gen_init_cpio gets the current time and uses it for each symlink,
special file, and directory.  Grab the current time once and make it
possible to override it with the KBUILD_BUILD_TIMESTAMP variable for
reproducible builds.
Signed-off-by: NMichal Marek <mmarek@suse.cz>

Make it possible to override the user@host string displayed during boot
and in /proc/version by the environment variables KBUILD_BUILD_USER and
KBUILD_BUILD_HOST. Several distributions patch scripts/mkcompile_h to
achieve this, so let's provide an official way. Also, document the
KBUILD_BUILD_TIMESTAMP variable while at it.
Signed-off-by: NMichal Marek <mmarek@suse.cz>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

Add a 'W=1' Makefile switch which adds additional checking per build
object.

The idea behind this option is targeted at developers who, in the
process of writing their code, want to do the occasional

make W=1 [target.o]

and let gcc do more extensive code checking for them. Then, they
could eyeball the output for valid gcc warnings about various
bugs/discrepancies which are not reported during the normal build
process.

For more background information and a use case, read through this
thread: http://marc.info/?l=kernel-janitors&m=129802065918147&w=2

Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kbuild@vger.kernel.org
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Acked-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NBorislav Petkov <bp@alien8.de>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

Signed-off-by: NGilles Espinasse <g.esp@free.fr>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Usefull if building for sparc64 userland, because the
sparc and sparc64 userlands use the same 64-bit kernel,
making it impossible to always select the correct userland
architecture for the resulting debian package.

Might also be usefull, if you want a i386 userland with a amd64 kernel.

Example usage:
	make KBUILD_DEBARCH=i386 deb-pkg

LKML-reference: <alpine.DEB.2.02.1011051437500.13287@aurora.sdinet.de>
Signed-off-by: NAsbjoern Sloth Toennesen <asbjorn@asbjorn.biz>
Reviewed-by: NWANG Cong <xiyou.wangcong@gmail.com>
Acked-by: Nmaximilian attems <max@stro.at>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

Fixed some typos and wording.
Signed-off-by: NNicolas Kaiser <nikai@nikai.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It is now possible to assign options to AS and CC
on the command line - which is only used for built-in code.

{A,C}FLAGS_KERNEL was used both in the top-level Makefile
in the arch makefiles, thus users had no way to specify
additional options to AS, CC without overriding
the original value.

Introduce a new set of variables KBUILD_{A,C}FLAGS_KERNEL
that is used by arch specific files and free up
{A,C}FLAGS_KERNEL so they can be assigned on
the command line.

All arch Makefiles that used the old variables has been updated.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

It is now possible to assign options to AS, CC and LD
on the command line - which is only used when building modules.

{A,C,LD}FLAGS_MODULE was all used both in the top-level Makefile
in the arch makefiles, thus users had no way to specify
additional options to AS, CC, LD when building modules
without overriding the original value.

Introduce a new set of variables KBUILD_{A,C,LD}FLAGS_MODULE
that is used by arch specific files and free up
{A,C,LD}FLAGS_MODULE so they can be assigned on
the command line.

All arch Makefiles that used the old variables has been updated.

Note: Previously we had a MODFLAGS variable for both
AS and CC. But in favour of consistency this was dropped.
So in some cases arch Makefile has one assignmnet replaced by
two assignmnets.

Note2: MODFLAGS was not documented and is dropped
without any notice. I do not expect much/any breakage
from this.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Acked-by: Mike Frysinger <vapier@gentoo.org> [blackfin]
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> [avr32]
Signed-off-by: NMichal Marek <mmarek@suse.cz>

make ALLSOURCE_ARCHS=all tags
- Document this in kbuild.txt
Without this change you have to type each arch separately.
Signed-off-by: NJohn Kacur <jkacur@redhat.com>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

Signed-off-by: NKirill Smelkov <kirr@mns.spb.ru>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

To make it easier for module-init-tools and scripts like mkinitrd to
distinguish builtin and missing modules, install a modules.builtin file
listing all builtin modules. This is done by generating an additional
config file (tristate.conf) with tristate options set to uppercase 'Y'
or 'M'. If we source that config file, the builtin modules appear in
obj-Y.
Signed-off-by: NMichal Marek <mmarek@suse.cz>

Replace the use of CROSS_COMPILE to select a customized
installkernel script with the possibility to set INSTALLKERNEL
to select a custom installkernel script when running make:

    make INSTALLKERNEL=arm-installkernel install

With this patch we are now more consistent across
different architectures - they did not all support use
of CROSS_COMPILE.

The use of CROSS_COMPILE was a hack as this really belongs
to gcc/binutils and the installkernel script does not change
just because we change toolchain.

The use of CROSS_COMPILE caused troubles with an upcoming patch
that saves CROSS_COMPILE when a kernel is built - it would no
longer be installable.
[Thanks to Peter Z. for this hint]

This patch undos what Ian did in commit:

  0f8e2d62
  ("use ${CROSS_COMPILE}installkernel in arch/*/boot/install.sh")

The patch has been lightly tested on x86 only - but all changes
looks obvious.
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Acked-by: Mike Frysinger <vapier@gentoo.org> [blackfin]
Acked-by: Russell King <linux@arm.linux.org.uk> [arm]
Acked-by: Paul Mundt <lethal@linux-sh.org> [sh]
Acked-by: "H. Peter Anvin" <hpa@zytor.com> [x86]
Cc: Ian Campbell <icampbell@arcom.com>
Cc: Tony Luck <tony.luck@intel.com> [ia64]
Cc: Fenghua Yu <fenghua.yu@intel.com> [ia64]
Cc: Hirokazu Takata <takata@linux-m32r.org> [m32r]
Cc: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
Cc: Kyle McMartin <kyle@mcmartin.ca> [parisc]
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> [powerpc]
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> [s390]
Cc: Thomas Gleixner <tglx@linutronix.de> [x86]
Cc: Ingo Molnar <mingo@redhat.com> [x86]
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

Fix typos in the new kbuild.txt file.
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

This patch reintroduce the ALLSOURCE_ARCHS support for tags/TAGS/
cscope targets. The Kbuild previously has this feature, but after
moving the targets into scripts/tags.sh, ALLSOURCE_ARCHS disappears.

It's something like this:

	$ make ALLSOURCE_ARCHS="x86 mips arm" tags cscope
Signed-off-by: NJike Song <albcamus@gmail.com>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

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: NSam Ravnborg <sam@ravnborg.org>