Add kbuild.txt to Documentation/kbuild
More stuff can be added later - at least we have
som of the varous environment variables documented now.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Create a kconfig user assistance guide, with a few tips and hints
about using menuconfig, xconfig, and gconfig.
Mostly contains user interface, environment variables, and search topics,
along with mini.config/custom.config usage.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
There is a bunch of places in the build system where we do 'echo' to show
some nice status lines. This means we still get output when running in
silent mode. So declare a new KECHO variable that only does 'echo' when we
are in a suitable verbose build mode.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
[sam: added Documentation]
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
For the use case the hint describe a simple dependency is
enough.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
While select should be used with care, it is not actually evil.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
This patch adds a new (Kbuild) Makefile variable KBUILD_EXTRA_SYMBOLS.
The space separated list of file names assigned to KBUILD_EXTRA_SYMBOLS
is used when calling scripts/mod/modpost during stage 2 of the Kbuild
process for non-kernel-tree modules.
Signed-off-by: Richard Hacker <lerichi@gmx.net>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Add the possibility to import a value from the environment into kconfig
via the option syntax. Beside flexibility this has the advantage
providing proper dependencies.
Documented the options syntax.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Add a section on kconfig hints: how to do <something> in Kconfig files.
Fix a few typos/spellos.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Add kconfig-language docs for mainmenu, def_bool, and def_tristate.
Remove "requires" as a synonym of "depends on" since it was removed
from the parser in commit 247537b9a2.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
cc-cross-prefix is useful for the architecture that like
to provide a default CROSS_COMPILE value,
but may have several to select between.
Sample usage:
ifneq ($(SUBARCH),$(ARCH))
ifeq ($(CROSS_COMPILE),)
CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
endif
endif
Actual usage by the different archs will taken care of later.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Introduce ccflags-y, asflags-y and ldflags-y so we soon can
deprecate use of EXTRA_CFLAGS, EXTRA_AFLAGS and EXTRA_LDFLAGS.
This patch does not touch any in-tree users - thats next round.
Lets get this committed first and then fix the users of the
soon to be deprecated variants next.
The rationale behind this change is to introduce support for
makefile fragments like:
ccflags-$(CONFIG_WHATEVER_DEBUG) := -DDEBUG
As a replacement for the uglier:
ifeq ($(CONFIG_WHATEVER_DEBUG),y)
EXTRA_CFLAGS := -DDEBUG
endif
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
The variable CPPFLAGS is a wellknown variable and the usage by
kbuild may result in unexpected behaviour.
This patch replace use of CPPFLAGS with KBUILD_CPPFLAGS all over the
tree and enabling one to use:
make CPPFLAGS=...
to specify additional CPP commandline options.
Patch was tested on following architectures:
alpha, arm, i386, x86_64, mips, sparc, sparc64, ia64, m68k, s390
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
The variable AFLAGS is a wellknown variable and the usage by
kbuild may result in unexpected behaviour.
On top of that several people over time has asked for a way to
pass in additional flags to gcc.
This patch replace use of AFLAGS with KBUILD_AFLAGS all over
the tree.
Patch was tested on following architectures:
alpha, arm, i386, x86_64, mips, sparc, sparc64, ia64, m68k, s390
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
The variable CFLAGS is a wellknown variable and the usage by
kbuild may result in unexpected behaviour.
On top of that several people over time has asked for a way to
pass in additional flags to gcc.
This patch replace use of CFLAGS with KBUILD_CFLAGS all over the
tree and enabling one to use:
make CFLAGS=...
to specify additional gcc commandline options.
One usecase is when trying to find gcc bugs but other
use cases has been requested too.
Patch was tested on following architectures:
alpha, arm, i386, x86_64, mips, sparc, sparc64, ia64, m68k
Test was simple to do a defconfig build, apply the patch and check
that nothing got rebuild.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
EXTRA_ARFLAGS have never been used so no need to carry
around on this.
A google search did not reveal any external module
using this either.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Small error had sneaked in with respect to use
of LDFLAGS_$@. LDFLAGS_$@ is not valid in normal
kbuild files so do not say so.
Fix a reference bug too.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
A warning note from Sam Ravnborg about kconfig's select evilness,
dependencies and the future (slightly corrected).
Signed-off-by: Jarek Poplawski <jarkao2@o2.pl>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The Makefile fragment in Documentation/kbuild/modules.txt looks to be
missing some braces.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Standardize the miniscule percentage of occurrences of "depends" in
Kconfig files to "depends on", and update kconfig-language.txt to
reflect that.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
This patch fixes typos in various Documentation txts. The patch addresses some
misc words.
Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
While reading this I noticed that the contents of this document list
section "3.8 Command line dependency" but it doesn't exist in the document.
Signed-off-by: Daniel Walker <dwalker@mvista.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch fixes typos in various Documentation txts. The patch addresses
some words starting with the letter 'S'.
Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Alan Cox <alan@redhat.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
... instead of using a CONFIG option. The config option still controls
if the resulting executable actually has unwind information.
This is useful to prevent compilation errors when users select
CONFIG_STACK_UNWIND on old binutils and also allows to use
CFI in the future for non kernel debugging applications.
Cc: jbeulich@novell.com
Cc: sam@ravnborg.org
Signed-off-by: Andi Kleen <ak@suse.de>
I noticed a few typos while reading makefiles.txt to learn about the
kbuild system. Attached is a patch against 2.6.18 to fix them.
Remove trailing whitespace while we are there..
Signed-off-by: Bryce Harrington <bryce@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
I have done a look-through through Documentation/kbuild/ and my corrections
(proposed) are attached.
Cc'ed are original author Michael (responsible for comitting changes to
these files?), Sam (kbuild maintainer), Adrian (-trivial maintainer).
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
I have done a look-through through Documentation/kbuild/ and my corrections
(proposed) are attached.
Cc'ed are original author Michael (responsible for comitting changes to
these files?), Sam (kbuild maintainer), Adrian (-trivial maintainer).
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
I have done a look-through through Documentation/kbuild/ and my corrections
(proposed) are attached.
Cc'ed are original author Michael (responsible for comitting changes to
these files?), Sam (kbuild maintainer), Adrian (-trivial maintainer).
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
The latest toolchains can produce a new ELF section in DSOs and
dynamically-linked executables. The new section ".gnu.hash" replaces
".hash", and allows for more efficient runtime symbol lookups by the
dynamic linker. The new ld option --hash-style={sysv|gnu|both} controls
whether to produce the old ".hash", the new ".gnu.hash", or both. In some
new systems such as Fedora Core 6, gcc by default passes --hash-style=gnu
to the linker, so that a standard invocation of "gcc -shared" results in
producing a DSO with only ".gnu.hash". The new ".gnu.hash" sections need
to be dealt with the same way as ".hash" sections in all respects; only the
dynamic linker cares about their contents. To work with older dynamic
linkers (i.e. preexisting releases of glibc), a binary must have the old
".hash" section. The --hash-style=both option produces binaries that a new
dynamic linker can use more efficiently, but an old dynamic linker can
still handle.
The new section runs afoul of the custom linker scripts used to build vDSO
images for the kernel. On ia64, the failure mode for this is a boot-time
panic because the vDSO's PT_IA_64_UNWIND segment winds up ill-formed.
This patch addresses the problem in two ways.
First, it mentions ".gnu.hash" in all the linker scripts alongside ".hash".
This produces correct vDSO images with --hash-style=sysv (or old tools),
with --hash-style=gnu, or with --hash-style=both.
Second, it passes the --hash-style=sysv option when building the vDSO
images, so that ".gnu.hash" is not actually produced. This is the most
conservative choice for compatibility with any old userland. There is some
concern that some ancient glibc builds (though not any known old production
system) might choke on --hash-style=both binaries. The optimizations
provided by the new style of hash section do not really matter for a DSO
with a tiny number of symbols, as the vDSO has. If someone wants to use
=gnu or =both for their vDSO builds and worry less about that
compatibility, just change the option and the linker script changes will
make any choice work fine.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add option for stripping modules while installing them.
This function adds support for stripping modules while they are being
installed. CONFIG_DEBUG_KERNEL (which will probably become more
popular as developers use kdump) causes the size of the installed
modules to grow by a factor of 9 or so.
Some kernel package systems solve this problem by stripping the debug
information from /lib/modules after running "make modules_install",
but that may not work for people who are installing directly into
/lib/modules --- root partitions that were sized to handle 16 megs
worth of modules may not be quite so happy with 145 megs of modules,
so the "make modules_install" never succeeds.
This patch allows such users to request modules_install to strip the
modules as they are installed.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
As noted by Roland Dreier <rdreier@cisco.com> makefiles.txt told
one to use the name 'Kbuild' as preferred name for kbuild files.
This is not yet true so let makefiles.txt reflect reality.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Move $(CC) support functions to Kbuild.include so they are available
in the kbuild files.
In addition the following was done:
o as-option documented in Documentation/kbuild/makefiles.txt
o Moved documentation to new section to match
new scope of functions
o added cc-ifversion used to conditionally select a text string
dependent on actual $(CC) version
o documented cc-ifversion
o change so Kbuild.include is read before the kbuild file
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
With following patch a second option is enabled to obtain
symbol information from a second external module when a
external module is build.
The recommended approach is to use a common kbuild file but
that may be impractical in certain cases.
With this patch one can copy over a Module.symvers from one
external module to make symbols (and symbol versions) available
for another external module.
Updated documentation in Documentation/kbuild/modules.txt
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Support building individual files when dealing with separate modules.
So say you have a module named "foo" which consist of two .o files bar.o
and fun.o.
You can then do:
make -C $KERNELSRC M=`pwd` bar.o
make -C $KERNELSRC M=`pwd` bar.lst
make -C $KERNELSRC M=`pwd` bar.i
make -C $KERNELSRC M=`pwd` / <= will build all .o files
and link foo.o
make -C $KERNELSRC M=`pwd` foo.ko <= will build the module
and do the modpost step
to create foo.ko
The above will also work if the external module is placed in a
subdirectory using a hirachy of kbuild files.
Thanks to Andreas Gruenbacher <agruen@suse.de> for initial feature
request / bug report.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
This was causing some ordering problems. Remove the up-front evaluation
and just revaluate the compiler version each time we need it.
(The up-front evaluation was problematic because some architectures modify
the value of $(CC)).
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Update modules.txt with info how to build external modules
with files in several directories.
The question popped up on lkml often enough to warrant this,
let's see if people read this stuff - or google hits it.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
First off, thanks for the kbuild docs, they are very useful! Second,
I've attached a patch to modules.txt (from 2.6.14.2) with a "compile"
fix to a Makefile example, and some trivial spelling/grammar nits.
Please let me know if you want the patch in some other format (eg not
MIME), or if I should go bother someone else about it.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
When introducing the generic asm-offsets.h support the dependency
chain for the prepare targets was changed. All build scripts expecting
include/asm/asm-offsets.h to be made when using the prepare target would broke.
With the limited number of prepare targets left in arch Makefiles
the trivial solution was to introduce a new arch specific target: archprepare
The dependency chain looks like this now:
prepare
|
+--> prepare0
|
+--> archprepare
|
+--> scripts_basic
+--> prepare1
|
+---> prepare2
|
+--> prepare3
So prepare 3 is processed before prepare2 etc.
This guaantees that the asm symlink, version.h, scripts_basic
are all updated before archprepare is processed.
prepare0 which build the asm-offsets.h file will need the
actions performed by archprepare.
The head target is now named prepare, because users scripts will most
likely use that target, but prepare-all has been kept for compatibility.
Updated Documentation/kbuild/makefiles.txt.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Whitespace is significant for make, and I just fought against this... so
please apply this patch.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
