------------------------------------------- -------
Additional options to the C compiler (for built-in and modules). Additional options to the C compiler (for built-in and modules).
CFLAGS_KERNEL CFLAGS_KERNEL
-------------------------------------------------- -------------
Additional options for $(CC) when used to compile Additional options for $(CC) when used to compile
code that is compiled as built-in. code that is compiled as built-in.
CFLAGS_MODULE CFLAGS_MODULE
-------------------------------------------------- -------------
Additional module specific options to use for $(CC). Additional module specific options to use for $(CC).
LDFLAGS_MODULE LDFLAGS_MODULE
-------------------------------------------------- --------------
Additional options used for $(LD) when linking modules. Additional options used for $(LD) when linking modules.
HOSTCFLAGS HOSTCFLAGS
-------------------------------------------------- ----------
Additional flags to be passed to $(HOSTCC) when building host programs. Additional flags to be passed to $(HOSTCC) when building host programs.
HOSTCXXFLAGS HOSTCXXFLAGS
-------------------------------------------------- ------------
Additional flags to be passed to $(HOSTCXX) when building host programs. Additional flags to be passed to $(HOSTCXX) when building host programs.
HOSTLDFLAGS HOSTLDFLAGS
-------------------------------------------------- -----------
Additional flags to be passed when linking host programs. Additional flags to be passed when linking host programs.
HOSTLDLIBS HOSTLDLIBS
-------------------------------------------------- ----------
Additional libraries to link against when building host programs. Additional libraries to link against when building host programs.
KBUILD_KCONFIG KBUILD_KCONFIG
-------------------------------------------------- --------------
Set the top-level Kconfig file to the value of this environment Set the top-level Kconfig file to the value of this environment
variable. The default name is "Kconfig". variable. The default name is "Kconfig".
KBUILD_VERBOSE KBUILD_VERBOSE
-------------------------------------------------- --------------
Set the kbuild verbosity. Can be assigned same values as "V=...". Set the kbuild verbosity. Can be assigned same values as "V=...".
See make help for the full list. See make help for the full list.
Setting "V=..." takes precedence over KBUILD_VERBOSE. Setting "V=..." takes precedence over KBUILD_VERBOSE.
KBUILD_EXTMOD KBUILD_EXTMOD
-------------------------------------------------- -------------
Set the directory to look for the kernel source when building external Set the directory to look for the kernel source when building external
modules. modules.
Setting "M=..." takes precedence over KBUILD_EXTMOD. Setting "M=..." takes precedence over KBUILD_EXTMOD.
KBUILD_OUTPUT KBUILD_OUTPUT
-------------------------------------------------- -------------
Specify the output directory when building the kernel. Specify the output directory when building the kernel.
The output directory can also be specified using "O=...". The output directory can also be specified using "O=...".
Setting "O=..." takes precedence over KBUILD_OUTPUT. Setting "O=..." takes precedence over KBUILD_OUTPUT.
KBUILD_DEBARCH KBUILD_DEBARCH
-------------------------------------------------- --------------
For the deb-pkg target, allows overriding the normal heuristics deployed by 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 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 UTS_MACHINE variable, and on some architectures also the kernel config.
...@@ -103,44 +115,48 @@ The value of KBUILD_DEBARCH is assumed (not checked) to be a valid Debian ...@@ -103,44 +115,48 @@ The value of KBUILD_DEBARCH is assumed (not checked) to be a valid Debian
architecture. architecture.
ARCH ARCH
-------------------------------------------------- ----
Set ARCH to the architecture to be built. Set ARCH to the architecture to be built.
In most cases the name of the architecture is the same as the In most cases the name of the architecture is the same as the
directory name found in the arch/ directory. directory name found in the arch/ directory.
But some architectures such as x86 and sparc have aliases. 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 - x86: i386 for 32 bit, x86_64 for 64 bit
sparc: sparc32 for 32 bit, sparc64 for 64 bit - sh: sh for 32 bit, sh64 for 64 bit
- sparc: sparc32 for 32 bit, sparc64 for 64 bit
CROSS_COMPILE CROSS_COMPILE
-------------------------------------------------- -------------
Specify an optional fixed part of the binutils filename. Specify an optional fixed part of the binutils filename.
CROSS_COMPILE can be a part of the filename or the full path. CROSS_COMPILE can be a part of the filename or the full path.
CROSS_COMPILE is also used for ccache in some setups. CROSS_COMPILE is also used for ccache in some setups.
CF CF
-------------------------------------------------- --
Additional options for sparse. Additional options for sparse.
CF is often used on the command-line like this:
CF is often used on the command-line like this::
make CF=-Wbitwise C=2 make CF=-Wbitwise C=2
INSTALL_PATH INSTALL_PATH
-------------------------------------------------- ------------
INSTALL_PATH specifies where to place the updated kernel and system map INSTALL_PATH specifies where to place the updated kernel and system map
images. Default is /boot, but you can set it to other values. images. Default is /boot, but you can set it to other values.
INSTALLKERNEL INSTALLKERNEL
-------------------------------------------------- -------------
Install script called when using "make install". Install script called when using "make install".
The default name is "installkernel". The default name is "installkernel".
The script will be called with the following arguments: The script will be called with the following arguments:
$1 - kernel version - $1 - kernel version
$2 - kernel image file - $2 - kernel image file
$3 - kernel map file - $3 - kernel map file
$4 - default install path (use root directory if blank) - $4 - default install path (use root directory if blank)
The implementation of "make install" is architecture specific The implementation of "make install" is architecture specific
and it may differ from the above. and it may differ from the above.
...@@ -149,32 +165,33 @@ INSTALLKERNEL is provided to enable the possibility to ...@@ -149,32 +165,33 @@ INSTALLKERNEL is provided to enable the possibility to
specify a custom installer when cross compiling a kernel. specify a custom installer when cross compiling a kernel.
MODLIB MODLIB
-------------------------------------------------- ------
Specify where to install modules. Specify where to install modules.
The default value is: The default value is::
$(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE) $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
The value can be overridden in which case the default value is ignored. The value can be overridden in which case the default value is ignored.
INSTALL_MOD_PATH INSTALL_MOD_PATH
-------------------------------------------------- ----------------
INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
relocations required by build roots. This is not defined in the relocations required by build roots. This is not defined in the
makefile but the argument can be passed to make if needed. makefile but the argument can be passed to make if needed.
INSTALL_MOD_STRIP INSTALL_MOD_STRIP
-------------------------------------------------- -----------------
INSTALL_MOD_STRIP, if defined, will cause modules to be INSTALL_MOD_STRIP, if defined, will cause modules to be
stripped after they are installed. If INSTALL_MOD_STRIP is '1', then stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
the default option --strip-debug will be used. Otherwise, the default option --strip-debug will be used. Otherwise,
INSTALL_MOD_STRIP value will be used as the options to the strip command. INSTALL_MOD_STRIP value will be used as the options to the strip command.
INSTALL_HDR_PATH INSTALL_HDR_PATH
-------------------------------------------------- ----------------
INSTALL_HDR_PATH specifies where to install user space headers when INSTALL_HDR_PATH specifies where to install user space headers when
executing "make headers_*". executing "make headers_*".
The default value is:
The default value is::
$(objtree)/usr $(objtree)/usr
...@@ -184,65 +201,65 @@ The output directory is often set using "O=..." on the commandline. ...@@ -184,65 +201,65 @@ The output directory is often set using "O=..." on the commandline.
The value can be overridden in which case the default value is ignored. The value can be overridden in which case the default value is ignored.
KBUILD_SIGN_PIN KBUILD_SIGN_PIN
-------------------------------------------------- ---------------
This variable allows a passphrase or PIN to be passed to the sign-file 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. utility when signing kernel modules, if the private key requires such.
KBUILD_MODPOST_WARN KBUILD_MODPOST_WARN
-------------------------------------------------- -------------------
KBUILD_MODPOST_WARN can be set to avoid errors in case of undefined KBUILD_MODPOST_WARN can be set to avoid errors in case of undefined
symbols in the final module linking stage. It changes such errors symbols in the final module linking stage. It changes such errors
into warnings. into warnings.
KBUILD_MODPOST_NOFINAL KBUILD_MODPOST_NOFINAL
-------------------------------------------------- ----------------------
KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules. KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
This is solely useful to speed up test compiles. This is solely useful to speed up test compiles.
KBUILD_EXTRA_SYMBOLS KBUILD_EXTRA_SYMBOLS
-------------------------------------------------- --------------------
For modules that use symbols from other modules. For modules that use symbols from other modules.
See more details in modules.txt. See more details in modules.txt.
ALLSOURCE_ARCHS ALLSOURCE_ARCHS
-------------------------------------------------- ---------------
For tags/TAGS/cscope targets, you can specify more than one arch For tags/TAGS/cscope targets, you can specify more than one arch
to be included in the databases, separated by blank space. E.g.: to be included in the databases, separated by blank space. E.g.::
$ make ALLSOURCE_ARCHS="x86 mips arm" tags $ make ALLSOURCE_ARCHS="x86 mips arm" tags
To get all available archs you can also specify all. E.g.: To get all available archs you can also specify all. E.g.::
$ make ALLSOURCE_ARCHS=all tags $ make ALLSOURCE_ARCHS=all tags
KBUILD_ENABLE_EXTRA_GCC_CHECKS KBUILD_ENABLE_EXTRA_GCC_CHECKS
-------------------------------------------------- ------------------------------
If enabled over the make command line with "W=1", it turns on additional If enabled over the make command line with "W=1", it turns on additional
gcc -W... options for more extensive build-time checking. gcc -W... options for more extensive build-time checking.
KBUILD_BUILD_TIMESTAMP KBUILD_BUILD_TIMESTAMP
-------------------------------------------------- ----------------------
Setting this to a date string overrides the timestamp used in the 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 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 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. is the output of the date command at one point during build.
KBUILD_BUILD_USER, KBUILD_BUILD_HOST KBUILD_BUILD_USER, KBUILD_BUILD_HOST
-------------------------------------------------- ------------------------------------
These two variables allow to override the user@host string displayed during 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 boot and in /proc/version. The default value is the output of the commands
whoami and host, respectively. whoami and host, respectively.
KBUILD_LDS KBUILD_LDS
-------------------------------------------------- ----------
The linker script with full path. Assigned by the top-level Makefile. The linker script with full path. Assigned by the top-level Makefile.
KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_OBJS
-------------------------------------------------- -------------------
All object files for vmlinux. They are linked to vmlinux in the same All object files for vmlinux. They are linked to vmlinux in the same
order as listed in KBUILD_VMLINUX_OBJS. order as listed in KBUILD_VMLINUX_OBJS.
KBUILD_VMLINUX_LIBS KBUILD_VMLINUX_LIBS
-------------------------------------------------- -------------------
All .a "lib" files for vmlinux. KBUILD_VMLINUX_OBJS and 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. together specify all the object files used to link vmlinux.
Documentation/kbuild/kconfig-language.txt → Documentation/kbuild/kconfig-language.rst
View file @ cd238eff
================
Kconfig Language
================
Introduction Introduction
------------ ------------
The configuration database is a collection of configuration options The configuration database is a collection of configuration options
organized in a tree structure: organized in a tree structure::
+- Code maturity level options +- Code maturity level options
| +- Prompt for development and/or incomplete code/drivers | +- Prompt for development and/or incomplete code/drivers
...@@ -25,9 +29,9 @@ Menu entries ...@@ -25,9 +29,9 @@ Menu entries
------------ ------------
Most entries define a config option; all other entries help to organize Most entries define a config option; all other entries help to organize
them. A single configuration option is defined like this: them. A single configuration option is defined like this::
config MODVERSIONS config MODVERSIONS
bool "Set version information on all module symbols" bool "Set version information on all module symbols"
depends on MODULES depends on MODULES
help help
...@@ -52,10 +56,12 @@ applicable everywhere (see syntax). ...@@ -52,10 +56,12 @@ applicable everywhere (see syntax).
Every config option must have a type. There are only two basic types: Every config option must have a type. There are only two basic types:
tristate and string; the other types are based on these two. The type tristate and string; the other types are based on these two. The type
definition optionally accepts an input prompt, so these two examples definition optionally accepts an input prompt, so these two examples
are equivalent: are equivalent::
bool "Networking support" bool "Networking support"
and
and::
bool bool
prompt "Networking support" prompt "Networking support"
...@@ -98,8 +104,10 @@ applicable everywhere (see syntax). ...@@ -98,8 +104,10 @@ applicable everywhere (see syntax).
d) Hardware or infrastructure that everybody expects, such as CONFIG_NET d) Hardware or infrastructure that everybody expects, such as CONFIG_NET
or CONFIG_BLOCK. These are rare exceptions. or CONFIG_BLOCK. These are rare exceptions.
- type definition + default value: - type definition + default value::
"def_bool"/"def_tristate" <expr> ["if" <expr>] "def_bool"/"def_tristate" <expr> ["if" <expr>]
This is a shorthand notation for a type definition plus a value. This is a shorthand notation for a type definition plus a value.
Optionally dependencies for this default value can be added with "if". Optionally dependencies for this default value can be added with "if".
...@@ -107,11 +115,13 @@ applicable everywhere (see syntax). ...@@ -107,11 +115,13 @@ applicable everywhere (see syntax).
This defines a dependency for this menu entry. If multiple This defines a dependency for this menu entry. If multiple
dependencies are defined, they are connected with '&&'. Dependencies dependencies are defined, they are connected with '&&'. Dependencies
are applied to all other options within this menu entry (which also are applied to all other options within this menu entry (which also
accept an "if" expression), so these two examples are equivalent: accept an "if" expression), so these two examples are equivalent::
bool "foo" if BAR bool "foo" if BAR
default y if BAR default y if BAR
and
and::
depends on BAR depends on BAR
bool "foo" bool "foo"
default y default y
...@@ -124,6 +134,7 @@ applicable everywhere (see syntax). ...@@ -124,6 +134,7 @@ applicable everywhere (see syntax).
times, the limit is set to the largest selection. times, the limit is set to the largest selection.
Reverse dependencies can only be used with boolean or tristate Reverse dependencies can only be used with boolean or tristate
symbols. symbols.
Note: Note:
select should be used with care. select will force select should be used with care. select will force
a symbol to a value without visiting the dependencies. a symbol to a value without visiting the dependencies.
...@@ -139,7 +150,7 @@ applicable everywhere (see syntax). ...@@ -139,7 +150,7 @@ applicable everywhere (see syntax).
symbol except that the "implied" symbol's value may still be set to n symbol except that the "implied" symbol's value may still be set to n
from a direct dependency or with a visible prompt. from a direct dependency or with a visible prompt.
Given the following example: Given the following example::
config FOO config FOO
tristate tristate
...@@ -151,12 +162,14 @@ applicable everywhere (see syntax). ...@@ -151,12 +162,14 @@ applicable everywhere (see syntax).
The following values are possible: The following values are possible:
=== === ============= ==============
FOO BAR BAZ's default choice for BAZ FOO BAR BAZ's default choice for BAZ
--- --- ------------- -------------- === === ============= ==============
n y n N/m/y n y n N/m/y
m y m M/y/n m y m M/y/n
y y y Y/n y y y Y/n
y n * N y n * N
=== === ============= ==============
This is useful e.g. with multiple drivers that want to indicate their This is useful e.g. with multiple drivers that want to indicate their
ability to hook into a secondary subsystem while allowing the user to ability to hook into a secondary subsystem while allowing the user to
...@@ -208,9 +221,9 @@ Menu dependencies ...@@ -208,9 +221,9 @@ Menu dependencies
Dependencies define the visibility of a menu entry and can also reduce Dependencies define the visibility of a menu entry and can also reduce
the input range of tristate symbols. The tristate logic used in the the input range of tristate symbols. The tristate logic used in the
expressions uses one more state than normal boolean logic to express the expressions uses one more state than normal boolean logic to express the
module state. Dependency expressions have the following syntax: module state. Dependency expressions have the following syntax::
<expr> ::= <symbol> (1) <expr> ::= <symbol> (1)
<symbol> '=' <symbol> (2) <symbol> '=' <symbol> (2)
<symbol> '!=' <symbol> (3) <symbol> '!=' <symbol> (3)
<symbol1> '<' <symbol2> (4) <symbol1> '<' <symbol2> (4)
...@@ -255,15 +268,15 @@ Menu structure ...@@ -255,15 +268,15 @@ Menu structure
-------------- --------------
The position of a menu entry in the tree is determined in two ways. First The position of a menu entry in the tree is determined in two ways. First
it can be specified explicitly: it can be specified explicitly::
menu "Network device support" menu "Network device support"
depends on NET depends on NET
config NETDEVICES config NETDEVICES
... ...
endmenu endmenu
All entries within the "menu" ... "endmenu" block become a submenu of All entries within the "menu" ... "endmenu" block become a submenu of
"Network device support". All subentries inherit the dependencies from "Network device support". All subentries inherit the dependencies from
...@@ -275,17 +288,18 @@ dependencies. If a menu entry somehow depends on the previous entry, it ...@@ -275,17 +288,18 @@ dependencies. If a menu entry somehow depends on the previous entry, it
can be made a submenu of it. First, the previous (parent) symbol must can be made a submenu of it. First, the previous (parent) symbol must
be part of the dependency list and then one of these two conditions be part of the dependency list and then one of these two conditions
must be true: must be true:
- the child entry must become invisible, if the parent is set to 'n' - the child entry must become invisible, if the parent is set to 'n'
- the child entry must only be visible, if the parent is visible - the child entry must only be visible, if the parent is visible::
config MODULES config MODULES
bool "Enable loadable module support" bool "Enable loadable module support"
config MODVERSIONS config MODVERSIONS
bool "Set version information on all module symbols" bool "Set version information on all module symbols"
depends on MODULES depends on MODULES
comment "module support disabled" comment "module support disabled"
depends on !MODULES depends on !MODULES
MODVERSIONS directly depends on MODULES, this means it's only visible if MODVERSIONS directly depends on MODULES, this means it's only visible if
...@@ -299,6 +313,7 @@ Kconfig syntax ...@@ -299,6 +313,7 @@ Kconfig syntax
The configuration file describes a series of menu entries, where every The configuration file describes a series of menu entries, where every
line starts with a keyword (except help texts). The following keywords line starts with a keyword (except help texts). The following keywords
end a menu entry: end a menu entry:
- config - config
- menuconfig - menuconfig
- choice/endchoice - choice/endchoice
...@@ -306,17 +321,17 @@ end a menu entry: ...@@ -306,17 +321,17 @@ end a menu entry:
- menu/endmenu - menu/endmenu
- if/endif - if/endif
- source - source
The first five also start the definition of a menu entry.
config: The first five also start the definition of a menu entry.
config::
"config" <symbol> "config" <symbol>
<config options> <config options>
This defines a config symbol <symbol> and accepts any of above This defines a config symbol <symbol> and accepts any of above
attributes as options. attributes as options.
menuconfig: menuconfig::
"menuconfig" <symbol> "menuconfig" <symbol>
<config options> <config options>
...@@ -325,43 +340,43 @@ hint to front ends, that all suboptions should be displayed as a ...@@ -325,43 +340,43 @@ hint to front ends, that all suboptions should be displayed as a
separate list of options. To make sure all the suboptions will really separate list of options. To make sure all the suboptions will really
show up under the menuconfig entry and not outside of it, every item show up under the menuconfig entry and not outside of it, every item
from the <config options> list must depend on the menuconfig symbol. from the <config options> list must depend on the menuconfig symbol.
In practice, this is achieved by using one of the next two constructs: In practice, this is achieved by using one of the next two constructs::
(1): (1):
menuconfig M menuconfig M
if M if M
config C1 config C1
config C2 config C2
endif endif
(2): (2):
menuconfig M menuconfig M
config C1 config C1
depends on M depends on M
config C2 config C2
depends on M depends on M
In the following examples (3) and (4), C1 and C2 still have the M In the following examples (3) and (4), C1 and C2 still have the M
dependency, but will not appear under menuconfig M anymore, because dependency, but will not appear under menuconfig M anymore, because
of C0, which doesn't depend on M: of C0, which doesn't depend on M::
(3): (3):
menuconfig M menuconfig M
config C0 config C0
if M if M
config C1 config C1
config C2 config C2
endif endif
(4): (4):
menuconfig M menuconfig M
config C0 config C0
config C1 config C1
depends on M depends on M
config C2 config C2
depends on M depends on M
choices: choices::
"choice" [symbol] "choice" [symbol]
<choice options> <choice options>
...@@ -387,7 +402,7 @@ definitions of that choice. If a [symbol] is associated to the choice, ...@@ -387,7 +402,7 @@ definitions of that choice. If a [symbol] is associated to the choice,
then you may define the same choice (i.e. with the same entries) in another then you may define the same choice (i.e. with the same entries) in another
place. place.
comment: comment::
"comment" <prompt> "comment" <prompt>
<comment options> <comment options>
...@@ -396,7 +411,7 @@ This defines a comment which is displayed to the user during the ...@@ -396,7 +411,7 @@ This defines a comment which is displayed to the user during the
configuration process and is also echoed to the output files. The only configuration process and is also echoed to the output files. The only
possible options are dependencies. possible options are dependencies.
menu: menu::
"menu" <prompt> "menu" <prompt>
<menu options> <menu options>
...@@ -407,7 +422,7 @@ This defines a menu block, see "Menu structure" above for more ...@@ -407,7 +422,7 @@ This defines a menu block, see "Menu structure" above for more
information. The only possible options are dependencies and "visible" information. The only possible options are dependencies and "visible"
attributes. attributes.
if: if::
"if" <expr> "if" <expr>
<if block> <if block>
...@@ -416,13 +431,13 @@ if: ...@@ -416,13 +431,13 @@ if:
This defines an if block. The dependency expression <expr> is appended This defines an if block. The dependency expression <expr> is appended
to all enclosed menu entries. to all enclosed menu entries.
source: source::
"source" <prompt> "source" <prompt>
This reads the specified configuration file. This file is always parsed. This reads the specified configuration file. This file is always parsed.
mainmenu: mainmenu::
"mainmenu" <prompt> "mainmenu" <prompt>
...@@ -452,20 +467,21 @@ that is defined in a common Kconfig file and selected by the relevant ...@@ -452,20 +467,21 @@ that is defined in a common Kconfig file and selected by the relevant
architectures. architectures.
An example is the generic IOMAP functionality. An example is the generic IOMAP functionality.
We would in lib/Kconfig see: We would in lib/Kconfig see::
# Generic IOMAP is used to ... # Generic IOMAP is used to ...
config HAVE_GENERIC_IOMAP config HAVE_GENERIC_IOMAP
config GENERIC_IOMAP config GENERIC_IOMAP
depends on HAVE_GENERIC_IOMAP && FOO depends on HAVE_GENERIC_IOMAP && FOO
And in lib/Makefile we would see: And in lib/Makefile we would see::
obj-$(CONFIG_GENERIC_IOMAP) += iomap.o
obj-$(CONFIG_GENERIC_IOMAP) += iomap.o
For each architecture using the generic IOMAP functionality we would see: For each architecture using the generic IOMAP functionality we would see::
config X86 config X86
select ... select ...
select HAVE_GENERIC_IOMAP select HAVE_GENERIC_IOMAP
select ... select ...
...@@ -484,25 +500,25 @@ Adding features that need compiler support ...@@ -484,25 +500,25 @@ Adding features that need compiler support
There are several features that need compiler support. The recommended way There are several features that need compiler support. The recommended way
to describe the dependency on the compiler feature is to use "depends on" to describe the dependency on the compiler feature is to use "depends on"
followed by a test macro. followed by a test macro::
config STACKPROTECTOR config STACKPROTECTOR
bool "Stack Protector buffer overflow detection" bool "Stack Protector buffer overflow detection"
depends on $(cc-option,-fstack-protector) depends on $(cc-option,-fstack-protector)
... ...
If you need to expose a compiler capability to makefiles and/or C source files, If you need to expose a compiler capability to makefiles and/or C source files,
CC_HAS_ is the recommended prefix for the config option. `CC_HAS_` is the recommended prefix for the config option::
config CC_HAS_STACKPROTECTOR_NONE config CC_HAS_STACKPROTECTOR_NONE
def_bool $(cc-option,-fno-stack-protector) def_bool $(cc-option,-fno-stack-protector)
Build as module only Build as module only
~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~
To restrict a component build to module-only, qualify its config symbol To restrict a component build to module-only, qualify its config symbol
with "depends on m". E.g.: with "depends on m". E.g.::
config FOO config FOO
depends on BAR && m depends on BAR && m
limits FOO to module (=m) or disabled (=n). limits FOO to module (=m) or disabled (=n).
...@@ -529,18 +545,18 @@ Simple Kconfig recursive issue ...@@ -529,18 +545,18 @@ Simple Kconfig recursive issue
Read: Documentation/kbuild/Kconfig.recursion-issue-01 Read: Documentation/kbuild/Kconfig.recursion-issue-01
Test with: Test with::
make KBUILD_KCONFIG=Documentation/kbuild/Kconfig.recursion-issue-01 allnoconfig make KBUILD_KCONFIG=Documentation/kbuild/Kconfig.recursion-issue-01 allnoconfig
Cumulative Kconfig recursive issue Cumulative Kconfig recursive issue
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Read: Documentation/kbuild/Kconfig.recursion-issue-02 Read: Documentation/kbuild/Kconfig.recursion-issue-02
Test with: Test with::
make KBUILD_KCONFIG=Documentation/kbuild/Kconfig.recursion-issue-02 allnoconfig make KBUILD_KCONFIG=Documentation/kbuild/Kconfig.recursion-issue-02 allnoconfig
Practical solutions to kconfig recursive issue Practical solutions to kconfig recursive issue
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
...@@ -551,7 +567,9 @@ historical issues resolved through these different solutions. ...@@ -551,7 +567,9 @@ historical issues resolved through these different solutions.
a) Remove any superfluous "select FOO" or "depends on FOO" a) Remove any superfluous "select FOO" or "depends on FOO"
b) Match dependency semantics: b) Match dependency semantics:
b1) Swap all "select FOO" to "depends on FOO" or, b1) Swap all "select FOO" to "depends on FOO" or,
b2) Swap all "depends on FOO" to "select FOO" b2) Swap all "depends on FOO" to "select FOO"
The resolution to a) can be tested with the sample Kconfig file The resolution to a) can be tested with the sample Kconfig file
...@@ -566,8 +584,9 @@ Documentation/kbuild/Kconfig.recursion-issue-02. ...@@ -566,8 +584,9 @@ Documentation/kbuild/Kconfig.recursion-issue-02.
Below is a list of examples of prior fixes for these types of recursive issues; Below is a list of examples of prior fixes for these types of recursive issues;
all errors appear to involve one or more select's and one or more "depends on". all errors appear to involve one or more select's and one or more "depends on".
============ ===================================
commit fix commit fix
====== === ============ ===================================
06b718c01208 select A -> depends on A 06b718c01208 select A -> depends on A
c22eacfe82f9 depends on A -> depends on B c22eacfe82f9 depends on A -> depends on B
6a91e854442c select A -> depends on A 6a91e854442c select A -> depends on A
...@@ -590,6 +609,7 @@ d9f9ab51e55e select A -> depends on A ...@@ -590,6 +609,7 @@ d9f9ab51e55e select A -> depends on A
0c51a4d8abd6 depends on A -> select A (3) 0c51a4d8abd6 depends on A -> select A (3)
e98062ed6dc4 select A -> depends on A (3) e98062ed6dc4 select A -> depends on A (3)
91e5d284a7f1 select A -> (null) 91e5d284a7f1 select A -> (null)
============ ===================================
(1) Partial (or no) quote of error. (1) Partial (or no) quote of error.
(2) That seems to be the gist of that fix. (2) That seems to be the gist of that fix.
...@@ -616,11 +636,11 @@ Semantics of Kconfig ...@@ -616,11 +636,11 @@ Semantics of Kconfig
~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~
The use of Kconfig is broad, Linux is now only one of Kconfig's users: The use of Kconfig is broad, Linux is now only one of Kconfig's users:
one study has completed a broad analysis of Kconfig use in 12 projects [0]. one study has completed a broad analysis of Kconfig use in 12 projects [0]_.
Despite its widespread use, and although this document does a reasonable job Despite its widespread use, and although this document does a reasonable job
in documenting basic Kconfig syntax a more precise definition of Kconfig in documenting basic Kconfig syntax a more precise definition of Kconfig
semantics is welcomed. One project deduced Kconfig semantics through semantics is welcomed. One project deduced Kconfig semantics through
the use of the xconfig configurator [1]. Work should be done to confirm if the use of the xconfig configurator [1]_. Work should be done to confirm if
the deduced semantics matches our intended Kconfig design goals. the deduced semantics matches our intended Kconfig design goals.
Having well defined semantics can be useful for tools for practical Having well defined semantics can be useful for tools for practical
...@@ -628,42 +648,42 @@ evaluation of depenencies, for instance one such use known case was work to ...@@ -628,42 +648,42 @@ evaluation of depenencies, for instance one such use known case was work to
express in boolean abstraction of the inferred semantics of Kconfig to express in boolean abstraction of the inferred semantics of Kconfig to
translate Kconfig logic into boolean formulas and run a SAT solver on this to translate Kconfig logic into boolean formulas and run a SAT solver on this to
find dead code / features (always inactive), 114 dead features were found in find dead code / features (always inactive), 114 dead features were found in
Linux using this methodology [1] (Section 8: Threats to validity). Linux using this methodology [1]_ (Section 8: Threats to validity).
Confirming this could prove useful as Kconfig stands as one of the the leading Confirming this could prove useful as Kconfig stands as one of the the leading
industrial variability modeling languages [1] [2]. Its study would help industrial variability modeling languages [1]_ [2]_. Its study would help
evaluate practical uses of such languages, their use was only theoretical evaluate practical uses of such languages, their use was only theoretical
and real world requirements were not well understood. As it stands though and real world requirements were not well understood. As it stands though
only reverse engineering techniques have been used to deduce semantics from only reverse engineering techniques have been used to deduce semantics from
variability modeling languages such as Kconfig [3]. variability modeling languages such as Kconfig [3]_.
[0] http://www.eng.uwaterloo.ca/~shshe/kconfig_semantics.pdf .. [0] http://www.eng.uwaterloo.ca/~shshe/kconfig_semantics.pdf
[1] http://gsd.uwaterloo.ca/sites/default/files/vm-2013-berger.pdf .. [1] http://gsd.uwaterloo.ca/sites/default/files/vm-2013-berger.pdf
[2] http://gsd.uwaterloo.ca/sites/default/files/ase241-berger_0.pdf .. [2] http://gsd.uwaterloo.ca/sites/default/files/ase241-berger_0.pdf
[3] http://gsd.uwaterloo.ca/sites/default/files/icse2011.pdf .. [3] http://gsd.uwaterloo.ca/sites/default/files/icse2011.pdf
Full SAT solver for Kconfig Full SAT solver for Kconfig
~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~
Although SAT solvers [0] haven't yet been used by Kconfig directly, as noted in Although SAT solvers [4]_ haven't yet been used by Kconfig directly, as noted
the previous subsection, work has been done however to express in boolean in the previous subsection, work has been done however to express in boolean
abstraction the inferred semantics of Kconfig to translate Kconfig logic into abstraction the inferred semantics of Kconfig to translate Kconfig logic into
boolean formulas and run a SAT solver on it [1]. Another known related project boolean formulas and run a SAT solver on it [5]_. Another known related project
is CADOS [2] (former VAMOS [3]) and the tools, mainly undertaker [4], which has is CADOS [6]_ (former VAMOS [7]_) and the tools, mainly undertaker [8]_, which
been introduced first with [5]. The basic concept of undertaker is to exract has been introduced first with [9]_. The basic concept of undertaker is to
variability models from Kconfig, and put them together with a propositional exract variability models from Kconfig, and put them together with a
formula extracted from CPP #ifdefs and build-rules into a SAT solver in order propositional formula extracted from CPP #ifdefs and build-rules into a SAT
to find dead code, dead files, and dead symbols. If using a SAT solver is solver in order to find dead code, dead files, and dead symbols. If using a SAT
desirable on Kconfig one approach would be to evaluate repurposing such efforts solver is desirable on Kconfig one approach would be to evaluate repurposing
somehow on Kconfig. There is enough interest from mentors of existing projects such efforts somehow on Kconfig. There is enough interest from mentors of
to not only help advise how to integrate this work upstream but also help existing projects to not only help advise how to integrate this work upstream
maintain it long term. Interested developers should visit: but also help maintain it long term. Interested developers should visit:
http://kernelnewbies.org/KernelProjects/kconfig-sat http://kernelnewbies.org/KernelProjects/kconfig-sat
[0] http://www.cs.cornell.edu/~sabhar/chapters/SATSolvers-KR-Handbook.pdf .. [4] http://www.cs.cornell.edu/~sabhar/chapters/SATSolvers-KR-Handbook.pdf
[1] http://gsd.uwaterloo.ca/sites/default/files/vm-2013-berger.pdf .. [5] http://gsd.uwaterloo.ca/sites/default/files/vm-2013-berger.pdf
[2] https://cados.cs.fau.de .. [6] https://cados.cs.fau.de
[3] https://vamos.cs.fau.de .. [7] https://vamos.cs.fau.de
[4] https://undertaker.cs.fau.de .. [8] https://undertaker.cs.fau.de
[5] https://www4.cs.fau.de/Publications/2011/tartler_11_eurosys.pdf .. [9] https://www4.cs.fau.de/Publications/2011/tartler_11_eurosys.pdf
Documentation/kbuild/kconfig-macro-language.txt → Documentation/kbuild/kconfig-macro-language.rst
View file @ cd238eff
======================
Kconfig macro language
======================
Concept Concept
------- -------
...@@ -7,7 +11,7 @@ targets and prerequisites. The other is a macro language for performing textual ...@@ -7,7 +11,7 @@ targets and prerequisites. The other is a macro language for performing textual
substitution. substitution.
There is clear distinction between the two language stages. For example, you There is clear distinction between the two language stages. For example, you
can write a makefile like follows: can write a makefile like follows::
APP := foo APP := foo
SRC := foo.c SRC := foo.c
...@@ -17,7 +21,7 @@ can write a makefile like follows: ...@@ -17,7 +21,7 @@ can write a makefile like follows:
$(CC) -o $(APP) $(SRC) $(CC) -o $(APP) $(SRC)
The macro language replaces the variable references with their expanded form, The macro language replaces the variable references with their expanded form,
and handles as if the source file were input like follows: and handles as if the source file were input like follows::
foo: foo.c foo: foo.c
gcc -o foo foo.c gcc -o foo foo.c
...@@ -26,7 +30,7 @@ Then, Make analyzes the dependency graph and determines the targets to be ...@@ -26,7 +30,7 @@ Then, Make analyzes the dependency graph and determines the targets to be
updated. updated.
The idea is quite similar in Kconfig - it is possible to describe a Kconfig The idea is quite similar in Kconfig - it is possible to describe a Kconfig
file like this: file like this::
CC := gcc CC := gcc
...@@ -34,7 +38,7 @@ file like this: ...@@ -34,7 +38,7 @@ file like this:
def_bool $(shell, $(srctree)/scripts/gcc-check-foo.sh $(CC)) def_bool $(shell, $(srctree)/scripts/gcc-check-foo.sh $(CC))
The macro language in Kconfig processes the source file into the following The macro language in Kconfig processes the source file into the following
intermediate: intermediate::
config CC_HAS_FOO config CC_HAS_FOO
def_bool y def_bool y
...@@ -69,7 +73,7 @@ variable. The righthand side of += is expanded immediately if the lefthand ...@@ -69,7 +73,7 @@ variable. The righthand side of += is expanded immediately if the lefthand
side was originally defined as a simple variable. Otherwise, its evaluation is side was originally defined as a simple variable. Otherwise, its evaluation is
deferred. deferred.
The variable reference can take parameters, in the following form: The variable reference can take parameters, in the following form::
$(name,arg1,arg2,arg3) $(name,arg1,arg2,arg3)
...@@ -141,7 +145,7 @@ Make vs Kconfig ...@@ -141,7 +145,7 @@ Make vs Kconfig
Kconfig adopts Make-like macro language, but the function call syntax is Kconfig adopts Make-like macro language, but the function call syntax is
slightly different. slightly different.
A function call in Make looks like this: A function call in Make looks like this::
$(func-name arg1,arg2,arg3) $(func-name arg1,arg2,arg3)
...@@ -149,14 +153,14 @@ The function name and the first argument are separated by at least one ...@@ -149,14 +153,14 @@ The function name and the first argument are separated by at least one
whitespace. Then, leading whitespaces are trimmed from the first argument, whitespace. Then, leading whitespaces are trimmed from the first argument,
while whitespaces in the other arguments are kept. You need to use a kind of while whitespaces in the other arguments are kept. You need to use a kind of
trick to start the first parameter with spaces. For example, if you want trick to start the first parameter with spaces. For example, if you want
to make "info" function print " hello", you can write like follows: to make "info" function print " hello", you can write like follows::
empty := empty :=
space := $(empty) $(empty) space := $(empty) $(empty)
$(info $(space)$(space)hello) $(info $(space)$(space)hello)
Kconfig uses only commas for delimiters, and keeps all whitespaces in the Kconfig uses only commas for delimiters, and keeps all whitespaces in the
function call. Some people prefer putting a space after each comma delimiter: function call. Some people prefer putting a space after each comma delimiter::
$(func-name, arg1, arg2, arg3) $(func-name, arg1, arg2, arg3)
...@@ -166,7 +170,7 @@ Make - for example, $(subst .c, .o, $(sources)) is a typical mistake; it ...@@ -166,7 +170,7 @@ Make - for example, $(subst .c, .o, $(sources)) is a typical mistake; it
replaces ".c" with " .o". replaces ".c" with " .o".
In Make, a user-defined function is referenced by using a built-in function, In Make, a user-defined function is referenced by using a built-in function,
'call', like this: 'call', like this::
$(call my-func,arg1,arg2,arg3) $(call my-func,arg1,arg2,arg3)
...@@ -179,12 +183,12 @@ Likewise, $(info hello, world) prints "hello, world" to stdout. You could say ...@@ -179,12 +183,12 @@ Likewise, $(info hello, world) prints "hello, world" to stdout. You could say
this is _useful_ inconsistency. this is _useful_ inconsistency.
In Kconfig, for simpler implementation and grammatical consistency, commas that In Kconfig, for simpler implementation and grammatical consistency, commas that
appear in the $( ) context are always delimiters. It means appear in the $( ) context are always delimiters. It means::
$(shell, echo hello, world) $(shell, echo hello, world)
is an error because it is passing two parameters where the 'shell' function is an error because it is passing two parameters where the 'shell' function
accepts only one. To pass commas in arguments, you can use the following trick: accepts only one. To pass commas in arguments, you can use the following trick::
comma := , comma := ,
$(shell, echo hello$(comma) world) $(shell, echo hello$(comma) world)
...@@ -195,7 +199,7 @@ Caveats ...@@ -195,7 +199,7 @@ Caveats
A variable (or function) cannot be expanded across tokens. So, you cannot use A variable (or function) cannot be expanded across tokens. So, you cannot use
a variable as a shorthand for an expression that consists of multiple tokens. a variable as a shorthand for an expression that consists of multiple tokens.
The following works: The following works::
RANGE_MIN := 1 RANGE_MIN := 1
RANGE_MAX := 3 RANGE_MAX := 3
...@@ -204,7 +208,7 @@ The following works: ...@@ -204,7 +208,7 @@ The following works:
int "foo" int "foo"
range $(RANGE_MIN) $(RANGE_MAX) range $(RANGE_MIN) $(RANGE_MAX)
But, the following does not work: But, the following does not work::
RANGES := 1 3 RANGES := 1 3
...@@ -213,7 +217,7 @@ But, the following does not work: ...@@ -213,7 +217,7 @@ But, the following does not work:
range $(RANGES) range $(RANGES)
A variable cannot be expanded to any keyword in Kconfig. The following does A variable cannot be expanded to any keyword in Kconfig. The following does
not work: not work::
MY_TYPE := tristate MY_TYPE := tristate
...@@ -223,7 +227,8 @@ not work: ...@@ -223,7 +227,8 @@ not work:
Obviously from the design, $(shell command) is expanded in the textual Obviously from the design, $(shell command) is expanded in the textual
substitution phase. You cannot pass symbols to the 'shell' function. substitution phase. You cannot pass symbols to the 'shell' function.
The following does not work as expected.
The following does not work as expected::
config ENDIAN_FLAG config ENDIAN_FLAG
string string
...@@ -234,7 +239,7 @@ The following does not work as expected. ...@@ -234,7 +239,7 @@ The following does not work as expected.
def_bool $(shell $(srctree)/scripts/gcc-check-flag ENDIAN_FLAG) def_bool $(shell $(srctree)/scripts/gcc-check-flag ENDIAN_FLAG)
Instead, you can do like follows so that any function call is statically Instead, you can do like follows so that any function call is statically
expanded. expanded::
config CC_HAS_ENDIAN_FLAG config CC_HAS_ENDIAN_FLAG
bool bool
......
Documentation/kbuild/kconfig.txt → Documentation/kbuild/kconfig.rst
View file @ cd238eff
This file contains some assistance for using "make *config". ===================
Kconfig make config
===================
This file contains some assistance for using `make *config`.
Use "make help" to list all of the possible configuration targets. Use "make help" to list all of the possible configuration targets.
...@@ -6,9 +10,8 @@ The xconfig ('qconf'), menuconfig ('mconf'), and nconfig ('nconf') ...@@ -6,9 +10,8 @@ The xconfig ('qconf'), menuconfig ('mconf'), and nconfig ('nconf')
programs also have embedded help text. Be sure to check that for programs also have embedded help text. Be sure to check that for
navigation, search, and other general help text. navigation, search, and other general help text.
======================================================================
General General
-------------------------------------------------- -------
New kernel releases often introduce new config symbols. Often more New kernel releases often introduce new config symbols. Often more
important, new kernel releases may rename config symbols. When important, new kernel releases may rename config symbols. When
...@@ -17,51 +20,55 @@ this happens, using a previously working .config file and running ...@@ -17,51 +20,55 @@ this happens, using a previously working .config file and running
for you, so you may find that you need to see what NEW kernel for you, so you may find that you need to see what NEW kernel
symbols have been introduced. symbols have been introduced.
To see a list of new config symbols, use To see a list of new config symbols, use::
cp user/some/old.config .config cp user/some/old.config .config
make listnewconfig make listnewconfig
and the config program will list any new symbols, one per line. and the config program will list any new symbols, one per line.
Alternatively, you can use the brute force method: Alternatively, you can use the brute force method::
make oldconfig make oldconfig
scripts/diffconfig .config.old .config | less scripts/diffconfig .config.old .config | less
______________________________________________________________________ ----------------------------------------------------------------------
Environment variables for '*config'
Environment variables for `*config`
KCONFIG_CONFIG KCONFIG_CONFIG
-------------------------------------------------- --------------
This environment variable can be used to specify a default kernel config This environment variable can be used to specify a default kernel config
file name to override the default name of ".config". file name to override the default name of ".config".
KCONFIG_OVERWRITECONFIG KCONFIG_OVERWRITECONFIG
-------------------------------------------------- -----------------------
If you set KCONFIG_OVERWRITECONFIG in the environment, Kconfig will not If you set KCONFIG_OVERWRITECONFIG in the environment, Kconfig will not
break symlinks when .config is a symlink to somewhere else. break symlinks when .config is a symlink to somewhere else.
CONFIG_ `CONFIG_`
-------------------------------------------------- ---------
If you set CONFIG_ in the environment, Kconfig will prefix all symbols If you set `CONFIG_` in the environment, Kconfig will prefix all symbols
with its value when saving the configuration, instead of using the default, with its value when saving the configuration, instead of using the default,
"CONFIG_". `CONFIG_`.
----------------------------------------------------------------------
______________________________________________________________________
Environment variables for '{allyes/allmod/allno/rand}config' Environment variables for '{allyes/allmod/allno/rand}config'
KCONFIG_ALLCONFIG KCONFIG_ALLCONFIG
-------------------------------------------------- -----------------
(partially based on lkml email from/by Rob Landley, re: miniconfig) (partially based on lkml email from/by Rob Landley, re: miniconfig)
-------------------------------------------------- --------------------------------------------------
The allyesconfig/allmodconfig/allnoconfig/randconfig variants can also The allyesconfig/allmodconfig/allnoconfig/randconfig variants can also
use the environment variable KCONFIG_ALLCONFIG as a flag or a filename use the environment variable KCONFIG_ALLCONFIG as a flag or a filename
that contains config symbols that the user requires to be set to a that contains config symbols that the user requires to be set to a
specific value. If KCONFIG_ALLCONFIG is used without a filename where specific value. If KCONFIG_ALLCONFIG is used without a filename where
KCONFIG_ALLCONFIG == "" or KCONFIG_ALLCONFIG == "1", "make *config" KCONFIG_ALLCONFIG == "" or KCONFIG_ALLCONFIG == "1", `make *config`
checks for a file named "all{yes/mod/no/def/random}.config" checks for a file named "all{yes/mod/no/def/random}.config"
(corresponding to the *config command that was used) for symbol values (corresponding to the `*config` command that was used) for symbol values
that are to be forced. If this file is not found, it checks for a that are to be forced. If this file is not found, it checks for a
file named "all.config" to contain forced values. file named "all.config" to contain forced values.
...@@ -74,43 +81,55 @@ This 'KCONFIG_ALLCONFIG' file is a config file which contains ...@@ -74,43 +81,55 @@ This 'KCONFIG_ALLCONFIG' file is a config file which contains
(usually a subset of all) preset config symbols. These variable (usually a subset of all) preset config symbols. These variable
settings are still subject to normal dependency checks. settings are still subject to normal dependency checks.
Examples: Examples::
KCONFIG_ALLCONFIG=custom-notebook.config make allnoconfig KCONFIG_ALLCONFIG=custom-notebook.config make allnoconfig
or
or::
KCONFIG_ALLCONFIG=mini.config make allnoconfig KCONFIG_ALLCONFIG=mini.config make allnoconfig
or
or::
make KCONFIG_ALLCONFIG=mini.config allnoconfig make KCONFIG_ALLCONFIG=mini.config allnoconfig
These examples will disable most options (allnoconfig) but enable or These examples will disable most options (allnoconfig) but enable or
disable the options that are explicitly listed in the specified disable the options that are explicitly listed in the specified
mini-config files. mini-config files.
______________________________________________________________________ ----------------------------------------------------------------------
Environment variables for 'randconfig' Environment variables for 'randconfig'
KCONFIG_SEED KCONFIG_SEED
-------------------------------------------------- ------------
You can set this to the integer value used to seed the RNG, if you want You can set this to the integer value used to seed the RNG, if you want
to somehow debug the behaviour of the kconfig parser/frontends. to somehow debug the behaviour of the kconfig parser/frontends.
If not set, the current time will be used. If not set, the current time will be used.
KCONFIG_PROBABILITY KCONFIG_PROBABILITY
-------------------------------------------------- -------------------
This variable can be used to skew the probabilities. This variable can This variable can be used to skew the probabilities. This variable can
be unset or empty, or set to three different formats: be unset or empty, or set to three different formats:
======================= ================== =====================
KCONFIG_PROBABILITY y:n split y:m:n split KCONFIG_PROBABILITY y:n split y:m:n split
----------------------------------------------------------------- ======================= ================== =====================
unset or empty 50 : 50 33 : 33 : 34 unset or empty 50 : 50 33 : 33 : 34
N N : 100-N N/2 : N/2 : 100-N N N : 100-N N/2 : N/2 : 100-N
[1] N:M N+M : 100-(N+M) N : M : 100-(N+M) [1] N:M N+M : 100-(N+M) N : M : 100-(N+M)
[2] N:M:L N : 100-N M : L : 100-(M+L) [2] N:M:L N : 100-N M : L : 100-(M+L)
======================= ================== =====================
where N, M and L are integers (in base 10) in the range [0,100], and so where N, M and L are integers (in base 10) in the range [0,100], and so
that: that:
[1] N+M is in the range [0,100] [1] N+M is in the range [0,100]
[2] M+L is in the range [0,100] [2] M+L is in the range [0,100]
Examples: Examples::
KCONFIG_PROBABILITY=10 KCONFIG_PROBABILITY=10
10% of booleans will be set to 'y', 90% to 'n' 10% of booleans will be set to 'y', 90% to 'n'
5% of tristates will be set to 'y', 5% to 'm', 90% to 'n' 5% of tristates will be set to 'y', 5% to 'm', 90% to 'n'
...@@ -121,34 +140,36 @@ Examples: ...@@ -121,34 +140,36 @@ Examples:
10% of booleans will be set to 'y', 90% to 'n' 10% of booleans will be set to 'y', 90% to 'n'
15% of tristates will be set to 'y', 15% to 'm', 70% to 'n' 15% of tristates will be set to 'y', 15% to 'm', 70% to 'n'
______________________________________________________________________ ----------------------------------------------------------------------
Environment variables for 'syncconfig' Environment variables for 'syncconfig'
KCONFIG_NOSILENTUPDATE KCONFIG_NOSILENTUPDATE
-------------------------------------------------- ----------------------
If this variable has a non-blank value, it prevents silent kernel If this variable has a non-blank value, it prevents silent kernel
config updates (requires explicit updates). config updates (requires explicit updates).
KCONFIG_AUTOCONFIG KCONFIG_AUTOCONFIG
-------------------------------------------------- ------------------
This environment variable can be set to specify the path & name of the This environment variable can be set to specify the path & name of the
"auto.conf" file. Its default value is "include/config/auto.conf". "auto.conf" file. Its default value is "include/config/auto.conf".
KCONFIG_TRISTATE KCONFIG_TRISTATE
-------------------------------------------------- ----------------
This environment variable can be set to specify the path & name of the This environment variable can be set to specify the path & name of the
"tristate.conf" file. Its default value is "include/config/tristate.conf". "tristate.conf" file. Its default value is "include/config/tristate.conf".
KCONFIG_AUTOHEADER KCONFIG_AUTOHEADER
-------------------------------------------------- ------------------
This environment variable can be set to specify the path & name of the This environment variable can be set to specify the path & name of the
"autoconf.h" (header) file. "autoconf.h" (header) file.
Its default value is "include/generated/autoconf.h". Its default value is "include/generated/autoconf.h".
====================================================================== ----------------------------------------------------------------------
menuconfig menuconfig
-------------------------------------------------- ----------
SEARCHING for CONFIG symbols SEARCHING for CONFIG symbols
...@@ -158,7 +179,8 @@ Searching in menuconfig: ...@@ -158,7 +179,8 @@ Searching in menuconfig:
names, so you have to know something close to what you are names, so you have to know something close to what you are
looking for. looking for.
Example: Example::
/hotplug /hotplug
This lists all config symbols that contain "hotplug", This lists all config symbols that contain "hotplug",
e.g., HOTPLUG_CPU, MEMORY_HOTPLUG. e.g., HOTPLUG_CPU, MEMORY_HOTPLUG.
...@@ -166,48 +188,55 @@ Searching in menuconfig: ...@@ -166,48 +188,55 @@ Searching in menuconfig:
For search help, enter / followed by TAB-TAB (to highlight For search help, enter / followed by TAB-TAB (to highlight
<Help>) and Enter. This will tell you that you can also use <Help>) and Enter. This will tell you that you can also use
regular expressions (regexes) in the search string, so if you regular expressions (regexes) in the search string, so if you
are not interested in MEMORY_HOTPLUG, you could try are not interested in MEMORY_HOTPLUG, you could try::
/^hotplug /^hotplug
When searching, symbols are sorted thus: When searching, symbols are sorted thus:
- first, exact matches, sorted alphabetically (an exact match - first, exact matches, sorted alphabetically (an exact match
is when the search matches the complete symbol name); is when the search matches the complete symbol name);
- then, other matches, sorted alphabetically. - then, other matches, sorted alphabetically.
For example: ^ATH.K matches: For example: ^ATH.K matches:
ATH5K ATH9K ATH5K_AHB ATH5K_DEBUG [...] ATH6KL ATH6KL_DEBUG ATH5K ATH9K ATH5K_AHB ATH5K_DEBUG [...] ATH6KL ATH6KL_DEBUG
[...] ATH9K_AHB ATH9K_BTCOEX_SUPPORT ATH9K_COMMON [...] [...] ATH9K_AHB ATH9K_BTCOEX_SUPPORT ATH9K_COMMON [...]
of which only ATH5K and ATH9K match exactly and so are sorted of which only ATH5K and ATH9K match exactly and so are sorted
first (and in alphabetical order), then come all other symbols, first (and in alphabetical order), then come all other symbols,
sorted in alphabetical order. sorted in alphabetical order.
______________________________________________________________________ ----------------------------------------------------------------------
User interface options for 'menuconfig' User interface options for 'menuconfig'
MENUCONFIG_COLOR MENUCONFIG_COLOR
-------------------------------------------------- ----------------
It is possible to select different color themes using the variable It is possible to select different color themes using the variable
MENUCONFIG_COLOR. To select a theme use: MENUCONFIG_COLOR. To select a theme use::
make MENUCONFIG_COLOR=<theme> menuconfig make MENUCONFIG_COLOR=<theme> menuconfig
Available themes are: Available themes are::
mono => selects colors suitable for monochrome displays
blackbg => selects a color scheme with black background - mono => selects colors suitable for monochrome displays
classic => theme with blue background. The classic look - blackbg => selects a color scheme with black background
bluetitle => a LCD friendly version of classic. (default) - classic => theme with blue background. The classic look
- bluetitle => a LCD friendly version of classic. (default)
MENUCONFIG_MODE MENUCONFIG_MODE
-------------------------------------------------- ---------------
This mode shows all sub-menus in one large tree. This mode shows all sub-menus in one large tree.
Example: Example::
make MENUCONFIG_MODE=single_menu menuconfig make MENUCONFIG_MODE=single_menu menuconfig
----------------------------------------------------------------------
======================================================================
nconfig nconfig
-------------------------------------------------- -------
nconfig is an alternate text-based configurator. It lists function nconfig is an alternate text-based configurator. It lists function
keys across the bottom of the terminal (window) that execute commands. keys across the bottom of the terminal (window) that execute commands.
...@@ -231,16 +260,16 @@ Searching in nconfig: ...@@ -231,16 +260,16 @@ Searching in nconfig:
given string or regular expression (regex). given string or regular expression (regex).
NCONFIG_MODE NCONFIG_MODE
-------------------------------------------------- ------------
This mode shows all sub-menus in one large tree. This mode shows all sub-menus in one large tree.
Example: Example::
make NCONFIG_MODE=single_menu nconfig make NCONFIG_MODE=single_menu nconfig
----------------------------------------------------------------------
======================================================================
xconfig xconfig
-------------------------------------------------- -------
Searching in xconfig: Searching in xconfig:
...@@ -260,13 +289,12 @@ Searching in xconfig: ...@@ -260,13 +289,12 @@ Searching in xconfig:
to return to the main menu. to return to the main menu.
====================================================================== ----------------------------------------------------------------------
gconfig gconfig
-------------------------------------------------- -------
Searching in gconfig: Searching in gconfig:
There is no search command in gconfig. However, gconfig does There is no search command in gconfig. However, gconfig does
have several different viewing choices, modes, and options. have several different viewing choices, modes, and options.
###
Documentation/kbuild/makefiles.txt → Documentation/kbuild/makefiles.rst
View file @ cd238eff
======================
Linux Kernel Makefiles Linux Kernel Makefiles
======================
This document describes the Linux kernel Makefiles. This document describes the Linux kernel Makefiles.
=== Table of Contents .. Table of Contents
=== 1 Overview === 1 Overview
=== 2 Who does what === 2 Who does what
...@@ -54,9 +56,10 @@ This document describes the Linux kernel Makefiles. ...@@ -54,9 +56,10 @@ This document describes the Linux kernel Makefiles.
=== 10 Credits === 10 Credits
=== 11 TODO === 11 TODO
=== 1 Overview 1 Overview
==========
The Makefiles have five parts: The Makefiles have five parts::
Makefile the top Makefile. Makefile the top Makefile.
.config the kernel configuration file. .config the kernel configuration file.
...@@ -85,7 +88,8 @@ scripts/Makefile.* contains all the definitions/rules etc. that ...@@ -85,7 +88,8 @@ scripts/Makefile.* contains all the definitions/rules etc. that
are used to build the kernel based on the kbuild makefiles. are used to build the kernel based on the kbuild makefiles.
=== 2 Who does what 2 Who does what
===============
People have four different relationships with the kernel Makefiles. People have four different relationships with the kernel Makefiles.
...@@ -110,7 +114,8 @@ These people need to know about all aspects of the kernel Makefiles. ...@@ -110,7 +114,8 @@ These people need to know about all aspects of the kernel Makefiles.
This document is aimed towards normal developers and arch developers. This document is aimed towards normal developers and arch developers.
=== 3 The kbuild files 3 The kbuild files
==================
Most Makefiles within the kernel are kbuild Makefiles that use the Most Makefiles within the kernel are kbuild Makefiles that use the
kbuild infrastructure. This chapter introduces the syntax used in the kbuild infrastructure. This chapter introduces the syntax used in the
...@@ -122,7 +127,8 @@ file will be used. ...@@ -122,7 +127,8 @@ file will be used.
Section 3.1 "Goal definitions" is a quick intro, further chapters provide Section 3.1 "Goal definitions" is a quick intro, further chapters provide
more details, with real examples. more details, with real examples.
--- 3.1 Goal definitions 3.1 Goal definitions
--------------------
Goal definitions are the main part (heart) of the kbuild Makefile. Goal definitions are the main part (heart) of the kbuild Makefile.
These lines define the files to be built, any special compilation These lines define the files to be built, any special compilation
...@@ -130,7 +136,8 @@ more details, with real examples. ...@@ -130,7 +136,8 @@ more details, with real examples.
The most simple kbuild makefile contains one line: The most simple kbuild makefile contains one line:
Example: Example::
obj-y += foo.o obj-y += foo.o
This tells kbuild that there is one object in that directory, named This tells kbuild that there is one object in that directory, named
...@@ -139,14 +146,16 @@ more details, with real examples. ...@@ -139,14 +146,16 @@ more details, with real examples.
If foo.o shall be built as a module, the variable obj-m is used. If foo.o shall be built as a module, the variable obj-m is used.
Therefore the following pattern is often used: Therefore the following pattern is often used:
Example: Example::
obj-$(CONFIG_FOO) += foo.o obj-$(CONFIG_FOO) += foo.o
$(CONFIG_FOO) evaluates to either y (for built-in) or m (for module). $(CONFIG_FOO) evaluates to either y (for built-in) or m (for module).
If CONFIG_FOO is neither y nor m, then the file will not be compiled If CONFIG_FOO is neither y nor m, then the file will not be compiled
nor linked. nor linked.
--- 3.2 Built-in object goals - obj-y 3.2 Built-in object goals - obj-y
---------------------------------
The kbuild Makefile specifies object files for vmlinux The kbuild Makefile specifies object files for vmlinux
in the $(obj-y) lists. These lists depend on the kernel in the $(obj-y) lists. These lists depend on the kernel
...@@ -167,14 +176,16 @@ more details, with real examples. ...@@ -167,14 +176,16 @@ more details, with real examples.
order may e.g. change the order in which your SCSI order may e.g. change the order in which your SCSI
controllers are detected, and thus your disks are renumbered. controllers are detected, and thus your disks are renumbered.
Example: Example::
#drivers/isdn/i4l/Makefile #drivers/isdn/i4l/Makefile
# Makefile for the kernel ISDN subsystem and device drivers. # Makefile for the kernel ISDN subsystem and device drivers.
# Each configuration option enables a list of files. # Each configuration option enables a list of files.
obj-$(CONFIG_ISDN_I4L) += isdn.o obj-$(CONFIG_ISDN_I4L) += isdn.o
obj-$(CONFIG_ISDN_PPP_BSDCOMP) += isdn_bsdcomp.o obj-$(CONFIG_ISDN_PPP_BSDCOMP) += isdn_bsdcomp.o
--- 3.3 Loadable module goals - obj-m 3.3 Loadable module goals - obj-m
---------------------------------
$(obj-m) specifies object files which are built as loadable $(obj-m) specifies object files which are built as loadable
kernel modules. kernel modules.
...@@ -183,7 +194,8 @@ more details, with real examples. ...@@ -183,7 +194,8 @@ more details, with real examples.
files. In the case of one source file, the kbuild makefile files. In the case of one source file, the kbuild makefile
simply adds the file to $(obj-m). simply adds the file to $(obj-m).
Example: Example::
#drivers/isdn/i4l/Makefile #drivers/isdn/i4l/Makefile
obj-$(CONFIG_ISDN_PPP_BSDCOMP) += isdn_bsdcomp.o obj-$(CONFIG_ISDN_PPP_BSDCOMP) += isdn_bsdcomp.o
...@@ -195,7 +207,8 @@ more details, with real examples. ...@@ -195,7 +207,8 @@ more details, with real examples.
module from, so you have to tell it by setting a $(<module_name>-y) module from, so you have to tell it by setting a $(<module_name>-y)
variable. variable.
Example: Example::
#drivers/isdn/i4l/Makefile #drivers/isdn/i4l/Makefile
obj-$(CONFIG_ISDN_I4L) += isdn.o obj-$(CONFIG_ISDN_I4L) += isdn.o
isdn-y := isdn_net_lib.o isdn_v110.o isdn_common.o isdn-y := isdn_net_lib.o isdn_v110.o isdn_common.o
...@@ -205,10 +218,11 @@ more details, with real examples. ...@@ -205,10 +218,11 @@ more details, with real examples.
"$(LD) -r" on the list of these files to generate isdn.o. "$(LD) -r" on the list of these files to generate isdn.o.
Due to kbuild recognizing $(<module_name>-y) for composite objects, Due to kbuild recognizing $(<module_name>-y) for composite objects,
you can use the value of a CONFIG_ symbol to optionally include an you can use the value of a `CONFIG_` symbol to optionally include an
object file as part of a composite object. object file as part of a composite object.
Example: Example::
#fs/ext2/Makefile #fs/ext2/Makefile
obj-$(CONFIG_EXT2_FS) += ext2.o obj-$(CONFIG_EXT2_FS) += ext2.o
ext2-y := balloc.o dir.o file.o ialloc.o inode.o ioctl.o \ ext2-y := balloc.o dir.o file.o ialloc.o inode.o ioctl.o \
...@@ -225,12 +239,14 @@ more details, with real examples. ...@@ -225,12 +239,14 @@ more details, with real examples.
kbuild will build an ext2.o file for you out of the individual kbuild will build an ext2.o file for you out of the individual
parts and then link this into built-in.a, as you would expect. parts and then link this into built-in.a, as you would expect.
--- 3.4 Objects which export symbols 3.4 Objects which export symbols
--------------------------------
No special notation is required in the makefiles for No special notation is required in the makefiles for
modules exporting symbols. modules exporting symbols.
--- 3.5 Library file goals - lib-y 3.5 Library file goals - lib-y
------------------------------
Objects listed with obj-* are used for modules, or Objects listed with obj-* are used for modules, or
combined in a built-in.a for that specific directory. combined in a built-in.a for that specific directory.
...@@ -247,18 +263,21 @@ more details, with real examples. ...@@ -247,18 +263,21 @@ more details, with real examples.
and to be part of a library. Therefore the same directory and to be part of a library. Therefore the same directory
may contain both a built-in.a and a lib.a file. may contain both a built-in.a and a lib.a file.
Example: Example::
#arch/x86/lib/Makefile #arch/x86/lib/Makefile
lib-y := delay.o lib-y := delay.o
This will create a library lib.a based on delay.o. For kbuild to This will create a library lib.a based on delay.o. For kbuild to
actually recognize that there is a lib.a being built, the directory actually recognize that there is a lib.a being built, the directory
shall be listed in libs-y. shall be listed in libs-y.
See also "6.4 List directories to visit when descending". See also "6.4 List directories to visit when descending".
Use of lib-y is normally restricted to lib/ and arch/*/lib. Use of lib-y is normally restricted to `lib/` and `arch/*/lib`.
--- 3.6 Descending down in directories 3.6 Descending down in directories
----------------------------------
A Makefile is only responsible for building objects in its own A Makefile is only responsible for building objects in its own
directory. Files in subdirectories should be taken care of by directory. Files in subdirectories should be taken care of by
...@@ -270,7 +289,8 @@ more details, with real examples. ...@@ -270,7 +289,8 @@ more details, with real examples.
ext2 lives in a separate directory, and the Makefile present in fs/ ext2 lives in a separate directory, and the Makefile present in fs/
tells kbuild to descend down using the following assignment. tells kbuild to descend down using the following assignment.
Example: Example::
#fs/Makefile #fs/Makefile
obj-$(CONFIG_EXT2_FS) += ext2/ obj-$(CONFIG_EXT2_FS) += ext2/
...@@ -281,11 +301,12 @@ more details, with real examples. ...@@ -281,11 +301,12 @@ more details, with real examples.
the directory, it is the Makefile in the subdirectory that the directory, it is the Makefile in the subdirectory that
specifies what is modular and what is built-in. specifies what is modular and what is built-in.
It is good practice to use a CONFIG_ variable when assigning directory It is good practice to use a `CONFIG_` variable when assigning directory
names. This allows kbuild to totally skip the directory if the names. This allows kbuild to totally skip the directory if the
corresponding CONFIG_ option is neither 'y' nor 'm'. corresponding `CONFIG_` option is neither 'y' nor 'm'.
--- 3.7 Compilation flags 3.7 Compilation flags
---------------------
ccflags-y, asflags-y and ldflags-y ccflags-y, asflags-y and ldflags-y
These three flags apply only to the kbuild makefile in which they These three flags apply only to the kbuild makefile in which they
...@@ -297,7 +318,8 @@ more details, with real examples. ...@@ -297,7 +318,8 @@ more details, with real examples.
ccflags-y specifies options for compiling with $(CC). ccflags-y specifies options for compiling with $(CC).
Example: Example::
# drivers/acpi/acpica/Makefile # drivers/acpi/acpica/Makefile
ccflags-y := -Os -D_LINUX -DBUILDING_ACPICA ccflags-y := -Os -D_LINUX -DBUILDING_ACPICA
ccflags-$(CONFIG_ACPI_DEBUG) += -DACPI_DEBUG_OUTPUT ccflags-$(CONFIG_ACPI_DEBUG) += -DACPI_DEBUG_OUTPUT
...@@ -308,13 +330,15 @@ more details, with real examples. ...@@ -308,13 +330,15 @@ more details, with real examples.
asflags-y specifies options for assembling with $(AS). asflags-y specifies options for assembling with $(AS).
Example: Example::
#arch/sparc/kernel/Makefile #arch/sparc/kernel/Makefile
asflags-y := -ansi asflags-y := -ansi
ldflags-y specifies options for linking with $(LD). ldflags-y specifies options for linking with $(LD).
Example: Example::
#arch/cris/boot/compressed/Makefile #arch/cris/boot/compressed/Makefile
ldflags-y += -T $(srctree)/$(src)/decompress_$(arch-y).lds ldflags-y += -T $(srctree)/$(src)/decompress_$(arch-y).lds
...@@ -325,18 +349,19 @@ more details, with real examples. ...@@ -325,18 +349,19 @@ more details, with real examples.
Options specified using subdir-* are added to the commandline before Options specified using subdir-* are added to the commandline before
the options specified using the non-subdir variants. the options specified using the non-subdir variants.
Example: Example::
subdir-ccflags-y := -Werror subdir-ccflags-y := -Werror
CFLAGS_$@, AFLAGS_$@ CFLAGS_$@, AFLAGS_$@
CFLAGS_$@ and AFLAGS_$@ only apply to commands in current CFLAGS_$@ and AFLAGS_$@ only apply to commands in current
kbuild makefile. kbuild makefile.
$(CFLAGS_$@) specifies per-file options for $(CC). The $@ $(CFLAGS_$@) specifies per-file options for $(CC). The $@
part has a literal value which specifies the file that it is for. part has a literal value which specifies the file that it is for.
Example: Example::
# drivers/scsi/Makefile # drivers/scsi/Makefile
CFLAGS_aha152x.o = -DAHA152X_STAT -DAUTOCONF CFLAGS_aha152x.o = -DAHA152X_STAT -DAUTOCONF
CFLAGS_gdth.o = # -DDEBUG_GDTH=2 -D__SERIAL__ -D__COM2__ \ CFLAGS_gdth.o = # -DDEBUG_GDTH=2 -D__SERIAL__ -D__COM2__ \
...@@ -347,24 +372,27 @@ more details, with real examples. ...@@ -347,24 +372,27 @@ more details, with real examples.
$(AFLAGS_$@) is a similar feature for source files in assembly $(AFLAGS_$@) is a similar feature for source files in assembly
languages. languages.
Example: Example::
# arch/arm/kernel/Makefile # arch/arm/kernel/Makefile
AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET) AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET)
AFLAGS_crunch-bits.o := -Wa,-mcpu=ep9312 AFLAGS_crunch-bits.o := -Wa,-mcpu=ep9312
AFLAGS_iwmmxt.o := -Wa,-mcpu=iwmmxt AFLAGS_iwmmxt.o := -Wa,-mcpu=iwmmxt
--- 3.9 Dependency tracking 3.9 Dependency tracking
-----------------------
Kbuild tracks dependencies on the following: Kbuild tracks dependencies on the following:
1) All prerequisite files (both *.c and *.h) 1) All prerequisite files (both `*.c` and `*.h`)
2) CONFIG_ options used in all prerequisite files 2) `CONFIG_` options used in all prerequisite files
3) Command-line used to compile target 3) Command-line used to compile target
Thus, if you change an option to $(CC) all affected files will Thus, if you change an option to $(CC) all affected files will
be re-compiled. be re-compiled.
--- 3.10 Special Rules 3.10 Special Rules
------------------
Special rules are used when the kbuild infrastructure does Special rules are used when the kbuild infrastructure does
not provide the required support. A typical example is not provide the required support. A typical example is
...@@ -389,13 +417,15 @@ more details, with real examples. ...@@ -389,13 +417,15 @@ more details, with real examples.
where the target is saved. Always use $(obj) when where the target is saved. Always use $(obj) when
referring to generated files. referring to generated files.
Example: Example::
#drivers/scsi/Makefile #drivers/scsi/Makefile
$(obj)/53c8xx_d.h: $(src)/53c7,8xx.scr $(src)/script_asm.pl $(obj)/53c8xx_d.h: $(src)/53c7,8xx.scr $(src)/script_asm.pl
$(CPP) -DCHIP=810 - < $< | ... $(src)/script_asm.pl $(CPP) -DCHIP=810 - < $< | ... $(src)/script_asm.pl
This is a special rule, following the normal syntax This is a special rule, following the normal syntax
required by make. required by make.
The target file depends on two prerequisite files. References The target file depends on two prerequisite files. References
to the target file are prefixed with $(obj), references to the target file are prefixed with $(obj), references
to prerequisites are referenced with $(src) (because they are not to prerequisites are referenced with $(src) (because they are not
...@@ -408,14 +438,16 @@ more details, with real examples. ...@@ -408,14 +438,16 @@ more details, with real examples.
To support this kbuild defines $(kecho) which will echo out the To support this kbuild defines $(kecho) which will echo out the
text following $(kecho) to stdout except if "make -s" is used. text following $(kecho) to stdout except if "make -s" is used.
Example: Example::
#arch/blackfin/boot/Makefile #arch/blackfin/boot/Makefile
$(obj)/vmImage: $(obj)/vmlinux.gz $(obj)/vmImage: $(obj)/vmlinux.gz
$(call if_changed,uimage) $(call if_changed,uimage)
@$(kecho) 'Kernel: $@ is ready' @$(kecho) 'Kernel: $@ is ready'
--- 3.11 $(CC) support functions 3.11 $(CC) support functions
----------------------------
The kernel may be built with several different versions of The kernel may be built with several different versions of
$(CC), each supporting a unique set of features and options. $(CC), each supporting a unique set of features and options.
...@@ -425,10 +457,11 @@ more details, with real examples. ...@@ -425,10 +457,11 @@ more details, with real examples.
as-option as-option
as-option is used to check if $(CC) -- when used to compile as-option is used to check if $(CC) -- when used to compile
assembler (*.S) files -- supports the given option. An optional assembler (`*.S`) files -- supports the given option. An optional
second option may be specified if the first option is not supported. second option may be specified if the first option is not supported.
Example: Example::
#arch/sh/Makefile #arch/sh/Makefile
cflags-y += $(call as-option,-Wa$(comma)-isa=$(isa-y),) cflags-y += $(call as-option,-Wa$(comma)-isa=$(isa-y),)
...@@ -437,6 +470,21 @@ more details, with real examples. ...@@ -437,6 +470,21 @@ more details, with real examples.
The second argument is optional, and if supplied will be used The second argument is optional, and if supplied will be used
if first argument is not supported. if first argument is not supported.
cc-ldoption
cc-ldoption is used to check if $(CC) when used to link object files
supports the given option. An optional second option may be
specified if first option are not supported.
Example::
#arch/x86/kernel/Makefile
vsyscall-flags += $(call cc-ldoption, -Wl$(comma)--hash-style=sysv)
In the above example, vsyscall-flags will be assigned the option
-Wl$(comma)--hash-style=sysv if it is supported by $(CC).
The second argument is optional, and if supplied will be used
if first argument is not supported.
as-instr as-instr
as-instr checks if the assembler reports a specific instruction as-instr checks if the assembler reports a specific instruction
and then outputs either option1 or option2 and then outputs either option1 or option2
...@@ -447,7 +495,8 @@ more details, with real examples. ...@@ -447,7 +495,8 @@ more details, with real examples.
cc-option is used to check if $(CC) supports a given option, and if cc-option is used to check if $(CC) supports a given option, and if
not supported to use an optional second option. not supported to use an optional second option.
Example: Example::
#arch/x86/Makefile #arch/x86/Makefile
cflags-y += $(call cc-option,-march=pentium-mmx,-march=i586) cflags-y += $(call cc-option,-march=pentium-mmx,-march=i586)
...@@ -461,7 +510,8 @@ more details, with real examples. ...@@ -461,7 +510,8 @@ more details, with real examples.
cc-option-yn is used to check if gcc supports a given option cc-option-yn is used to check if gcc supports a given option
and return 'y' if supported, otherwise 'n'. and return 'y' if supported, otherwise 'n'.
Example: Example::
#arch/ppc/Makefile #arch/ppc/Makefile
biarch := $(call cc-option-yn, -m32) biarch := $(call cc-option-yn, -m32)
aflags-$(biarch) += -a32 aflags-$(biarch) += -a32
...@@ -479,7 +529,8 @@ more details, with real examples. ...@@ -479,7 +529,8 @@ more details, with real examples.
because gcc 4.4 and later accept any unknown -Wno-* option and only because gcc 4.4 and later accept any unknown -Wno-* option and only
warn about it if there is another warning in the source file. warn about it if there is another warning in the source file.
Example: Example::
KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable) KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
In the above example, -Wno-unused-but-set-variable will be added to In the above example, -Wno-unused-but-set-variable will be added to
...@@ -490,7 +541,8 @@ more details, with real examples. ...@@ -490,7 +541,8 @@ more details, with real examples.
if version expression is true, or the fifth (if given) if the version if version expression is true, or the fifth (if given) if the version
expression is false. expression is false.
Example: Example::
#fs/reiserfs/Makefile #fs/reiserfs/Makefile
ccflags-y := $(call cc-ifversion, -lt, 0402, -O1) ccflags-y := $(call cc-ifversion, -lt, 0402, -O1)
...@@ -515,7 +567,8 @@ more details, with real examples. ...@@ -515,7 +567,8 @@ more details, with real examples.
build (host arch is different from target arch). And if CROSS_COMPILE build (host arch is different from target arch). And if CROSS_COMPILE
is already set then leave it with the old value. is already set then leave it with the old value.
Example: Example::
#arch/m68k/Makefile #arch/m68k/Makefile
ifneq ($(SUBARCH),$(ARCH)) ifneq ($(SUBARCH),$(ARCH))
ifeq ($(CROSS_COMPILE),) ifeq ($(CROSS_COMPILE),)
...@@ -523,7 +576,8 @@ more details, with real examples. ...@@ -523,7 +576,8 @@ more details, with real examples.
endif endif
endif endif
--- 3.12 $(LD) support functions 3.12 $(LD) support functions
----------------------------
ld-option ld-option
ld-option is used to check if $(LD) supports the supplied option. ld-option is used to check if $(LD) supports the supplied option.
...@@ -531,12 +585,14 @@ more details, with real examples. ...@@ -531,12 +585,14 @@ more details, with real examples.
The second argument is an optional option that can be used if the The second argument is an optional option that can be used if the
first option is not supported by $(LD). first option is not supported by $(LD).
Example: Example::
#Makefile #Makefile
LDFLAGS_vmlinux += $(call ld-option, -X) LDFLAGS_vmlinux += $(call ld-option, -X)
=== 4 Host Program support 4 Host Program support
======================
Kbuild supports building executables on the host for use during the Kbuild supports building executables on the host for use during the
compilation stage. compilation stage.
...@@ -550,21 +606,24 @@ This can be done in two ways. Either add the dependency in a rule, ...@@ -550,21 +606,24 @@ This can be done in two ways. Either add the dependency in a rule,
or utilise the variable $(always). or utilise the variable $(always).
Both possibilities are described in the following. Both possibilities are described in the following.
--- 4.1 Simple Host Program 4.1 Simple Host Program
-----------------------
In some cases there is a need to compile and run a program on the In some cases there is a need to compile and run a program on the
computer where the build is running. computer where the build is running.
The following line tells kbuild that the program bin2hex shall be The following line tells kbuild that the program bin2hex shall be
built on the build host. built on the build host.
Example: Example::
hostprogs-y := bin2hex hostprogs-y := bin2hex
Kbuild assumes in the above example that bin2hex is made from a single Kbuild assumes in the above example that bin2hex is made from a single
c-source file named bin2hex.c located in the same directory as c-source file named bin2hex.c located in the same directory as
the Makefile. the Makefile.
--- 4.2 Composite Host Programs 4.2 Composite Host Programs
---------------------------
Host programs can be made up based on composite objects. Host programs can be made up based on composite objects.
The syntax used to define composite objects for host programs is The syntax used to define composite objects for host programs is
...@@ -572,7 +631,8 @@ Both possibilities are described in the following. ...@@ -572,7 +631,8 @@ Both possibilities are described in the following.
$(<executable>-objs) lists all objects used to link the final $(<executable>-objs) lists all objects used to link the final
executable. executable.
Example: Example::
#scripts/lxdialog/Makefile #scripts/lxdialog/Makefile
hostprogs-y := lxdialog hostprogs-y := lxdialog
lxdialog-objs := checklist.o lxdialog.o lxdialog-objs := checklist.o lxdialog.o
...@@ -580,16 +640,19 @@ Both possibilities are described in the following. ...@@ -580,16 +640,19 @@ Both possibilities are described in the following.
Objects with extension .o are compiled from the corresponding .c Objects with extension .o are compiled from the corresponding .c
files. In the above example, checklist.c is compiled to checklist.o files. In the above example, checklist.c is compiled to checklist.o
and lxdialog.c is compiled to lxdialog.o. and lxdialog.c is compiled to lxdialog.o.
Finally, the two .o files are linked to the executable, lxdialog. Finally, the two .o files are linked to the executable, lxdialog.
Note: The syntax <executable>-y is not permitted for host-programs. Note: The syntax <executable>-y is not permitted for host-programs.
--- 4.3 Using C++ for host programs 4.3 Using C++ for host programs
-------------------------------
kbuild offers support for host programs written in C++. This was kbuild offers support for host programs written in C++. This was
introduced solely to support kconfig, and is not recommended introduced solely to support kconfig, and is not recommended
for general use. for general use.
Example: Example::
#scripts/kconfig/Makefile #scripts/kconfig/Makefile
hostprogs-y := qconf hostprogs-y := qconf
qconf-cxxobjs := qconf.o qconf-cxxobjs := qconf.o
...@@ -600,13 +663,15 @@ Both possibilities are described in the following. ...@@ -600,13 +663,15 @@ Both possibilities are described in the following.
If qconf is composed of a mixture of .c and .cc files, then an If qconf is composed of a mixture of .c and .cc files, then an
additional line can be used to identify this. additional line can be used to identify this.
Example: Example::
#scripts/kconfig/Makefile #scripts/kconfig/Makefile
hostprogs-y := qconf hostprogs-y := qconf
qconf-cxxobjs := qconf.o qconf-cxxobjs := qconf.o
qconf-objs := check.o qconf-objs := check.o
--- 4.4 Controlling compiler options for host programs 4.4 Controlling compiler options for host programs
--------------------------------------------------
When compiling host programs, it is possible to set specific flags. When compiling host programs, it is possible to set specific flags.
The programs will always be compiled utilising $(HOSTCC) passed The programs will always be compiled utilising $(HOSTCC) passed
...@@ -614,27 +679,31 @@ Both possibilities are described in the following. ...@@ -614,27 +679,31 @@ Both possibilities are described in the following.
To set flags that will take effect for all host programs created To set flags that will take effect for all host programs created
in that Makefile, use the variable HOST_EXTRACFLAGS. in that Makefile, use the variable HOST_EXTRACFLAGS.
Example: Example::
#scripts/lxdialog/Makefile #scripts/lxdialog/Makefile
HOST_EXTRACFLAGS += -I/usr/include/ncurses HOST_EXTRACFLAGS += -I/usr/include/ncurses
To set specific flags for a single file the following construction To set specific flags for a single file the following construction
is used: is used:
Example: Example::
#arch/ppc64/boot/Makefile #arch/ppc64/boot/Makefile
HOSTCFLAGS_piggyback.o := -DKERNELBASE=$(KERNELBASE) HOSTCFLAGS_piggyback.o := -DKERNELBASE=$(KERNELBASE)
It is also possible to specify additional options to the linker. It is also possible to specify additional options to the linker.
Example: Example::
#scripts/kconfig/Makefile #scripts/kconfig/Makefile
HOSTLDLIBS_qconf := -L$(QTDIR)/lib HOSTLDLIBS_qconf := -L$(QTDIR)/lib
When linking qconf, it will be passed the extra option When linking qconf, it will be passed the extra option
"-L$(QTDIR)/lib". "-L$(QTDIR)/lib".
--- 4.5 When host programs are actually built 4.5 When host programs are actually built
-----------------------------------------
Kbuild will only build host-programs when they are referenced Kbuild will only build host-programs when they are referenced
as a prerequisite. as a prerequisite.
...@@ -642,7 +711,8 @@ Both possibilities are described in the following. ...@@ -642,7 +711,8 @@ Both possibilities are described in the following.
(1) List the prerequisite explicitly in a special rule. (1) List the prerequisite explicitly in a special rule.
Example: Example::
#drivers/pci/Makefile #drivers/pci/Makefile
hostprogs-y := gen-devlist hostprogs-y := gen-devlist
$(obj)/devlist.h: $(src)/pci.ids $(obj)/gen-devlist $(obj)/devlist.h: $(src)/pci.ids $(obj)/gen-devlist
...@@ -653,11 +723,13 @@ Both possibilities are described in the following. ...@@ -653,11 +723,13 @@ Both possibilities are described in the following.
the host programs in special rules must be prefixed with $(obj). the host programs in special rules must be prefixed with $(obj).
(2) Use $(always) (2) Use $(always)
When there is no suitable special rule, and the host program When there is no suitable special rule, and the host program
shall be built when a makefile is entered, the $(always) shall be built when a makefile is entered, the $(always)
variable shall be used. variable shall be used.
Example: Example::
#scripts/lxdialog/Makefile #scripts/lxdialog/Makefile
hostprogs-y := lxdialog hostprogs-y := lxdialog
always := $(hostprogs-y) always := $(hostprogs-y)
...@@ -665,11 +737,13 @@ Both possibilities are described in the following. ...@@ -665,11 +737,13 @@ Both possibilities are described in the following.
This will tell kbuild to build lxdialog even if not referenced in This will tell kbuild to build lxdialog even if not referenced in
any rule. any rule.
--- 4.6 Using hostprogs-$(CONFIG_FOO) 4.6 Using hostprogs-$(CONFIG_FOO)
---------------------------------
A typical pattern in a Kbuild file looks like this: A typical pattern in a Kbuild file looks like this:
Example: Example::
#scripts/Makefile #scripts/Makefile
hostprogs-$(CONFIG_KALLSYMS) += kallsyms hostprogs-$(CONFIG_KALLSYMS) += kallsyms
...@@ -679,7 +753,8 @@ Both possibilities are described in the following. ...@@ -679,7 +753,8 @@ Both possibilities are described in the following.
like hostprogs-y. But only hostprogs-y is recommended to be used like hostprogs-y. But only hostprogs-y is recommended to be used
when no CONFIG symbols are involved. when no CONFIG symbols are involved.
=== 5 Kbuild clean infrastructure 5 Kbuild clean infrastructure
=============================
"make clean" deletes most generated files in the obj tree where the kernel "make clean" deletes most generated files in the obj tree where the kernel
is compiled. This includes generated files such as host programs. is compiled. This includes generated files such as host programs.
...@@ -691,7 +766,8 @@ generated by kbuild are deleted all over the kernel src tree when ...@@ -691,7 +766,8 @@ generated by kbuild are deleted all over the kernel src tree when
Additional files can be specified in kbuild makefiles by use of $(clean-files). Additional files can be specified in kbuild makefiles by use of $(clean-files).
Example: Example::
#lib/Makefile #lib/Makefile
clean-files := crc32table.h clean-files := crc32table.h
...@@ -701,7 +777,8 @@ Makefile, except if prefixed with $(objtree). ...@@ -701,7 +777,8 @@ Makefile, except if prefixed with $(objtree).
To delete a directory hierarchy use: To delete a directory hierarchy use:
Example: Example::
#scripts/package/Makefile #scripts/package/Makefile
clean-dirs := $(objtree)/debian/ clean-dirs := $(objtree)/debian/
...@@ -711,7 +788,8 @@ subdirectories. ...@@ -711,7 +788,8 @@ subdirectories.
To exclude certain files from make clean, use the $(no-clean-files) variable. To exclude certain files from make clean, use the $(no-clean-files) variable.
This is only a special case used in the top level Kbuild file: This is only a special case used in the top level Kbuild file:
Example: Example::
#Kbuild #Kbuild
no-clean-files := $(bounds-file) $(offsets-file) no-clean-files := $(bounds-file) $(offsets-file)
...@@ -719,7 +797,8 @@ Usually kbuild descends down in subdirectories due to "obj-* := dir/", ...@@ -719,7 +797,8 @@ Usually kbuild descends down in subdirectories due to "obj-* := dir/",
but in the architecture makefiles where the kbuild infrastructure but in the architecture makefiles where the kbuild infrastructure
is not sufficient this sometimes needs to be explicit. is not sufficient this sometimes needs to be explicit.
Example: Example::
#arch/x86/boot/Makefile #arch/x86/boot/Makefile
subdir- := compressed/ subdir- := compressed/
...@@ -729,7 +808,8 @@ directory compressed/ when "make clean" is executed. ...@@ -729,7 +808,8 @@ directory compressed/ when "make clean" is executed.
To support the clean infrastructure in the Makefiles that build the To support the clean infrastructure in the Makefiles that build the
final bootimage there is an optional target named archclean: final bootimage there is an optional target named archclean:
Example: Example::
#arch/x86/Makefile #arch/x86/Makefile
archclean: archclean:
$(Q)$(MAKE) $(clean)=arch/x86/boot $(Q)$(MAKE) $(clean)=arch/x86/boot
...@@ -745,7 +825,8 @@ is not operational at that point. ...@@ -745,7 +825,8 @@ is not operational at that point.
Note 2: All directories listed in core-y, libs-y, drivers-y and net-y will Note 2: All directories listed in core-y, libs-y, drivers-y and net-y will
be visited during "make clean". be visited during "make clean".
=== 6 Architecture Makefiles 6 Architecture Makefiles
========================
The top level Makefile sets up the environment and does the preparation, The top level Makefile sets up the environment and does the preparation,
before starting to descend down in the individual directories. before starting to descend down in the individual directories.
...@@ -756,6 +837,7 @@ To do so, arch/$(ARCH)/Makefile sets up a number of variables and defines ...@@ -756,6 +837,7 @@ To do so, arch/$(ARCH)/Makefile sets up a number of variables and defines
a few targets. a few targets.
When kbuild executes, the following steps are followed (roughly): When kbuild executes, the following steps are followed (roughly):
1) Configuration of the kernel => produce .config 1) Configuration of the kernel => produce .config
2) Store kernel version in include/linux/version.h 2) Store kernel version in include/linux/version.h
3) Updating all other prerequisites to the target prepare: 3) Updating all other prerequisites to the target prepare:
...@@ -773,37 +855,45 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -773,37 +855,45 @@ When kbuild executes, the following steps are followed (roughly):
- Preparing initrd images and the like - Preparing initrd images and the like
--- 6.1 Set variables to tweak the build to the architecture 6.1 Set variables to tweak the build to the architecture
--------------------------------------------------------
LDFLAGS Generic $(LD) options LDFLAGS
Generic $(LD) options
Flags used for all invocations of the linker. Flags used for all invocations of the linker.
Often specifying the emulation is sufficient. Often specifying the emulation is sufficient.
Example: Example::
#arch/s390/Makefile #arch/s390/Makefile
LDFLAGS := -m elf_s390 LDFLAGS := -m elf_s390
Note: ldflags-y can be used to further customise Note: ldflags-y can be used to further customise
the flags used. See chapter 3.7. the flags used. See chapter 3.7.
LDFLAGS_vmlinux Options for $(LD) when linking vmlinux LDFLAGS_vmlinux
Options for $(LD) when linking vmlinux
LDFLAGS_vmlinux is used to specify additional flags to pass to LDFLAGS_vmlinux is used to specify additional flags to pass to
the linker when linking the final vmlinux image. the linker when linking the final vmlinux image.
LDFLAGS_vmlinux uses the LDFLAGS_$@ support. LDFLAGS_vmlinux uses the LDFLAGS_$@ support.
Example: Example::
#arch/x86/Makefile #arch/x86/Makefile
LDFLAGS_vmlinux := -e stext LDFLAGS_vmlinux := -e stext
OBJCOPYFLAGS objcopy flags OBJCOPYFLAGS
objcopy flags
When $(call if_changed,objcopy) is used to translate a .o file, When $(call if_changed,objcopy) is used to translate a .o file,
the flags specified in OBJCOPYFLAGS will be used. the flags specified in OBJCOPYFLAGS will be used.
$(call if_changed,objcopy) is often used to generate raw binaries on $(call if_changed,objcopy) is often used to generate raw binaries on
vmlinux. vmlinux.
Example: Example::
#arch/s390/Makefile #arch/s390/Makefile
OBJCOPYFLAGS := -O binary OBJCOPYFLAGS := -O binary
...@@ -814,30 +904,34 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -814,30 +904,34 @@ When kbuild executes, the following steps are followed (roughly):
In this example, the binary $(obj)/image is a binary version of In this example, the binary $(obj)/image is a binary version of
vmlinux. The usage of $(call if_changed,xxx) will be described later. vmlinux. The usage of $(call if_changed,xxx) will be described later.
KBUILD_AFLAGS $(AS) assembler flags KBUILD_AFLAGS
$(AS) assembler flags
Default value - see top level Makefile Default value - see top level Makefile
Append or modify as required per architecture. Append or modify as required per architecture.
Example: Example::
#arch/sparc64/Makefile #arch/sparc64/Makefile
KBUILD_AFLAGS += -m64 -mcpu=ultrasparc KBUILD_AFLAGS += -m64 -mcpu=ultrasparc
KBUILD_CFLAGS $(CC) compiler flags KBUILD_CFLAGS
$(CC) compiler flags
Default value - see top level Makefile Default value - see top level Makefile
Append or modify as required per architecture. Append or modify as required per architecture.
Often, the KBUILD_CFLAGS variable depends on the configuration. Often, the KBUILD_CFLAGS variable depends on the configuration.
Example: Example::
#arch/x86/boot/compressed/Makefile #arch/x86/boot/compressed/Makefile
cflags-$(CONFIG_X86_32) := -march=i386 cflags-$(CONFIG_X86_32) := -march=i386
cflags-$(CONFIG_X86_64) := -mcmodel=small cflags-$(CONFIG_X86_64) := -mcmodel=small
KBUILD_CFLAGS += $(cflags-y) KBUILD_CFLAGS += $(cflags-y)
Many arch Makefiles dynamically run the target C compiler to Many arch Makefiles dynamically run the target C compiler to
probe supported options: probe supported options::
#arch/x86/Makefile #arch/x86/Makefile
...@@ -853,32 +947,39 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -853,32 +947,39 @@ When kbuild executes, the following steps are followed (roughly):
The first example utilises the trick that a config option expands The first example utilises the trick that a config option expands
to 'y' when selected. to 'y' when selected.
KBUILD_AFLAGS_KERNEL $(AS) options specific for built-in KBUILD_AFLAGS_KERNEL
$(AS) options specific for built-in
$(KBUILD_AFLAGS_KERNEL) contains extra C compiler flags used to compile $(KBUILD_AFLAGS_KERNEL) contains extra C compiler flags used to compile
resident kernel code. resident kernel code.
KBUILD_AFLAGS_MODULE Options for $(AS) when building modules KBUILD_AFLAGS_MODULE
Options for $(AS) when building modules
$(KBUILD_AFLAGS_MODULE) is used to add arch-specific options that $(KBUILD_AFLAGS_MODULE) is used to add arch-specific options that
are used for $(AS). are used for $(AS).
From commandline AFLAGS_MODULE shall be used (see kbuild.txt). From commandline AFLAGS_MODULE shall be used (see kbuild.txt).
KBUILD_CFLAGS_KERNEL $(CC) options specific for built-in KBUILD_CFLAGS_KERNEL
$(CC) options specific for built-in
$(KBUILD_CFLAGS_KERNEL) contains extra C compiler flags used to compile $(KBUILD_CFLAGS_KERNEL) contains extra C compiler flags used to compile
resident kernel code. resident kernel code.
KBUILD_CFLAGS_MODULE Options for $(CC) when building modules KBUILD_CFLAGS_MODULE
Options for $(CC) when building modules
$(KBUILD_CFLAGS_MODULE) is used to add arch-specific options that $(KBUILD_CFLAGS_MODULE) is used to add arch-specific options that
are used for $(CC). are used for $(CC).
From commandline CFLAGS_MODULE shall be used (see kbuild.txt). From commandline CFLAGS_MODULE shall be used (see kbuild.txt).
KBUILD_LDFLAGS_MODULE Options for $(LD) when linking modules KBUILD_LDFLAGS_MODULE
Options for $(LD) when linking modules
$(KBUILD_LDFLAGS_MODULE) is used to add arch-specific options $(KBUILD_LDFLAGS_MODULE) is used to add arch-specific options
used when linking modules. This is often a linker script. used when linking modules. This is often a linker script.
From commandline LDFLAGS_MODULE shall be used (see kbuild.txt). From commandline LDFLAGS_MODULE shall be used (see kbuild.txt).
KBUILD_ARFLAGS Options for $(AR) when creating archives KBUILD_ARFLAGS Options for $(AR) when creating archives
...@@ -894,7 +995,8 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -894,7 +995,8 @@ When kbuild executes, the following steps are followed (roughly):
means for an architecture to override the defaults. means for an architecture to override the defaults.
--- 6.2 Add prerequisites to archheaders: 6.2 Add prerequisites to archheaders
------------------------------------
The archheaders: rule is used to generate header files that The archheaders: rule is used to generate header files that
may be installed into user space by "make header_install" or may be installed into user space by "make header_install" or
...@@ -907,13 +1009,15 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -907,13 +1009,15 @@ When kbuild executes, the following steps are followed (roughly):
architecture itself. architecture itself.
--- 6.3 Add prerequisites to archprepare: 6.3 Add prerequisites to archprepare
------------------------------------
The archprepare: rule is used to list prerequisites that need to be The archprepare: rule is used to list prerequisites that need to be
built before starting to descend down in the subdirectories. built before starting to descend down in the subdirectories.
This is usually used for header files containing assembler constants. This is usually used for header files containing assembler constants.
Example: Example::
#arch/arm/Makefile #arch/arm/Makefile
archprepare: maketools archprepare: maketools
...@@ -923,7 +1027,8 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -923,7 +1027,8 @@ When kbuild executes, the following steps are followed (roughly):
generating offset header files. generating offset header files.
--- 6.4 List directories to visit when descending 6.4 List directories to visit when descending
---------------------------------------------
An arch Makefile cooperates with the top Makefile to define variables An arch Makefile cooperates with the top Makefile to define variables
which specify how to build the vmlinux file. Note that there is no which specify how to build the vmlinux file. Note that there is no
...@@ -932,27 +1037,33 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -932,27 +1037,33 @@ When kbuild executes, the following steps are followed (roughly):
head-y, init-y, core-y, libs-y, drivers-y, net-y head-y, init-y, core-y, libs-y, drivers-y, net-y
$(head-y) lists objects to be linked first in vmlinux. $(head-y) lists objects to be linked first in vmlinux.
$(libs-y) lists directories where a lib.a archive can be located. $(libs-y) lists directories where a lib.a archive can be located.
The rest list directories where a built-in.a object file can be The rest list directories where a built-in.a object file can be
located. located.
$(init-y) objects will be located after $(head-y). $(init-y) objects will be located after $(head-y).
Then the rest follows in this order: Then the rest follows in this order:
$(core-y), $(libs-y), $(drivers-y) and $(net-y). $(core-y), $(libs-y), $(drivers-y) and $(net-y).
The top level Makefile defines values for all generic directories, The top level Makefile defines values for all generic directories,
and arch/$(ARCH)/Makefile only adds architecture-specific directories. and arch/$(ARCH)/Makefile only adds architecture-specific
directories.
Example::
Example:
#arch/sparc64/Makefile #arch/sparc64/Makefile
core-y += arch/sparc64/kernel/ core-y += arch/sparc64/kernel/
libs-y += arch/sparc64/prom/ arch/sparc64/lib/ libs-y += arch/sparc64/prom/ arch/sparc64/lib/
drivers-$(CONFIG_OPROFILE) += arch/sparc64/oprofile/ drivers-$(CONFIG_OPROFILE) += arch/sparc64/oprofile/
--- 6.5 Architecture-specific boot images 6.5 Architecture-specific boot images
-------------------------------------
An arch Makefile specifies goals that take the vmlinux file, compress An arch Makefile specifies goals that take the vmlinux file, compress
it, wrap it in bootstrapping code, and copy the resulting files it, wrap it in bootstrapping code, and copy the resulting files
...@@ -970,7 +1081,8 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -970,7 +1081,8 @@ When kbuild executes, the following steps are followed (roughly):
arch/$(ARCH)/Makefile, and use the full path when calling down arch/$(ARCH)/Makefile, and use the full path when calling down
into the arch/$(ARCH)/boot/Makefile. into the arch/$(ARCH)/boot/Makefile.
Example: Example::
#arch/x86/Makefile #arch/x86/Makefile
boot := arch/x86/boot boot := arch/x86/boot
bzImage: vmlinux bzImage: vmlinux
...@@ -983,7 +1095,8 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -983,7 +1095,8 @@ When kbuild executes, the following steps are followed (roughly):
but executing "make help" will list all relevant targets. but executing "make help" will list all relevant targets.
To support this, $(archhelp) must be defined. To support this, $(archhelp) must be defined.
Example: Example::
#arch/x86/Makefile #arch/x86/Makefile
define archhelp define archhelp
echo '* bzImage - Image (arch/$(ARCH)/boot/bzImage)' echo '* bzImage - Image (arch/$(ARCH)/boot/bzImage)'
...@@ -997,25 +1110,30 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -997,25 +1110,30 @@ When kbuild executes, the following steps are followed (roughly):
Add a new prerequisite to all: to select a default goal different Add a new prerequisite to all: to select a default goal different
from vmlinux. from vmlinux.
Example: Example::
#arch/x86/Makefile #arch/x86/Makefile
all: bzImage all: bzImage
When "make" is executed without arguments, bzImage will be built. When "make" is executed without arguments, bzImage will be built.
--- 6.6 Building non-kbuild targets 6.6 Building non-kbuild targets
-------------------------------
extra-y extra-y
extra-y specifies additional targets created in the current extra-y specifies additional targets created in the current
directory, in addition to any targets specified by obj-*. directory, in addition to any targets specified by `obj-*`.
Listing all targets in extra-y is required for two purposes: Listing all targets in extra-y is required for two purposes:
1) Enable kbuild to check changes in command lines 1) Enable kbuild to check changes in command lines
- When $(call if_changed,xxx) is used - When $(call if_changed,xxx) is used
2) kbuild knows what files to delete during "make clean" 2) kbuild knows what files to delete during "make clean"
Example: Example::
#arch/x86/kernel/Makefile #arch/x86/kernel/Makefile
extra-y := head.o init_task.o extra-y := head.o init_task.o
...@@ -1023,16 +1141,17 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -1023,16 +1141,17 @@ When kbuild executes, the following steps are followed (roughly):
shall be built, but shall not be linked as part of built-in.a. shall be built, but shall not be linked as part of built-in.a.
--- 6.7 Commands useful for building a boot image 6.7 Commands useful for building a boot image
---------------------------------------------
Kbuild provides a few macros that are useful when building a Kbuild provides a few macros that are useful when building a
boot image. boot image.
if_changed if_changed
if_changed is the infrastructure used for the following commands. if_changed is the infrastructure used for the following commands.
Usage: Usage::
target: source(s) FORCE target: source(s) FORCE
$(call if_changed,ld/objcopy/gzip/...) $(call if_changed,ld/objcopy/gzip/...)
...@@ -1050,12 +1169,16 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -1050,12 +1169,16 @@ When kbuild executes, the following steps are followed (roughly):
Note: It is a typical mistake to forget the FORCE prerequisite. Note: It is a typical mistake to forget the FORCE prerequisite.
Another common pitfall is that whitespace is sometimes Another common pitfall is that whitespace is sometimes
significant; for instance, the below will fail (note the extra space significant; for instance, the below will fail (note the extra space
after the comma): after the comma)::
target: source(s) FORCE target: source(s) FORCE
#WRONG!# $(call if_changed, ld/objcopy/gzip/...)
Note: if_changed should not be used more than once per target. **WRONG!** $(call if_changed, ld/objcopy/gzip/...)
Note:
if_changed should not be used more than once per target.
It stores the executed command in a corresponding .cmd It stores the executed command in a corresponding .cmd
file and multiple calls would result in overwrites and file and multiple calls would result in overwrites and
unwanted results when the target is up to date and only the unwanted results when the target is up to date and only the
tests on changed commands trigger execution of commands. tests on changed commands trigger execution of commands.
...@@ -1063,7 +1186,8 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -1063,7 +1186,8 @@ When kbuild executes, the following steps are followed (roughly):
ld ld
Link target. Often, LDFLAGS_$@ is used to set specific options to ld. Link target. Often, LDFLAGS_$@ is used to set specific options to ld.
Example: Example::
#arch/x86/boot/Makefile #arch/x86/boot/Makefile
LDFLAGS_bootsect := -Ttext 0x0 -s --oformat binary LDFLAGS_bootsect := -Ttext 0x0 -s --oformat binary
LDFLAGS_setup := -Ttext 0x0 -s --oformat binary -e begtext LDFLAGS_setup := -Ttext 0x0 -s --oformat binary -e begtext
...@@ -1077,12 +1201,15 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -1077,12 +1201,15 @@ When kbuild executes, the following steps are followed (roughly):
LDFLAGS_$@ syntax - one for each potential target. LDFLAGS_$@ syntax - one for each potential target.
$(targets) are assigned all potential targets, by which kbuild knows $(targets) are assigned all potential targets, by which kbuild knows
the targets and will: the targets and will:
1) check for commandline changes 1) check for commandline changes
2) delete target during make clean 2) delete target during make clean
The ": %: %.o" part of the prerequisite is a shorthand that The ": %: %.o" part of the prerequisite is a shorthand that
frees us from listing the setup.o and bootsect.o files. frees us from listing the setup.o and bootsect.o files.
Note: It is a common mistake to forget the "targets :=" assignment,
Note:
It is a common mistake to forget the "targets :=" assignment,
resulting in the target file being recompiled for no resulting in the target file being recompiled for no
obvious reason. obvious reason.
...@@ -1094,7 +1221,8 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -1094,7 +1221,8 @@ When kbuild executes, the following steps are followed (roughly):
gzip gzip
Compress target. Use maximum compression to compress target. Compress target. Use maximum compression to compress target.
Example: Example::
#arch/x86/boot/compressed/Makefile #arch/x86/boot/compressed/Makefile
$(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y) FORCE $(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y) FORCE
$(call if_changed,gzip) $(call if_changed,gzip)
...@@ -1105,26 +1233,30 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -1105,26 +1233,30 @@ When kbuild executes, the following steps are followed (roughly):
in an init section in the image. Platform code *must* copy the in an init section in the image. Platform code *must* copy the
blob to non-init memory prior to calling unflatten_device_tree(). blob to non-init memory prior to calling unflatten_device_tree().
To use this command, simply add *.dtb into obj-y or targets, or make To use this command, simply add `*.dtb` into obj-y or targets, or make
some other target depend on %.dtb some other target depend on `%.dtb`
A central rule exists to create $(obj)/%.dtb from $(src)/%.dts; A central rule exists to create `$(obj)/%.dtb` from `$(src)/%.dts`;
architecture Makefiles do no need to explicitly write out that rule. architecture Makefiles do no need to explicitly write out that rule.
Example: Example::
targets += $(dtb-y) targets += $(dtb-y)
DTC_FLAGS ?= -p 1024 DTC_FLAGS ?= -p 1024
--- 6.8 Custom kbuild commands 6.8 Custom kbuild commands
--------------------------
When kbuild is executing with KBUILD_VERBOSE=0, then only a shorthand When kbuild is executing with KBUILD_VERBOSE=0, then only a shorthand
of a command is normally displayed. of a command is normally displayed.
To enable this behaviour for custom commands kbuild requires To enable this behaviour for custom commands kbuild requires
two variables to be set: two variables to be set::
quiet_cmd_<command> - what shall be echoed quiet_cmd_<command> - what shall be echoed
cmd_<command> - the command to execute cmd_<command> - the command to execute
Example: Example::
# #
quiet_cmd_image = BUILD $@ quiet_cmd_image = BUILD $@
cmd_image = $(obj)/tools/build $(BUILDFLAGS) \ cmd_image = $(obj)/tools/build $(BUILDFLAGS) \
...@@ -1135,7 +1267,7 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -1135,7 +1267,7 @@ When kbuild executes, the following steps are followed (roughly):
$(call if_changed,image) $(call if_changed,image)
@echo 'Kernel: $@ is ready' @echo 'Kernel: $@ is ready'
When updating the $(obj)/bzImage target, the line When updating the $(obj)/bzImage target, the line:
BUILD arch/x86/boot/bzImage BUILD arch/x86/boot/bzImage
...@@ -1148,9 +1280,10 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -1148,9 +1280,10 @@ When kbuild executes, the following steps are followed (roughly):
arch/$(ARCH)/kernel/vmlinux.lds is used. arch/$(ARCH)/kernel/vmlinux.lds is used.
The script is a preprocessed variant of the file vmlinux.lds.S The script is a preprocessed variant of the file vmlinux.lds.S
located in the same directory. located in the same directory.
kbuild knows .lds files and includes a rule *lds.S -> *lds. kbuild knows .lds files and includes a rule `*lds.S` -> `*lds`.
Example::
Example:
#arch/x86/kernel/Makefile #arch/x86/kernel/Makefile
always := vmlinux.lds always := vmlinux.lds
...@@ -1162,17 +1295,19 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -1162,17 +1295,19 @@ When kbuild executes, the following steps are followed (roughly):
The assignment to $(CPPFLAGS_vmlinux.lds) tells kbuild to use the The assignment to $(CPPFLAGS_vmlinux.lds) tells kbuild to use the
specified options when building the target vmlinux.lds. specified options when building the target vmlinux.lds.
When building the *.lds target, kbuild uses the variables: When building the `*.lds` target, kbuild uses the variables::
KBUILD_CPPFLAGS : Set in top-level Makefile KBUILD_CPPFLAGS : Set in top-level Makefile
cppflags-y : May be set in the kbuild makefile cppflags-y : May be set in the kbuild makefile
CPPFLAGS_$(@F) : Target-specific flags. CPPFLAGS_$(@F) : Target-specific flags.
Note that the full filename is used in this Note that the full filename is used in this
assignment. assignment.
The kbuild infrastructure for *lds files is used in several The kbuild infrastructure for `*lds` files is used in several
architecture-specific files. architecture-specific files.
--- 6.10 Generic header files 6.10 Generic header files
-------------------------
The directory include/asm-generic contains the header files The directory include/asm-generic contains the header files
that may be shared between individual architectures. that may be shared between individual architectures.
...@@ -1180,7 +1315,8 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -1180,7 +1315,8 @@ When kbuild executes, the following steps are followed (roughly):
to list the file in the Kbuild file. to list the file in the Kbuild file.
See "7.2 generic-y" for further info on syntax etc. See "7.2 generic-y" for further info on syntax etc.
--- 6.11 Post-link pass 6.11 Post-link pass
-------------------
If the file arch/xxx/Makefile.postlink exists, this makefile If the file arch/xxx/Makefile.postlink exists, this makefile
will be invoked for post-link objects (vmlinux and modules.ko) will be invoked for post-link objects (vmlinux and modules.ko)
...@@ -1195,15 +1331,17 @@ When kbuild executes, the following steps are followed (roughly): ...@@ -1195,15 +1331,17 @@ When kbuild executes, the following steps are followed (roughly):
For example, powerpc uses this to check relocation sanity of For example, powerpc uses this to check relocation sanity of
the linked vmlinux file. the linked vmlinux file.
=== 7 Kbuild syntax for exported headers 7 Kbuild syntax for exported headers
------------------------------------
The kernel includes a set of headers that is exported to userspace. The kernel includes a set of headers that is exported to userspace.
Many headers can be exported as-is but other headers require a Many headers can be exported as-is but other headers require a
minimal pre-processing before they are ready for user-space. minimal pre-processing before they are ready for user-space.
The pre-processing does: The pre-processing does:
- drop kernel-specific annotations - drop kernel-specific annotations
- drop include of compiler.h - drop include of compiler.h
- drop all sections that are kernel internal (guarded by ifdef __KERNEL__) - drop all sections that are kernel internal (guarded by `ifdef __KERNEL__`)
All headers under include/uapi/, include/generated/uapi/, All headers under include/uapi/, include/generated/uapi/,
arch/<arch>/include/uapi/ and arch/<arch>/include/generated/uapi/ arch/<arch>/include/uapi/ and arch/<arch>/include/generated/uapi/
...@@ -1213,40 +1351,45 @@ A Kbuild file may be defined under arch/<arch>/include/uapi/asm/ and ...@@ -1213,40 +1351,45 @@ A Kbuild file may be defined under arch/<arch>/include/uapi/asm/ and
arch/<arch>/include/asm/ to list asm files coming from asm-generic. arch/<arch>/include/asm/ to list asm files coming from asm-generic.
See subsequent chapter for the syntax of the Kbuild file. See subsequent chapter for the syntax of the Kbuild file.
--- 7.1 no-export-headers 7.1 no-export-headers
---------------------
no-export-headers is essentially used by include/uapi/linux/Kbuild to no-export-headers is essentially used by include/uapi/linux/Kbuild to
avoid exporting specific headers (e.g. kvm.h) on architectures that do avoid exporting specific headers (e.g. kvm.h) on architectures that do
not support it. It should be avoided as much as possible. not support it. It should be avoided as much as possible.
--- 7.2 generic-y 7.2 generic-y
-------------
If an architecture uses a verbatim copy of a header from If an architecture uses a verbatim copy of a header from
include/asm-generic then this is listed in the file include/asm-generic then this is listed in the file
arch/$(ARCH)/include/asm/Kbuild like this: arch/$(ARCH)/include/asm/Kbuild like this:
Example: Example::
#arch/x86/include/asm/Kbuild #arch/x86/include/asm/Kbuild
generic-y += termios.h generic-y += termios.h
generic-y += rtc.h generic-y += rtc.h
During the prepare phase of the build a wrapper include During the prepare phase of the build a wrapper include
file is generated in the directory: file is generated in the directory::
arch/$(ARCH)/include/generated/asm arch/$(ARCH)/include/generated/asm
When a header is exported where the architecture uses When a header is exported where the architecture uses
the generic header a similar wrapper is generated as part the generic header a similar wrapper is generated as part
of the set of exported headers in the directory: of the set of exported headers in the directory::
usr/include/asm usr/include/asm
The generated wrapper will in both cases look like the following: The generated wrapper will in both cases look like the following:
Example: termios.h Example: termios.h::
#include <asm-generic/termios.h> #include <asm-generic/termios.h>
--- 7.3 generated-y 7.3 generated-y
---------------
If an architecture generates other header files alongside generic-y If an architecture generates other header files alongside generic-y
wrappers, generated-y specifies them. wrappers, generated-y specifies them.
...@@ -1254,11 +1397,13 @@ See subsequent chapter for the syntax of the Kbuild file. ...@@ -1254,11 +1397,13 @@ See subsequent chapter for the syntax of the Kbuild file.
This prevents them being treated as stale asm-generic wrappers and This prevents them being treated as stale asm-generic wrappers and
removed. removed.
Example: Example::
#arch/x86/include/asm/Kbuild #arch/x86/include/asm/Kbuild
generated-y += syscalls_32.h generated-y += syscalls_32.h
--- 7.4 mandatory-y 7.4 mandatory-y
---------------
mandatory-y is essentially used by include/(uapi/)asm-generic/Kbuild mandatory-y is essentially used by include/(uapi/)asm-generic/Kbuild
to define the minimum set of ASM headers that all architectures must have. to define the minimum set of ASM headers that all architectures must have.
...@@ -1270,12 +1415,12 @@ See subsequent chapter for the syntax of the Kbuild file. ...@@ -1270,12 +1415,12 @@ See subsequent chapter for the syntax of the Kbuild file.
The convention is to list one subdir per line and The convention is to list one subdir per line and
preferably in alphabetic order. preferably in alphabetic order.
=== 8 Kbuild Variables 8 Kbuild Variables
==================
The top Makefile exports the following variables: The top Makefile exports the following variables:
VERSION, PATCHLEVEL, SUBLEVEL, EXTRAVERSION VERSION, PATCHLEVEL, SUBLEVEL, EXTRAVERSION
These variables define the current kernel version. A few arch These variables define the current kernel version. A few arch
Makefiles actually use these values directly; they should use Makefiles actually use these values directly; they should use
$(KERNELRELEASE) instead. $(KERNELRELEASE) instead.
...@@ -1289,32 +1434,28 @@ The top Makefile exports the following variables: ...@@ -1289,32 +1434,28 @@ The top Makefile exports the following variables:
such as "-pre4", and is often blank. such as "-pre4", and is often blank.
KERNELRELEASE KERNELRELEASE
$(KERNELRELEASE) is a single string such as "2.4.0-pre4", suitable $(KERNELRELEASE) is a single string such as "2.4.0-pre4", suitable
for constructing installation directory names or showing in for constructing installation directory names or showing in
version strings. Some arch Makefiles use it for this purpose. version strings. Some arch Makefiles use it for this purpose.
ARCH ARCH
This variable defines the target architecture, such as "i386", This variable defines the target architecture, such as "i386",
"arm", or "sparc". Some kbuild Makefiles test $(ARCH) to "arm", or "sparc". Some kbuild Makefiles test $(ARCH) to
determine which files to compile. determine which files to compile.
By default, the top Makefile sets $(ARCH) to be the same as the By default, the top Makefile sets $(ARCH) to be the same as the
host system architecture. For a cross build, a user may host system architecture. For a cross build, a user may
override the value of $(ARCH) on the command line: override the value of $(ARCH) on the command line::
make ARCH=m68k ... make ARCH=m68k ...
INSTALL_PATH INSTALL_PATH
This variable defines a place for the arch Makefiles to install This variable defines a place for the arch Makefiles to install
the resident kernel image and System.map file. the resident kernel image and System.map file.
Use this for architecture-specific install targets. Use this for architecture-specific install targets.
INSTALL_MOD_PATH, MODLIB INSTALL_MOD_PATH, MODLIB
$(INSTALL_MOD_PATH) specifies a prefix to $(MODLIB) for module $(INSTALL_MOD_PATH) specifies a prefix to $(MODLIB) for module
installation. This variable is not defined in the Makefile but installation. This variable is not defined in the Makefile but
may be passed in by the user if desired. may be passed in by the user if desired.
...@@ -1325,7 +1466,6 @@ The top Makefile exports the following variables: ...@@ -1325,7 +1466,6 @@ The top Makefile exports the following variables:
override this value on the command line if desired. override this value on the command line if desired.
INSTALL_MOD_STRIP INSTALL_MOD_STRIP
If this variable is specified, it will cause modules to be stripped If this variable is specified, it will cause modules to be stripped
after they are installed. If INSTALL_MOD_STRIP is '1', then the after they are installed. If INSTALL_MOD_STRIP is '1', then the
default option --strip-debug will be used. Otherwise, the default option --strip-debug will be used. Otherwise, the
...@@ -1333,7 +1473,8 @@ The top Makefile exports the following variables: ...@@ -1333,7 +1473,8 @@ The top Makefile exports the following variables:
command. command.
=== 9 Makefile language 9 Makefile language
===================
The kernel Makefiles are designed to be run with GNU Make. The Makefiles The kernel Makefiles are designed to be run with GNU Make. The Makefiles
use only the documented features of GNU Make, but they do use many use only the documented features of GNU Make, but they do use many
...@@ -1352,18 +1493,17 @@ time the left-hand side is used. ...@@ -1352,18 +1493,17 @@ time the left-hand side is used.
There are some cases where "=" is appropriate. Usually, though, ":=" There are some cases where "=" is appropriate. Usually, though, ":="
is the right choice. is the right choice.
=== 10 Credits 10 Credits
==========
Original version made by Michael Elizabeth Chastain, <mailto:mec@shout.net> - Original version made by Michael Elizabeth Chastain, <mailto:mec@shout.net>
Updates by Kai Germaschewski <kai@tp1.ruhr-uni-bochum.de> - Updates by Kai Germaschewski <kai@tp1.ruhr-uni-bochum.de>
Updates by Sam Ravnborg <sam@ravnborg.org> - Updates by Sam Ravnborg <sam@ravnborg.org>
Language QA by Jan Engelhardt <jengelh@gmx.de> - Language QA by Jan Engelhardt <jengelh@gmx.de>
=== 11 TODO 11 TODO
=======
- Describe how kbuild supports shipped files with _shipped. - Describe how kbuild supports shipped files with _shipped.
- Generating offset header files. - Generating offset header files.
- Add more variables to section 7? - Add more variables to section 7?
Documentation/kbuild/modules.txt → Documentation/kbuild/modules.rst
View file @ cd238eff
=========================
Building External Modules Building External Modules
=========================
This document describes how to build an out-of-tree kernel module. This document describes how to build an out-of-tree kernel module.
=== Table of Contents .. Table of Contents
=== 1 Introduction === 1 Introduction
=== 2 How to Build External Modules === 2 How to Build External Modules
...@@ -31,7 +33,8 @@ This document describes how to build an out-of-tree kernel module. ...@@ -31,7 +33,8 @@ This document describes how to build an out-of-tree kernel module.
=== 1. Introduction 1. Introduction
===============
"kbuild" is the build system used by the Linux kernel. Modules must use "kbuild" is the build system used by the Linux kernel. Modules must use
kbuild to stay compatible with changes in the build infrastructure and kbuild to stay compatible with changes in the build infrastructure and
...@@ -48,7 +51,8 @@ easily accomplished, and a complete example will be presented in ...@@ -48,7 +51,8 @@ easily accomplished, and a complete example will be presented in
section 3. section 3.
=== 2. How to Build External Modules 2. How to Build External Modules
================================
To build external modules, you must have a prebuilt kernel available To build external modules, you must have a prebuilt kernel available
that contains the configuration and header files used in the build. that contains the configuration and header files used in the build.
...@@ -65,25 +69,27 @@ NOTE: "modules_prepare" will not build Module.symvers even if ...@@ -65,25 +69,27 @@ NOTE: "modules_prepare" will not build Module.symvers even if
CONFIG_MODVERSIONS is set; therefore, a full kernel build needs to be CONFIG_MODVERSIONS is set; therefore, a full kernel build needs to be
executed to make module versioning work. executed to make module versioning work.
--- 2.1 Command Syntax 2.1 Command Syntax
==================
The command to build an external module is: The command to build an external module is::
$ make -C <path_to_kernel_src> M=$PWD $ make -C <path_to_kernel_src> M=$PWD
The kbuild system knows that an external module is being built The kbuild system knows that an external module is being built
due to the "M=<dir>" option given in the command. due to the "M=<dir>" option given in the command.
To build against the running kernel use: To build against the running kernel use::
$ make -C /lib/modules/`uname -r`/build M=$PWD $ make -C /lib/modules/`uname -r`/build M=$PWD
Then to install the module(s) just built, add the target Then to install the module(s) just built, add the target
"modules_install" to the command: "modules_install" to the command::
$ make -C /lib/modules/`uname -r`/build M=$PWD modules_install $ make -C /lib/modules/`uname -r`/build M=$PWD modules_install
--- 2.2 Options 2.2 Options
===========
($KDIR refers to the path of the kernel source directory.) ($KDIR refers to the path of the kernel source directory.)
...@@ -100,7 +106,8 @@ executed to make module versioning work. ...@@ -100,7 +106,8 @@ executed to make module versioning work.
directory where the external module (kbuild file) is directory where the external module (kbuild file) is
located. located.
--- 2.3 Targets 2.3 Targets
===========
When building an external module, only a subset of the "make" When building an external module, only a subset of the "make"
targets are available. targets are available.
...@@ -130,26 +137,29 @@ executed to make module versioning work. ...@@ -130,26 +137,29 @@ executed to make module versioning work.
help help
List the available targets for external modules. List the available targets for external modules.
--- 2.4 Building Separate Files 2.4 Building Separate Files
===========================
It is possible to build single files that are part of a module. It is possible to build single files that are part of a module.
This works equally well for the kernel, a module, and even for This works equally well for the kernel, a module, and even for
external modules. external modules.
Example (The module foo.ko, consist of bar.o and baz.o): Example (The module foo.ko, consist of bar.o and baz.o)::
make -C $KDIR M=$PWD bar.lst make -C $KDIR M=$PWD bar.lst
make -C $KDIR M=$PWD baz.o make -C $KDIR M=$PWD baz.o
make -C $KDIR M=$PWD foo.ko make -C $KDIR M=$PWD foo.ko
make -C $KDIR M=$PWD ./ make -C $KDIR M=$PWD ./
=== 3. Creating a Kbuild File for an External Module 3. Creating a Kbuild File for an External Module
================================================
In the last section we saw the command to build a module for the In the last section we saw the command to build a module for the
running kernel. The module is not actually built, however, because a running kernel. The module is not actually built, however, because a
build file is required. Contained in this file will be the name of build file is required. Contained in this file will be the name of
the module(s) being built, along with the list of requisite source the module(s) being built, along with the list of requisite source
files. The file may be as simple as a single line: files. The file may be as simple as a single line::
obj-m := <module_name>.o obj-m := <module_name>.o
...@@ -157,15 +167,15 @@ The kbuild system will build <module_name>.o from <module_name>.c, ...@@ -157,15 +167,15 @@ The kbuild system will build <module_name>.o from <module_name>.c,
and, after linking, will result in the kernel module <module_name>.ko. and, after linking, will result in the kernel module <module_name>.ko.
The above line can be put in either a "Kbuild" file or a "Makefile." The above line can be put in either a "Kbuild" file or a "Makefile."
When the module is built from multiple sources, an additional line is When the module is built from multiple sources, an additional line is
needed listing the files: needed listing the files::
<module_name>-y := <src1>.o <src2>.o ... <module_name>-y := <src1>.o <src2>.o ...
NOTE: Further documentation describing the syntax used by kbuild is NOTE: Further documentation describing the syntax used by kbuild is
located in Documentation/kbuild/makefiles.txt. located in Documentation/kbuild/makefiles.rst.
The examples below demonstrate how to create a build file for the The examples below demonstrate how to create a build file for the
module 8123.ko, which is built from the following files: module 8123.ko, which is built from the following files::
8123_if.c 8123_if.c
8123_if.h 8123_if.h
...@@ -181,7 +191,8 @@ module 8123.ko, which is built from the following files: ...@@ -181,7 +191,8 @@ module 8123.ko, which is built from the following files:
but should be filtered out from kbuild due to possible name but should be filtered out from kbuild due to possible name
clashes. clashes.
Example 1: Example 1::
--> filename: Makefile --> filename: Makefile
ifneq ($(KERNELRELEASE),) ifneq ($(KERNELRELEASE),)
# kbuild part of makefile # kbuild part of makefile
...@@ -209,14 +220,16 @@ module 8123.ko, which is built from the following files: ...@@ -209,14 +220,16 @@ module 8123.ko, which is built from the following files:
line; the second pass is by the kbuild system, which is line; the second pass is by the kbuild system, which is
initiated by the parameterized "make" in the default target. initiated by the parameterized "make" in the default target.
--- 3.2 Separate Kbuild File and Makefile 3.2 Separate Kbuild File and Makefile
-------------------------------------
In newer versions of the kernel, kbuild will first look for a In newer versions of the kernel, kbuild will first look for a
file named "Kbuild," and only if that is not found, will it file named "Kbuild," and only if that is not found, will it
then look for a makefile. Utilizing a "Kbuild" file allows us then look for a makefile. Utilizing a "Kbuild" file allows us
to split up the makefile from example 1 into two files: to split up the makefile from example 1 into two files:
Example 2: Example 2::
--> filename: Kbuild --> filename: Kbuild
obj-m := 8123.o obj-m := 8123.o
8123-y := 8123_if.o 8123_pci.o 8123_bin.o 8123-y := 8123_if.o 8123_pci.o 8123_bin.o
...@@ -238,7 +251,8 @@ module 8123.ko, which is built from the following files: ...@@ -238,7 +251,8 @@ module 8123.ko, which is built from the following files:
The next example shows a backward compatible version. The next example shows a backward compatible version.
Example 3: Example 3::
--> filename: Kbuild --> filename: Kbuild
obj-m := 8123.o obj-m := 8123.o
8123-y := 8123_if.o 8123_pci.o 8123_bin.o 8123-y := 8123_if.o 8123_pci.o 8123_bin.o
...@@ -266,7 +280,8 @@ module 8123.ko, which is built from the following files: ...@@ -266,7 +280,8 @@ module 8123.ko, which is built from the following files:
makefiles, to be used when the "make" and kbuild parts are makefiles, to be used when the "make" and kbuild parts are
split into separate files. split into separate files.
--- 3.3 Binary Blobs 3.3 Binary Blobs
----------------
Some external modules need to include an object file as a blob. Some external modules need to include an object file as a blob.
kbuild has support for this, but requires the blob file to be kbuild has support for this, but requires the blob file to be
...@@ -277,7 +292,7 @@ module 8123.ko, which is built from the following files: ...@@ -277,7 +292,7 @@ module 8123.ko, which is built from the following files:
Throughout this section, 8123_bin.o_shipped has been used to Throughout this section, 8123_bin.o_shipped has been used to
build the kernel module 8123.ko; it has been included as build the kernel module 8123.ko; it has been included as
8123_bin.o. 8123_bin.o::
8123-y := 8123_if.o 8123_pci.o 8123_bin.o 8123-y := 8123_if.o 8123_pci.o 8123_bin.o
...@@ -285,11 +300,12 @@ module 8123.ko, which is built from the following files: ...@@ -285,11 +300,12 @@ module 8123.ko, which is built from the following files:
files and the binary file, kbuild will pick up different rules files and the binary file, kbuild will pick up different rules
when creating the object file for the module. when creating the object file for the module.
--- 3.4 Building Multiple Modules 3.4 Building Multiple Modules
=============================
kbuild supports building multiple modules with a single build kbuild supports building multiple modules with a single build
file. For example, if you wanted to build two modules, foo.ko file. For example, if you wanted to build two modules, foo.ko
and bar.ko, the kbuild lines would be: and bar.ko, the kbuild lines would be::
obj-m := foo.o bar.o obj-m := foo.o bar.o
foo-y := <foo_srcs> foo-y := <foo_srcs>
...@@ -298,7 +314,8 @@ module 8123.ko, which is built from the following files: ...@@ -298,7 +314,8 @@ module 8123.ko, which is built from the following files:
It is that simple! It is that simple!
=== 4. Include Files 4. Include Files
================
Within the kernel, header files are kept in standard locations Within the kernel, header files are kept in standard locations
according to the following rule: according to the following rule:
...@@ -310,22 +327,25 @@ according to the following rule: ...@@ -310,22 +327,25 @@ according to the following rule:
of the kernel that are located in different directories, then of the kernel that are located in different directories, then
the file is placed in include/linux/. the file is placed in include/linux/.
NOTE: There are two notable exceptions to this rule: larger NOTE:
There are two notable exceptions to this rule: larger
subsystems have their own directory under include/, such as subsystems have their own directory under include/, such as
include/scsi; and architecture specific headers are located include/scsi; and architecture specific headers are located
under arch/$(ARCH)/include/. under arch/$(ARCH)/include/.
--- 4.1 Kernel Includes 4.1 Kernel Includes
-------------------
To include a header file located under include/linux/, simply To include a header file located under include/linux/, simply
use: use::
#include <linux/module.h> #include <linux/module.h>
kbuild will add options to "gcc" so the relevant directories kbuild will add options to "gcc" so the relevant directories
are searched. are searched.
--- 4.2 Single Subdirectory 4.2 Single Subdirectory
-----------------------
External modules tend to place header files in a separate External modules tend to place header files in a separate
include/ directory where their source is located, although this include/ directory where their source is located, although this
...@@ -334,7 +354,7 @@ according to the following rule: ...@@ -334,7 +354,7 @@ according to the following rule:
Using the example from section 3, if we moved 8123_if.h to a Using the example from section 3, if we moved 8123_if.h to a
subdirectory named include, the resulting kbuild file would subdirectory named include, the resulting kbuild file would
look like: look like::
--> filename: Kbuild --> filename: Kbuild
obj-m := 8123.o obj-m := 8123.o
...@@ -346,10 +366,11 @@ according to the following rule: ...@@ -346,10 +366,11 @@ according to the following rule:
the path. This is a limitation of kbuild: there must be no the path. This is a limitation of kbuild: there must be no
space present. space present.
--- 4.3 Several Subdirectories 4.3 Several Subdirectories
--------------------------
kbuild can handle files that are spread over several directories. kbuild can handle files that are spread over several directories.
Consider the following example: Consider the following example::
. .
|__ src |__ src
...@@ -362,7 +383,7 @@ according to the following rule: ...@@ -362,7 +383,7 @@ according to the following rule:
|__ complex.h |__ complex.h
To build the module complex.ko, we then need the following To build the module complex.ko, we then need the following
kbuild file: kbuild file::
--> filename: Kbuild --> filename: Kbuild
obj-m := complex.o obj-m := complex.o
...@@ -385,7 +406,8 @@ according to the following rule: ...@@ -385,7 +406,8 @@ according to the following rule:
file is located. file is located.
=== 5. Module Installation 5. Module Installation
======================
Modules which are included in the kernel are installed in the Modules which are included in the kernel are installed in the
directory: directory:
...@@ -396,11 +418,12 @@ And external modules are installed in: ...@@ -396,11 +418,12 @@ And external modules are installed in:
/lib/modules/$(KERNELRELEASE)/extra/ /lib/modules/$(KERNELRELEASE)/extra/
--- 5.1 INSTALL_MOD_PATH 5.1 INSTALL_MOD_PATH
--------------------
Above are the default directories but as always some level of Above are the default directories but as always some level of
customization is possible. A prefix can be added to the customization is possible. A prefix can be added to the
installation path using the variable INSTALL_MOD_PATH: installation path using the variable INSTALL_MOD_PATH::
$ make INSTALL_MOD_PATH=/frodo modules_install $ make INSTALL_MOD_PATH=/frodo modules_install
=> Install dir: /frodo/lib/modules/$(KERNELRELEASE)/kernel/ => Install dir: /frodo/lib/modules/$(KERNELRELEASE)/kernel/
...@@ -410,20 +433,22 @@ And external modules are installed in: ...@@ -410,20 +433,22 @@ And external modules are installed in:
calling "make." This has effect when installing both in-tree calling "make." This has effect when installing both in-tree
and out-of-tree modules. and out-of-tree modules.
--- 5.2 INSTALL_MOD_DIR 5.2 INSTALL_MOD_DIR
-------------------
External modules are by default installed to a directory under External modules are by default installed to a directory under
/lib/modules/$(KERNELRELEASE)/extra/, but you may wish to /lib/modules/$(KERNELRELEASE)/extra/, but you may wish to
locate modules for a specific functionality in a separate locate modules for a specific functionality in a separate
directory. For this purpose, use INSTALL_MOD_DIR to specify an directory. For this purpose, use INSTALL_MOD_DIR to specify an
alternative name to "extra." alternative name to "extra."::
$ make INSTALL_MOD_DIR=gandalf -C $KDIR \ $ make INSTALL_MOD_DIR=gandalf -C $KDIR \
M=$PWD modules_install M=$PWD modules_install
=> Install dir: /lib/modules/$(KERNELRELEASE)/gandalf/ => Install dir: /lib/modules/$(KERNELRELEASE)/gandalf/
=== 6. Module Versioning 6. Module Versioning
====================
Module versioning is enabled by the CONFIG_MODVERSIONS tag, and is used Module versioning is enabled by the CONFIG_MODVERSIONS tag, and is used
as a simple ABI consistency check. A CRC value of the full prototype as a simple ABI consistency check. A CRC value of the full prototype
...@@ -435,14 +460,16 @@ module. ...@@ -435,14 +460,16 @@ module.
Module.symvers contains a list of all exported symbols from a kernel Module.symvers contains a list of all exported symbols from a kernel
build. build.
--- 6.1 Symbols From the Kernel (vmlinux + modules) 6.1 Symbols From the Kernel (vmlinux + modules)
-----------------------------------------------
During a kernel build, a file named Module.symvers will be During a kernel build, a file named Module.symvers will be
generated. Module.symvers contains all exported symbols from generated. Module.symvers contains all exported symbols from
the kernel and compiled modules. For each symbol, the the kernel and compiled modules. For each symbol, the
corresponding CRC value is also stored. corresponding CRC value is also stored.
The syntax of the Module.symvers file is: The syntax of the Module.symvers file is::
<CRC> <Symbol> <module> <CRC> <Symbol> <module>
0x2d036834 scsi_remove_host drivers/scsi/scsi_mod 0x2d036834 scsi_remove_host drivers/scsi/scsi_mod
...@@ -451,10 +478,12 @@ build. ...@@ -451,10 +478,12 @@ build.
would read 0x00000000. would read 0x00000000.
Module.symvers serves two purposes: Module.symvers serves two purposes:
1) It lists all exported symbols from vmlinux and all modules. 1) It lists all exported symbols from vmlinux and all modules.
2) It lists the CRC if CONFIG_MODVERSIONS is enabled. 2) It lists the CRC if CONFIG_MODVERSIONS is enabled.
--- 6.2 Symbols and External Modules 6.2 Symbols and External Modules
--------------------------------
When building an external module, the build system needs access When building an external module, the build system needs access
to the symbols from the kernel to check if all external symbols to the symbols from the kernel to check if all external symbols
...@@ -481,17 +510,17 @@ build. ...@@ -481,17 +510,17 @@ build.
foo.ko needs symbols from bar.ko, you can use a foo.ko needs symbols from bar.ko, you can use a
common top-level kbuild file so both modules are common top-level kbuild file so both modules are
compiled in the same build. Consider the following compiled in the same build. Consider the following
directory layout: directory layout::
./foo/ <= contains foo.ko ./foo/ <= contains foo.ko
./bar/ <= contains bar.ko ./bar/ <= contains bar.ko
The top-level kbuild file would then look like: The top-level kbuild file would then look like::
#./Kbuild (or ./Makefile): #./Kbuild (or ./Makefile):
obj-y := foo/ bar/ obj-y := foo/ bar/
And executing And executing::
$ make -C $KDIR M=$PWD $ make -C $KDIR M=$PWD
...@@ -518,14 +547,16 @@ build. ...@@ -518,14 +547,16 @@ build.
initialization of its symbol tables. initialization of its symbol tables.
=== 7. Tips & Tricks 7. Tips & Tricks
================
--- 7.1 Testing for CONFIG_FOO_BAR 7.1 Testing for CONFIG_FOO_BAR
------------------------------
Modules often need to check for certain CONFIG_ options to Modules often need to check for certain `CONFIG_` options to
decide if a specific feature is included in the module. In decide if a specific feature is included in the module. In
kbuild this is done by referencing the CONFIG_ variable kbuild this is done by referencing the `CONFIG_` variable
directly. directly::
#fs/ext2/Makefile #fs/ext2/Makefile
obj-$(CONFIG_EXT2_FS) += ext2.o obj-$(CONFIG_EXT2_FS) += ext2.o
...@@ -534,8 +565,7 @@ build. ...@@ -534,8 +565,7 @@ build.
ext2-$(CONFIG_EXT2_FS_XATTR) += xattr.o ext2-$(CONFIG_EXT2_FS_XATTR) += xattr.o
External modules have traditionally used "grep" to check for External modules have traditionally used "grep" to check for
specific CONFIG_ settings directly in .config. This usage is specific `CONFIG_` settings directly in .config. This usage is
broken. As introduced before, external modules should use broken. As introduced before, external modules should use
kbuild for building and can therefore use the same methods as kbuild for building and can therefore use the same methods as
in-tree modules when testing for CONFIG_ definitions. in-tree modules when testing for `CONFIG_` definitions.
Documentation/kernel-hacking/hacking.rst
View file @ cd238eff
...@@ -718,7 +718,7 @@ make a neat patch, there's administrative work to be done: ...@@ -718,7 +718,7 @@ make a neat patch, there's administrative work to be done:
- Usually you want a configuration option for your kernel hack. Edit - Usually you want a configuration option for your kernel hack. Edit
``Kconfig`` in the appropriate directory. The Config language is ``Kconfig`` in the appropriate directory. The Config language is
simple to use by cut and paste, and there's complete documentation in simple to use by cut and paste, and there's complete documentation in
``Documentation/kbuild/kconfig-language.txt``. ``Documentation/kbuild/kconfig-language.rst``.
In your description of the option, make sure you address both the In your description of the option, make sure you address both the
expert user and the user who knows nothing about your feature. expert user and the user who knows nothing about your feature.
...@@ -728,7 +728,7 @@ make a neat patch, there's administrative work to be done: ...@@ -728,7 +728,7 @@ make a neat patch, there's administrative work to be done:
- Edit the ``Makefile``: the CONFIG variables are exported here so you - Edit the ``Makefile``: the CONFIG variables are exported here so you
can usually just add a "obj-$(CONFIG_xxx) += xxx.o" line. The syntax can usually just add a "obj-$(CONFIG_xxx) += xxx.o" line. The syntax
is documented in ``Documentation/kbuild/makefiles.txt``. is documented in ``Documentation/kbuild/makefiles.rst``.
- Put yourself in ``CREDITS`` if you've done something noteworthy, - Put yourself in ``CREDITS`` if you've done something noteworthy,
usually beyond a single file (your name should be at the top of the usually beyond a single file (your name should be at the top of the
......
Documentation/process/coding-style.rst
View file @ cd238eff
...@@ -686,7 +686,7 @@ filesystems) should advertise this prominently in their prompt string:: ...@@ -686,7 +686,7 @@ filesystems) should advertise this prominently in their prompt string::
... ...
For full documentation on the configuration files, see the file For full documentation on the configuration files, see the file
Documentation/kbuild/kconfig-language.txt. Documentation/kbuild/kconfig-language.rst.
11) Data structures 11) Data structures
......
Documentation/process/submit-checklist.rst
View file @ cd238eff
...@@ -39,7 +39,7 @@ and elsewhere regarding submitting Linux kernel patches. ...@@ -39,7 +39,7 @@ and elsewhere regarding submitting Linux kernel patches.
6) Any new or modified ``CONFIG`` options do not muck up the config menu and 6) Any new or modified ``CONFIG`` options do not muck up the config menu and
default to off unless they meet the exception criteria documented in default to off unless they meet the exception criteria documented in
``Documentation/kbuild/kconfig-language.txt`` Menu attributes: default value. ``Documentation/kbuild/kconfig-language.rst`` Menu attributes: default value.
7) All new ``Kconfig`` options have help text. 7) All new ``Kconfig`` options have help text.
......
Documentation/translations/it_IT/kernel-hacking/hacking.rst
View file @ cd238eff
...@@ -755,7 +755,7 @@ anche per avere patch pulite, c'è del lavoro amministrativo da fare: ...@@ -755,7 +755,7 @@ anche per avere patch pulite, c'è del lavoro amministrativo da fare:
- Solitamente vorrete un'opzione di configurazione per la vostra modifica - Solitamente vorrete un'opzione di configurazione per la vostra modifica
al kernel. Modificate ``Kconfig`` nella cartella giusta. Il linguaggio al kernel. Modificate ``Kconfig`` nella cartella giusta. Il linguaggio
Config è facile con copia ed incolla, e c'è una completa documentazione Config è facile con copia ed incolla, e c'è una completa documentazione
nel file ``Documentation/kbuild/kconfig-language.txt``. nel file ``Documentation/kbuild/kconfig-language.rst``.
Nella descrizione della vostra opzione, assicuratevi di parlare sia agli Nella descrizione della vostra opzione, assicuratevi di parlare sia agli
utenti esperti sia agli utente che non sanno nulla del vostro lavoro. utenti esperti sia agli utente che non sanno nulla del vostro lavoro.
...@@ -767,7 +767,7 @@ anche per avere patch pulite, c'è del lavoro amministrativo da fare: ...@@ -767,7 +767,7 @@ anche per avere patch pulite, c'è del lavoro amministrativo da fare:
- Modificate il file ``Makefile``: le variabili CONFIG sono esportate qui, - Modificate il file ``Makefile``: le variabili CONFIG sono esportate qui,
quindi potete solitamente aggiungere una riga come la seguete quindi potete solitamente aggiungere una riga come la seguete
"obj-$(CONFIG_xxx) += xxx.o". La sintassi è documentata nel file "obj-$(CONFIG_xxx) += xxx.o". La sintassi è documentata nel file
``Documentation/kbuild/makefiles.txt``. ``Documentation/kbuild/makefiles.rst``.
- Aggiungete voi stessi in ``CREDITS`` se avete fatto qualcosa di notevole, - Aggiungete voi stessi in ``CREDITS`` se avete fatto qualcosa di notevole,
solitamente qualcosa che supera il singolo file (comunque il vostro nome solitamente qualcosa che supera il singolo file (comunque il vostro nome
......
Documentation/translations/it_IT/process/coding-style.rst
View file @ cd238eff
...@@ -696,7 +696,7 @@ nella stringa di titolo:: ...@@ -696,7 +696,7 @@ nella stringa di titolo::
... ...
Per la documentazione completa sui file di configurazione, consultate Per la documentazione completa sui file di configurazione, consultate
il documento Documentation/kbuild/kconfig-language.txt il documento Documentation/kbuild/kconfig-language.rst
11) Strutture dati 11) Strutture dati
......
Documentation/translations/it_IT/process/submit-checklist.rst
View file @ cd238eff
...@@ -43,7 +43,7 @@ sottomissione delle patch, in particolare ...@@ -43,7 +43,7 @@ sottomissione delle patch, in particolare
6) Le opzioni ``CONFIG``, nuove o modificate, non scombussolano il menu 6) Le opzioni ``CONFIG``, nuove o modificate, non scombussolano il menu
di configurazione e sono preimpostate come disabilitate a meno che non di configurazione e sono preimpostate come disabilitate a meno che non
soddisfino i criteri descritti in ``Documentation/kbuild/kconfig-language.txt`` soddisfino i criteri descritti in ``Documentation/kbuild/kconfig-language.rst``
alla punto "Voci di menu: valori predefiniti". alla punto "Voci di menu: valori predefiniti".
7) Tutte le nuove opzioni ``Kconfig`` hanno un messaggio di aiuto. 7) Tutte le nuove opzioni ``Kconfig`` hanno un messaggio di aiuto.
......
Documentation/translations/zh_CN/process/coding-style.rst
View file @ cd238eff
...@@ -599,7 +599,7 @@ Documentation/doc-guide/ 和 scripts/kernel-doc 以获得详细信息。 ...@@ -599,7 +599,7 @@ Documentation/doc-guide/ 和 scripts/kernel-doc 以获得详细信息。
depends on ADFS_FS depends on ADFS_FS
... ...
要查看配置文件的完整文档，请看 Documentation/kbuild/kconfig-language.txt。 要查看配置文件的完整文档，请看 Documentation/kbuild/kconfig-language.rst。
11) 数据结构 11) 数据结构
......
Documentation/translations/zh_CN/process/submit-checklist.rst
View file @ cd238eff
...@@ -38,7 +38,7 @@ Linux内核补丁提交清单 ...@@ -38,7 +38,7 @@ Linux内核补丁提交清单
违规行为。 违规行为。
6) 任何新的或修改过的 ``CONFIG`` 选项都不会弄脏配置菜单，并默认为关闭，除非 6) 任何新的或修改过的 ``CONFIG`` 选项都不会弄脏配置菜单，并默认为关闭，除非
它们符合 ``Documentation/kbuild/kconfig-language.txt`` 中记录的异常条件, 它们符合 ``Documentation/kbuild/kconfig-language.rst`` 中记录的异常条件,
菜单属性：默认值. 菜单属性：默认值.
7) 所有新的 ``kconfig`` 选项都有帮助文本。 7) 所有新的 ``kconfig`` 选项都有帮助文本。
......
Kconfig
View file @ cd238eff
# SPDX-License-Identifier: GPL-2.0 # SPDX-License-Identifier: GPL-2.0
# #
# For a description of the syntax of this configuration file, # For a description of the syntax of this configuration file,
# see Documentation/kbuild/kconfig-language.txt. # see Documentation/kbuild/kconfig-language.rst.
# #
mainmenu "Linux/$(ARCH) $(KERNELVERSION) Kernel Configuration" mainmenu "Linux/$(ARCH) $(KERNELVERSION) Kernel Configuration"
......
arch/arc/plat-eznps/Kconfig
View file @ cd238eff
# SPDX-License-Identifier: GPL-2.0 # SPDX-License-Identifier: GPL-2.0
# #
# For a description of the syntax of this configuration file, # For a description of the syntax of this configuration file,
# see Documentation/kbuild/kconfig-language.txt. # see Documentation/kbuild/kconfig-language.rst.
# #
menuconfig ARC_PLAT_EZNPS menuconfig ARC_PLAT_EZNPS
......
arch/c6x/Kconfig
View file @ cd238eff
# SPDX-License-Identifier: GPL-2.0 # SPDX-License-Identifier: GPL-2.0
# #
# For a description of the syntax of this configuration file, # For a description of the syntax of this configuration file,
# see Documentation/kbuild/kconfig-language.txt. # see Documentation/kbuild/kconfig-language.rst.
# #
config C6X config C6X
......
arch/microblaze/Kconfig.debug
View file @ cd238eff
# SPDX-License-Identifier: GPL-2.0-only # SPDX-License-Identifier: GPL-2.0-only
# For a description of the syntax of this configuration file, # For a description of the syntax of this configuration file,
# see Documentation/kbuild/kconfig-language.txt. # see Documentation/kbuild/kconfig-language.rst.
config TRACE_IRQFLAGS_SUPPORT config TRACE_IRQFLAGS_SUPPORT
def_bool y def_bool y
arch/microblaze/Kconfig.platform
View file @ cd238eff
# SPDX-License-Identifier: GPL-2.0-only # SPDX-License-Identifier: GPL-2.0-only
# For a description of the syntax of this configuration file, # For a description of the syntax of this configuration file,
# see Documentation/kbuild/kconfig-language.txt. # see Documentation/kbuild/kconfig-language.rst.
# #
# Platform selection Kconfig menu for MicroBlaze targets # Platform selection Kconfig menu for MicroBlaze targets
# #
......
arch/nds32/Kconfig
View file @ cd238eff
# SPDX-License-Identifier: GPL-2.0-only # SPDX-License-Identifier: GPL-2.0-only
# #
# For a description of the syntax of this configuration file, # For a description of the syntax of this configuration file,
# see Documentation/kbuild/kconfig-language.txt. # see Documentation/kbuild/kconfig-language.rst.
# #
config NDS32 config NDS32
......
arch/openrisc/Kconfig
View file @ cd238eff
# SPDX-License-Identifier: GPL-2.0 # SPDX-License-Identifier: GPL-2.0
# #
# For a description of the syntax of this configuration file, # For a description of the syntax of this configuration file,
# see Documentation/kbuild/kconfig-language.txt. # see Documentation/kbuild/kconfig-language.rst.
# #
config OPENRISC config OPENRISC
......
arch/powerpc/sysdev/Kconfig
View file @ cd238eff
# SPDX-License-Identifier: GPL-2.0 # SPDX-License-Identifier: GPL-2.0
# For a description of the syntax of this configuration file, # For a description of the syntax of this configuration file,
# see Documentation/kbuild/kconfig-language.txt. # see Documentation/kbuild/kconfig-language.rst.
# #
config PPC4xx_PCI_EXPRESS config PPC4xx_PCI_EXPRESS
......
arch/riscv/Kconfig
View file @ cd238eff
# SPDX-License-Identifier: GPL-2.0-only # SPDX-License-Identifier: GPL-2.0-only
# #
# For a description of the syntax of this configuration file, # For a description of the syntax of this configuration file,
# see Documentation/kbuild/kconfig-language.txt. # see Documentation/kbuild/kconfig-language.rst.
# #
config 64BIT config 64BIT
......
drivers/auxdisplay/Kconfig
View file @ cd238eff
# SPDX-License-Identifier: GPL-2.0 # SPDX-License-Identifier: GPL-2.0
# #
# For a description of the syntax of this configuration file, # For a description of the syntax of this configuration file,
# see Documentation/kbuild/kconfig-language.txt. # see Documentation/kbuild/kconfig-language.rst.
# #
# Auxiliary display drivers configuration. # Auxiliary display drivers configuration.
# #
......
drivers/firmware/Kconfig
View file @ cd238eff
# SPDX-License-Identifier: GPL-2.0-only # SPDX-License-Identifier: GPL-2.0-only
# #
# For a description of the syntax of this configuration file, # For a description of the syntax of this configuration file,
# see Documentation/kbuild/kconfig-language.txt. # see Documentation/kbuild/kconfig-language.rst.
# #
menu "Firmware Drivers" menu "Firmware Drivers"
......
drivers/mtd/devices/Kconfig
View file @ cd238eff
...@@ -48,7 +48,7 @@ config MTD_MS02NV ...@@ -48,7 +48,7 @@ config MTD_MS02NV
If you want to compile this driver as a module ( = code which can be If you want to compile this driver as a module ( = code which can be
inserted in and removed from the running kernel whenever you want), inserted in and removed from the running kernel whenever you want),
say M here and read <file:Documentation/kbuild/modules.txt>. say M here and read <file:Documentation/kbuild/modules.rst>.
The module will be called ms02-nv. The module will be called ms02-nv.
config MTD_DATAFLASH config MTD_DATAFLASH
......
drivers/net/ethernet/smsc/Kconfig
View file @ cd238eff
...@@ -49,7 +49,7 @@ config SMC91X ...@@ -49,7 +49,7 @@ config SMC91X
This driver is also available as a module ( = code which can be This driver is also available as a module ( = code which can be
inserted in and removed from the running kernel whenever you want). inserted in and removed from the running kernel whenever you want).
The module will be called smc91x. If you want to compile it as a The module will be called smc91x. If you want to compile it as a
module, say M here and read <file:Documentation/kbuild/modules.txt>. module, say M here and read <file:Documentation/kbuild/modules.rst>.
config PCMCIA_SMC91C92 config PCMCIA_SMC91C92
tristate "SMC 91Cxx PCMCIA support" tristate "SMC 91Cxx PCMCIA support"
...@@ -86,7 +86,7 @@ config SMC911X ...@@ -86,7 +86,7 @@ config SMC911X
This driver is also available as a module. The module will be This driver is also available as a module. The module will be
called smc911x. If you want to compile it as a module, say M called smc911x. If you want to compile it as a module, say M
here and read <file:Documentation/kbuild/modules.txt> here and read <file:Documentation/kbuild/modules.rst>
config SMSC911X config SMSC911X
tristate "SMSC LAN911x/LAN921x families embedded ethernet support" tristate "SMSC LAN911x/LAN921x families embedded ethernet support"
...@@ -121,6 +121,6 @@ config SMSC9420 ...@@ -121,6 +121,6 @@ config SMSC9420
This driver is also available as a module. The module will be This driver is also available as a module. The module will be
called smsc9420. If you want to compile it as a module, say M called smsc9420. If you want to compile it as a module, say M
here and read <file:Documentation/kbuild/modules.txt> here and read <file:Documentation/kbuild/modules.rst>
endif # NET_VENDOR_SMSC endif # NET_VENDOR_SMSC
drivers/net/wireless/intel/iwlegacy/Kconfig
View file @ cd238eff
...@@ -32,7 +32,7 @@ config IWL4965 ...@@ -32,7 +32,7 @@ config IWL4965
If you want to compile the driver as a module ( = code which can be If you want to compile the driver as a module ( = code which can be
inserted in and removed from the running kernel whenever you want), inserted in and removed from the running kernel whenever you want),
say M here and read <file:Documentation/kbuild/modules.txt>. The say M here and read <file:Documentation/kbuild/modules.rst>. The
module will be called iwl4965. module will be called iwl4965.
config IWL3945 config IWL3945
...@@ -58,7 +58,7 @@ config IWL3945 ...@@ -58,7 +58,7 @@ config IWL3945
If you want to compile the driver as a module ( = code which can be If you want to compile the driver as a module ( = code which can be
inserted in and removed from the running kernel whenever you want), inserted in and removed from the running kernel whenever you want),
say M here and read <file:Documentation/kbuild/modules.txt>. The say M here and read <file:Documentation/kbuild/modules.rst>. The
module will be called iwl3945. module will be called iwl3945.
menu "iwl3945 / iwl4965 Debugging Options" menu "iwl3945 / iwl4965 Debugging Options"
......
drivers/net/wireless/intel/iwlwifi/Kconfig
View file @ cd238eff
...@@ -40,7 +40,7 @@ config IWLWIFI ...@@ -40,7 +40,7 @@ config IWLWIFI
If you want to compile the driver as a module ( = code which can be If you want to compile the driver as a module ( = code which can be
inserted in and removed from the running kernel whenever you want), inserted in and removed from the running kernel whenever you want),
say M here and read <file:Documentation/kbuild/modules.txt>. The say M here and read <file:Documentation/kbuild/modules.rst>. The
module will be called iwlwifi. module will be called iwlwifi.
if IWLWIFI if IWLWIFI
......
drivers/parport/Kconfig
View file @ cd238eff
# SPDX-License-Identifier: GPL-2.0-only # SPDX-License-Identifier: GPL-2.0-only
# #
# For a description of the syntax of this configuration file, # For a description of the syntax of this configuration file,
# see Documentation/kbuild/kconfig-language.txt. # see Documentation/kbuild/kconfig-language.rst.
# #
# Parport configuration. # Parport configuration.
# #
......
drivers/scsi/Kconfig
View file @ cd238eff
...@@ -183,7 +183,7 @@ config CHR_DEV_SCH ...@@ -183,7 +183,7 @@ config CHR_DEV_SCH
If you want to compile this as a module ( = code which can be If you want to compile this as a module ( = code which can be
inserted in and removed from the running kernel whenever you want), inserted in and removed from the running kernel whenever you want),
say M here and read <file:Documentation/kbuild/modules.txt> and say M here and read <file:Documentation/kbuild/modules.rst> and
<file:Documentation/scsi/scsi.txt>. The module will be called ch.o. <file:Documentation/scsi/scsi.txt>. The module will be called ch.o.
If unsure, say N. If unsure, say N.
...@@ -1474,7 +1474,7 @@ config ZFCP ...@@ -1474,7 +1474,7 @@ config ZFCP
This driver is also available as a module. This module will be This driver is also available as a module. This module will be
called zfcp. If you want to compile it as a module, say M here called zfcp. If you want to compile it as a module, say M here
and read <file:Documentation/kbuild/modules.txt>. and read <file:Documentation/kbuild/modules.rst>.
config SCSI_PMCRAID config SCSI_PMCRAID
tristate "PMC SIERRA Linux MaxRAID adapter support" tristate "PMC SIERRA Linux MaxRAID adapter support"
......
drivers/staging/sm750fb/Kconfig
View file @ cd238eff
...@@ -12,4 +12,4 @@ config FB_SM750 ...@@ -12,4 +12,4 @@ config FB_SM750
This driver is also available as a module. The module will be This driver is also available as a module. The module will be
called sm750fb. If you want to compile it as a module, say M called sm750fb. If you want to compile it as a module, say M
here and read <file:Documentation/kbuild/modules.txt>. here and read <file:Documentation/kbuild/modules.rst>.
drivers/usb/misc/Kconfig
View file @ cd238eff
...@@ -16,7 +16,7 @@ config USB_EMI62 ...@@ -16,7 +16,7 @@ config USB_EMI62
This code is also available as a module ( = code which can be This code is also available as a module ( = code which can be
inserted in and removed from the running kernel whenever you want). inserted in and removed from the running kernel whenever you want).
The module will be called audio. If you want to compile it as a The module will be called audio. If you want to compile it as a
module, say M here and read <file:Documentation/kbuild/modules.txt>. module, say M here and read <file:Documentation/kbuild/modules.rst>.
config USB_EMI26 config USB_EMI26
tristate "EMI 2|6 USB Audio interface support" tristate "EMI 2|6 USB Audio interface support"
...@@ -67,7 +67,7 @@ config USB_LEGOTOWER ...@@ -67,7 +67,7 @@ config USB_LEGOTOWER
inserted in and removed from the running kernel whenever you want). inserted in and removed from the running kernel whenever you want).
The module will be called legousbtower. If you want to compile it as The module will be called legousbtower. If you want to compile it as
a module, say M here and read a module, say M here and read
<file:Documentation/kbuild/modules.txt>. <file:Documentation/kbuild/modules.rst>.
config USB_LCD config USB_LCD
tristate "USB LCD driver support" tristate "USB LCD driver support"
......
drivers/video/fbdev/Kconfig
View file @ cd238eff
...@@ -289,7 +289,7 @@ config FB_ARMCLCD ...@@ -289,7 +289,7 @@ config FB_ARMCLCD
If you want to compile this as a module (=code which can be If you want to compile this as a module (=code which can be
inserted into and removed from the running kernel), say M inserted into and removed from the running kernel), say M
here and read <file:Documentation/kbuild/modules.txt>. The module here and read <file:Documentation/kbuild/modules.rst>. The module
will be called amba-clcd. will be called amba-clcd.
config FB_ACORN config FB_ACORN
...@@ -1752,7 +1752,7 @@ config FB_PXA ...@@ -1752,7 +1752,7 @@ config FB_PXA
This driver is also available as a module ( = code which can be This driver is also available as a module ( = code which can be
inserted and removed from the running kernel whenever you want). The inserted and removed from the running kernel whenever you want). The
module will be called pxafb. If you want to compile it as a module, module will be called pxafb. If you want to compile it as a module,
say M here and read <file:Documentation/kbuild/modules.txt>. say M here and read <file:Documentation/kbuild/modules.rst>.
If unsure, say N. If unsure, say N.
...@@ -1833,7 +1833,7 @@ config FB_W100 ...@@ -1833,7 +1833,7 @@ config FB_W100
This driver is also available as a module ( = code which can be This driver is also available as a module ( = code which can be
inserted and removed from the running kernel whenever you want). The inserted and removed from the running kernel whenever you want). The
module will be called w100fb. If you want to compile it as a module, module will be called w100fb. If you want to compile it as a module,
say M here and read <file:Documentation/kbuild/modules.txt>. say M here and read <file:Documentation/kbuild/modules.rst>.
If unsure, say N. If unsure, say N.
...@@ -1862,7 +1862,7 @@ config FB_TMIO ...@@ -1862,7 +1862,7 @@ config FB_TMIO
This driver is also available as a module ( = code which can be This driver is also available as a module ( = code which can be
inserted and removed from the running kernel whenever you want). The inserted and removed from the running kernel whenever you want). The
module will be called tmiofb. If you want to compile it as a module, module will be called tmiofb. If you want to compile it as a module,
say M here and read <file:Documentation/kbuild/modules.txt>. say M here and read <file:Documentation/kbuild/modules.rst>.
If unsure, say N. If unsure, say N.
...@@ -1908,7 +1908,7 @@ config FB_S3C2410 ...@@ -1908,7 +1908,7 @@ config FB_S3C2410
This driver is also available as a module ( = code which can be This driver is also available as a module ( = code which can be
inserted and removed from the running kernel whenever you want). The inserted and removed from the running kernel whenever you want). The
module will be called s3c2410fb. If you want to compile it as a module, module will be called s3c2410fb. If you want to compile it as a module,
say M here and read <file:Documentation/kbuild/modules.txt>. say M here and read <file:Documentation/kbuild/modules.rst>.
If unsure, say N. If unsure, say N.
config FB_S3C2410_DEBUG config FB_S3C2410_DEBUG
...@@ -1945,7 +1945,7 @@ config FB_SM501 ...@@ -1945,7 +1945,7 @@ config FB_SM501
This driver is also available as a module ( = code which can be This driver is also available as a module ( = code which can be
inserted and removed from the running kernel whenever you want). The inserted and removed from the running kernel whenever you want). The
module will be called sm501fb. If you want to compile it as a module, module will be called sm501fb. If you want to compile it as a module,
say M here and read <file:Documentation/kbuild/modules.txt>. say M here and read <file:Documentation/kbuild/modules.rst>.
If unsure, say N. If unsure, say N.
...@@ -2288,7 +2288,7 @@ config FB_SM712 ...@@ -2288,7 +2288,7 @@ config FB_SM712
This driver is also available as a module. The module will be This driver is also available as a module. The module will be
called sm712fb. If you want to compile it as a module, say M called sm712fb. If you want to compile it as a module, say M
here and read <file:Documentation/kbuild/modules.txt>. here and read <file:Documentation/kbuild/modules.rst>.
source "drivers/video/fbdev/omap/Kconfig" source "drivers/video/fbdev/omap/Kconfig"
source "drivers/video/fbdev/omap2/Kconfig" source "drivers/video/fbdev/omap2/Kconfig"
......
net/bridge/netfilter/Kconfig
View file @ cd238eff
...@@ -114,7 +114,7 @@ config BRIDGE_EBT_LIMIT ...@@ -114,7 +114,7 @@ config BRIDGE_EBT_LIMIT
equivalent of the iptables limit match. equivalent of the iptables limit match.
If you want to compile it as a module, say M here and read If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. If unsure, say `N'. <file:Documentation/kbuild/modules.rst>. If unsure, say `N'.
config BRIDGE_EBT_MARK config BRIDGE_EBT_MARK
tristate "ebt: mark filter support" tristate "ebt: mark filter support"
......
net/ipv4/netfilter/Kconfig
View file @ cd238eff
...@@ -308,7 +308,7 @@ config IP_NF_RAW ...@@ -308,7 +308,7 @@ config IP_NF_RAW
and OUTPUT chains. and OUTPUT chains.
If you want to compile it as a module, say M here and read If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. If unsure, say `N'. <file:Documentation/kbuild/modules.rst>. If unsure, say `N'.
# security table for MAC policy # security table for MAC policy
config IP_NF_SECURITY config IP_NF_SECURITY
......
net/ipv6/netfilter/Kconfig
View file @ cd238eff
...@@ -241,7 +241,7 @@ config IP6_NF_RAW ...@@ -241,7 +241,7 @@ config IP6_NF_RAW
and OUTPUT chains. and OUTPUT chains.
If you want to compile it as a module, say M here and read If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. If unsure, say `N'. <file:Documentation/kbuild/modules.rst>. If unsure, say `N'.
# security table for MAC policy # security table for MAC policy
config IP6_NF_SECURITY config IP6_NF_SECURITY
......
net/netfilter/Kconfig
View file @ cd238eff
...@@ -1056,7 +1056,7 @@ config NETFILTER_XT_TARGET_TRACE ...@@ -1056,7 +1056,7 @@ config NETFILTER_XT_TARGET_TRACE
the tables, chains, rules. the tables, chains, rules.
If you want to compile it as a module, say M here and read If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. If unsure, say `N'. <file:Documentation/kbuild/modules.rst>. If unsure, say `N'.
config NETFILTER_XT_TARGET_SECMARK config NETFILTER_XT_TARGET_SECMARK
tristate '"SECMARK" target support' tristate '"SECMARK" target support'
...@@ -1115,7 +1115,7 @@ config NETFILTER_XT_MATCH_ADDRTYPE ...@@ -1115,7 +1115,7 @@ config NETFILTER_XT_MATCH_ADDRTYPE
eg. UNICAST, LOCAL, BROADCAST, ... eg. UNICAST, LOCAL, BROADCAST, ...
If you want to compile it as a module, say M here and read If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. If unsure, say `N'. <file:Documentation/kbuild/modules.rst>. If unsure, say `N'.
config NETFILTER_XT_MATCH_BPF config NETFILTER_XT_MATCH_BPF
tristate '"bpf" match support' tristate '"bpf" match support'
...@@ -1160,7 +1160,7 @@ config NETFILTER_XT_MATCH_COMMENT ...@@ -1160,7 +1160,7 @@ config NETFILTER_XT_MATCH_COMMENT
comments in your iptables ruleset. comments in your iptables ruleset.
If you want to compile it as a module, say M here and read If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. If unsure, say `N'. <file:Documentation/kbuild/modules.rst>. If unsure, say `N'.
config NETFILTER_XT_MATCH_CONNBYTES config NETFILTER_XT_MATCH_CONNBYTES
tristate '"connbytes" per-connection counter match support' tristate '"connbytes" per-connection counter match support'
...@@ -1171,7 +1171,7 @@ config NETFILTER_XT_MATCH_CONNBYTES ...@@ -1171,7 +1171,7 @@ config NETFILTER_XT_MATCH_CONNBYTES
number of bytes and/or packets for each direction within a connection. number of bytes and/or packets for each direction within a connection.
If you want to compile it as a module, say M here and read If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. If unsure, say `N'. <file:Documentation/kbuild/modules.rst>. If unsure, say `N'.
config NETFILTER_XT_MATCH_CONNLABEL config NETFILTER_XT_MATCH_CONNLABEL
tristate '"connlabel" match support' tristate '"connlabel" match support'
...@@ -1237,7 +1237,7 @@ config NETFILTER_XT_MATCH_DCCP ...@@ -1237,7 +1237,7 @@ config NETFILTER_XT_MATCH_DCCP
and DCCP flags. and DCCP flags.
If you want to compile it as a module, say M here and read If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. If unsure, say `N'. <file:Documentation/kbuild/modules.rst>. If unsure, say `N'.
config NETFILTER_XT_MATCH_DEVGROUP config NETFILTER_XT_MATCH_DEVGROUP
tristate '"devgroup" match support' tristate '"devgroup" match support'
...@@ -1473,7 +1473,7 @@ config NETFILTER_XT_MATCH_QUOTA ...@@ -1473,7 +1473,7 @@ config NETFILTER_XT_MATCH_QUOTA
byte counter. byte counter.
If you want to compile it as a module, say M here and read If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. If unsure, say `N'. <file:Documentation/kbuild/modules.rst>. If unsure, say `N'.
config NETFILTER_XT_MATCH_RATEEST config NETFILTER_XT_MATCH_RATEEST
tristate '"rateest" match support' tristate '"rateest" match support'
...@@ -1497,7 +1497,7 @@ config NETFILTER_XT_MATCH_REALM ...@@ -1497,7 +1497,7 @@ config NETFILTER_XT_MATCH_REALM
in tc world. in tc world.
If you want to compile it as a module, say M here and read If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. If unsure, say `N'. <file:Documentation/kbuild/modules.rst>. If unsure, say `N'.
config NETFILTER_XT_MATCH_RECENT config NETFILTER_XT_MATCH_RECENT
tristate '"recent" match support' tristate '"recent" match support'
...@@ -1519,7 +1519,7 @@ config NETFILTER_XT_MATCH_SCTP ...@@ -1519,7 +1519,7 @@ config NETFILTER_XT_MATCH_SCTP
and SCTP chunk types. and SCTP chunk types.
If you want to compile it as a module, say M here and read If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. If unsure, say `N'. <file:Documentation/kbuild/modules.rst>. If unsure, say `N'.
config NETFILTER_XT_MATCH_SOCKET config NETFILTER_XT_MATCH_SOCKET
tristate '"socket" match support' tristate '"socket" match support'
......
net/tipc/Kconfig
View file @ cd238eff
...@@ -17,7 +17,7 @@ menuconfig TIPC ...@@ -17,7 +17,7 @@ menuconfig TIPC
This protocol support is also available as a module ( = code which This protocol support is also available as a module ( = code which
can be inserted in and removed from the running kernel whenever you can be inserted in and removed from the running kernel whenever you
want). The module will be called tipc. If you want to compile it want). The module will be called tipc. If you want to compile it
as a module, say M here and read <file:Documentation/kbuild/modules.txt>. as a module, say M here and read <file:Documentation/kbuild/modules.rst>.
If in doubt, say N. If in doubt, say N.
......
scripts/Kbuild.include
View file @ cd238eff
...@@ -68,7 +68,7 @@ endef ...@@ -68,7 +68,7 @@ endef
###### ######
# gcc support functions # gcc support functions
# See documentation in Documentation/kbuild/makefiles.txt # See documentation in Documentation/kbuild/makefiles.rst
# cc-cross-prefix # cc-cross-prefix
# Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-) # Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
...@@ -210,7 +210,7 @@ objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o))) ...@@ -210,7 +210,7 @@ objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))
# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies # if_changed_dep - as if_changed, but uses fixdep to reveal dependencies
# including used config symbols # including used config symbols
# if_changed_rule - as if_changed but execute rule instead # if_changed_rule - as if_changed but execute rule instead
# See Documentation/kbuild/makefiles.txt for more info # See Documentation/kbuild/makefiles.rst for more info
ifneq ($(KBUILD_NOCMDDEP),1) ifneq ($(KBUILD_NOCMDDEP),1)
# Check if both arguments are the same including their order. Result is empty # Check if both arguments are the same including their order. Result is empty
......
scripts/Makefile.host
View file @ cd238eff
...@@ -6,7 +6,7 @@ ...@@ -6,7 +6,7 @@
# #
# Both C and C++ are supported, but preferred language is C for such utilities. # Both C and C++ are supported, but preferred language is C for such utilities.
# #
# Sample syntax (see Documentation/kbuild/makefiles.txt for reference) # Sample syntax (see Documentation/kbuild/makefiles.rst for reference)
# hostprogs-y := bin2hex # hostprogs-y := bin2hex
# Will compile bin2hex.c and create an executable named bin2hex # Will compile bin2hex.c and create an executable named bin2hex
# #
......
scripts/kconfig/symbol.c
View file @ cd238eff
...@@ -1114,7 +1114,7 @@ static void sym_check_print_recursive(struct symbol *last_sym) ...@@ -1114,7 +1114,7 @@ static void sym_check_print_recursive(struct symbol *last_sym)
} }
fprintf(stderr, fprintf(stderr,
"For a resolution refer to Documentation/kbuild/kconfig-language.txt\n" "For a resolution refer to Documentation/kbuild/kconfig-language.rst\n"
"subsection \"Kconfig recursive dependency limitations\"\n" "subsection \"Kconfig recursive dependency limitations\"\n"
"\n"); "\n");
......
scripts/kconfig/tests/err_recursive_dep/expected_stderr
View file @ cd238eff
Kconfig:11:error: recursive dependency detected! Kconfig:11:error: recursive dependency detected!
Kconfig:11: symbol B is selected by B Kconfig:11: symbol B is selected by B
For a resolution refer to Documentation/kbuild/kconfig-language.txt For a resolution refer to Documentation/kbuild/kconfig-language.rst
subsection "Kconfig recursive dependency limitations" subsection "Kconfig recursive dependency limitations"
Kconfig:5:error: recursive dependency detected! Kconfig:5:error: recursive dependency detected!
Kconfig:5: symbol A depends on A Kconfig:5: symbol A depends on A
For a resolution refer to Documentation/kbuild/kconfig-language.txt For a resolution refer to Documentation/kbuild/kconfig-language.rst
subsection "Kconfig recursive dependency limitations" subsection "Kconfig recursive dependency limitations"
Kconfig:17:error: recursive dependency detected! Kconfig:17:error: recursive dependency detected!
Kconfig:17: symbol C1 depends on C2 Kconfig:17: symbol C1 depends on C2
Kconfig:21: symbol C2 depends on C1 Kconfig:21: symbol C2 depends on C1
For a resolution refer to Documentation/kbuild/kconfig-language.txt For a resolution refer to Documentation/kbuild/kconfig-language.rst
subsection "Kconfig recursive dependency limitations" subsection "Kconfig recursive dependency limitations"
Kconfig:32:error: recursive dependency detected! Kconfig:32:error: recursive dependency detected!
Kconfig:32: symbol D2 is selected by D1 Kconfig:32: symbol D2 is selected by D1
Kconfig:27: symbol D1 depends on D2 Kconfig:27: symbol D1 depends on D2
For a resolution refer to Documentation/kbuild/kconfig-language.txt For a resolution refer to Documentation/kbuild/kconfig-language.rst
subsection "Kconfig recursive dependency limitations" subsection "Kconfig recursive dependency limitations"
Kconfig:37:error: recursive dependency detected! Kconfig:37:error: recursive dependency detected!
Kconfig:37: symbol E1 depends on E2 Kconfig:37: symbol E1 depends on E2
Kconfig:42: symbol E2 is implied by E1 Kconfig:42: symbol E2 is implied by E1
For a resolution refer to Documentation/kbuild/kconfig-language.txt For a resolution refer to Documentation/kbuild/kconfig-language.rst
subsection "Kconfig recursive dependency limitations" subsection "Kconfig recursive dependency limitations"
Kconfig:60:error: recursive dependency detected! Kconfig:60:error: recursive dependency detected!
Kconfig:60: symbol G depends on G Kconfig:60: symbol G depends on G
For a resolution refer to Documentation/kbuild/kconfig-language.txt For a resolution refer to Documentation/kbuild/kconfig-language.rst
subsection "Kconfig recursive dependency limitations" subsection "Kconfig recursive dependency limitations"
Kconfig:51:error: recursive dependency detected! Kconfig:51:error: recursive dependency detected!
Kconfig:51: symbol F2 depends on F1 Kconfig:51: symbol F2 depends on F1
Kconfig:49: symbol F1 default value contains F2 Kconfig:49: symbol F1 default value contains F2
For a resolution refer to Documentation/kbuild/kconfig-language.txt For a resolution refer to Documentation/kbuild/kconfig-language.rst
subsection "Kconfig recursive dependency limitations" subsection "Kconfig recursive dependency limitations"
sound/oss/dmasound/Kconfig
View file @ cd238eff
...@@ -11,7 +11,7 @@ config DMASOUND_ATARI ...@@ -11,7 +11,7 @@ config DMASOUND_ATARI
This driver is also available as a module ( = code which can be This driver is also available as a module ( = code which can be
inserted in and removed from the running kernel whenever you inserted in and removed from the running kernel whenever you
want). If you want to compile it as a module, say M here and read want). If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. <file:Documentation/kbuild/modules.rst>.
config DMASOUND_PAULA config DMASOUND_PAULA
tristate "Amiga DMA sound support" tristate "Amiga DMA sound support"
...@@ -25,7 +25,7 @@ config DMASOUND_PAULA ...@@ -25,7 +25,7 @@ config DMASOUND_PAULA
This driver is also available as a module ( = code which can be This driver is also available as a module ( = code which can be
inserted in and removed from the running kernel whenever you inserted in and removed from the running kernel whenever you
want). If you want to compile it as a module, say M here and read want). If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. <file:Documentation/kbuild/modules.rst>.
config DMASOUND_Q40 config DMASOUND_Q40
tristate "Q40 sound support" tristate "Q40 sound support"
...@@ -39,7 +39,7 @@ config DMASOUND_Q40 ...@@ -39,7 +39,7 @@ config DMASOUND_Q40
This driver is also available as a module ( = code which can be This driver is also available as a module ( = code which can be
inserted in and removed from the running kernel whenever you inserted in and removed from the running kernel whenever you
want). If you want to compile it as a module, say M here and read want). If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. <file:Documentation/kbuild/modules.rst>.
config DMASOUND config DMASOUND
tristate tristate
......
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