kbuild: Use CRC32 and a 1MiB dictionary for XZ compressed modules

Kmod is now (since kmod commit 09c9f8c5df04 ("libkmod: Use kernel
decompression when available")) using the kernel decompressor, when
loading compressed modules.

However, the kernel XZ decompressor is XZ Embedded, which doesn't
handle CRC64 and dictionaries larger than 1MiB.

Use CRC32 and 1MiB dictionary when XZ compressing and installing
kernel modules.

Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1050582
Signed-off-by: Martin Nybo Andersen <tweek@tweek.dk>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

kbuild: avoid long argument lists in make modules_install

Running "make modules_install" may fail with

make[2]: execvp: /bin/sh: Argument list too long

if many modules are built and INSTALL_MOD_PATH is long. This is because
scripts/Makefile.modinst creates all directories with one mkdir command.
Use $(foreach ...) instead to prevent an excessive argument list.

Fixes: 2dfec887c0fd ("kbuild: reduce the number of mkdir calls during modules_install")
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

kbuild: support modules_sign for external modules as well

The modules_sign target is currently only available for in-tree modules,
but it actually works for external modules as well.

Move the modules_sign rule to the common part.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

kbuild: support 'make modules_sign' with CONFIG_MODULE_SIG_ALL=n

Commit d890f510c8e4 ("MODSIGN: Add modules_sign make target") introduced
'make modules_sign' to manually sign modules.

Some time later, commit d9d8d7ed498e ("MODSIGN: Add option to not sign
modules during modules_install") introduced CONFIG_MODULE_SIG_ALL.
If it was disabled, mod_sign_cmd was set to no-op ('true' command).
It affected not only 'make modules_install' but also 'make modules_sign'.
With CONFIG_MODULE_SIG_ALL=n, neither modules_install nor modules_sign
is able to sign modules.

Kbuild has kept that behavior, and nobody has complained about it, but
I think it is weird.

CONFIG_MODULE_SIG_ALL=n should turn off signing only for modules_install.
If users want to sign modules manually, modules_sign should be offered.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

kbuild: move more module installation code to scripts/Makefile.modinst

Move more relevant code to scripts/Makefile.modinst.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

kbuild: reduce the number of mkdir calls during modules_install

Calling 'mkdir' for every module results in redundant syscalls.

Use $(sort ...) to drop the duplicated directories.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

kbuild: move depmod rule to scripts/Makefile.modinst

depmod is a part of the module installation.

scripts/Makefile.modinst is a better place to run it.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

kbuild: Modify default INSTALL_MOD_DIR from extra to updates

The default INSTALL_MOD_DIR of using the /lib/modules/$(uname -r)/extra
directory for external modules assumes distributions will have something
like /etc/depmod.d/dist.conf with:

search updates extra built-in

However, only some Red Hat releases have and use the "extra" stuff for
years now. Meanwhile, the depmod.c tool in kmod has *forever* used
the "updates" directory as part of the search path by default *if*
your distribution does not have any depmod.d configuration.

If you compile and install an external module today, even upstream
kernel mock drivers (tools/testing/cxl) the modules_install target
will pick up the new drivers but will not allow override of drivers
from updates to override built-in ones.

Since module-init-tools was deprecated over 11 years ago and now kmod
has since its inception used the "updates" directory as part of its
default search path to allow overrides, and since the "extra" stuff
was in practice only used by Red Hat stuff, use the more distro
agnostic override path "updates" to allow external modules to
also override proper production kernel modules.

This would allow mocking drivers tools to not have to muck with
depmod.d config files or assume that your distro will have extra
on a configuration file over built-in.

With today's default you end up actually *crashing* Linux when
trying to load cxl_test with the default "extra" [0] directory being
used. This fixes that and allows other mocking drivers to do
less work.

[0] https://lkml.kernel.org/r/20221209062919.1096779-1-mcgrof@kernel.org

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

kbuild: modinst: Fix build error when CONFIG_MODULE_SIG_KEY is a PKCS#11 URI

When CONFIG_MODULE_SIG_KEY is PKCS#11 URI (pkcs11:*), signing of modules
fails:

scripts/sign-file sha256 /.../linux/pkcs11:token=foo;object=bar;pin-value=1111 certs/signing_key.x509 /.../kernel/crypto/tcrypt.ko
Usage: scripts/sign-file [-dp] <hash algo> <key> <x509> <module> [<dest>]
scripts/sign-file -s <raw sig> <hash algo> <x509> <module> [<dest>]

First, we need to avoid adding the $(srctree)/ prefix to the URL.

Second, since the kconfig string values no longer include quotes, we need to add
them again when passing a PKCS#11 URI to sign-file. This avoids
splitting by the shell if the URI contains semicolons.

Fixes: 4db9c2e3d055 ("kbuild: stop using config_filename in scripts/Makefile.modsign")
Fixes: 129ab0d2d9f3 ("kbuild: do not quote string values in include/config/auto.conf")
Signed-off-by: Jan Luebbe <jlu@pengutronix.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

kbuild: change module.order to list *.o instead of *.ko

scripts/Makefile.build replaces the suffix .o with .ko, then
scripts/Makefile.modpost calls the sed command to change .ko back
to the original .o suffix.

Instead of converting the suffixes back-and-forth, store the .o paths
in modules.order, and replace it with .ko in 'make modules_install'.

This avoids the unneeded sed command.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>

kbuild: add read-file macro

Since GNU Make 4.2, $(file ...) supports the read operater '<', which
is useful to read a file without forking a new process. No warning is
shown even if the input file is missing.

For older Make versions, it falls back to the cat command.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Reviewed-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Tested-by: Alexander Lobakin <alexandr.lobakin@intel.com>

kbuild: do not sort after reading modules.order

modules.order lists modules in the deterministic order (that is why
"modules order"), and there is no duplication in the list.

$(sort ) is pointless.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

kbuild: error out if $(INSTALL_MOD_PATH) contains % or :

If the directory path given to INSTALL_MOD_PATH contains % or :,
the module_install fails.

% is used in pattern rules, and : as the separator of dependencies.

Bail out with a clearer error message.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@avm.de>

kbuild: remove unused cmd_none in scripts/Makefile.modinst

Commit 65ce9c38326e ("kbuild: move module strip/compression code into
scripts/Makefile.modinst") added this unused code.

Perhaps, I thought cmd_none was useful for CONFIG_MODULE_COMPRESS_NONE,
but I did not use it after all.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>

kbuild: do not quote string values in include/config/auto.conf

The previous commit fixed up all shell scripts to not include
include/config/auto.conf.

Now that include/config/auto.conf is only included by Makefiles,
we can change it into a more Make-friendly form.

Previously, Kconfig output string values enclosed with double-quotes
(both in the .config and include/config/auto.conf):

CONFIG_X="foo bar"

Unlike shell, Make handles double-quotes (and single-quotes as well)
verbatim. We must rip them off when used.

There are some patterns:

[1] $(patsubst "%",%,$(CONFIG_X))
[2] $(CONFIG_X:"%"=%)
[3] $(subst ",,$(CONFIG_X))
[4] $(shell echo $(CONFIG_X))

These are not only ugly, but also fragile.

[1] and [2] do not work if the value contains spaces, like
CONFIG_X=" foo bar "

[3] does not work correctly if the value contains double-quotes like
CONFIG_X="foo\"bar"

[4] seems to work better, but has a cost of forking a process.

Anyway, quoted strings were always PITA for our Makefiles.

This commit changes Kconfig to stop quoting in include/config/auto.conf.

These are the string type symbols referenced in Makefiles or scripts:

ACPI_CUSTOM_DSDT_FILE
ARC_BUILTIN_DTB_NAME
ARC_TUNE_MCPU
BUILTIN_DTB_SOURCE
CC_IMPLICIT_FALLTHROUGH
CC_VERSION_TEXT
CFG80211_EXTRA_REGDB_KEYDIR
EXTRA_FIRMWARE
EXTRA_FIRMWARE_DIR
EXTRA_TARGETS
H8300_BUILTIN_DTB
INITRAMFS_SOURCE
LOCALVERSION
MODULE_SIG_HASH
MODULE_SIG_KEY
NDS32_BUILTIN_DTB
NIOS2_DTB_SOURCE
OPENRISC_BUILTIN_DTB
SOC_CANAAN_K210_DTB_SOURCE
SYSTEM_BLACKLIST_HASH_LIST
SYSTEM_REVOCATION_KEYS
SYSTEM_TRUSTED_KEYS
TARGET_CPU
UNUSED_KSYMS_WHITELIST
XILINX_MICROBLAZE0_FAMILY
XILINX_MICROBLAZE0_HW_VER
XTENSA_VARIANT_NAME

I checked them one by one, and fixed up the code where necessary.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

kbuild: stop using config_filename in scripts/Makefile.modsign

Toward the goal of removing the config_filename macro, drop
the double-quotes and add $(srctree)/ prefix in an ad hoc way.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@avm.de>

kbuild: add support for zstd compressed modules

kmod 28 supports modules compressed in zstd format so let's add this
possibility to kernel.

Signed-off-by: Piotr Gorski <lucjan.lucjanov@gmail.com>
Reviewed-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

kbuild: merge scripts/Makefile.modsign to scripts/Makefile.modinst

scripts/Makefile.modsign is a subset of scripts/Makefile.modinst,
and duplicates the code. Let's merge them.

By the way, you do not need to run 'make modules_sign' explicitly
because modules are signed as a part of 'make modules_install' when
CONFIG_MODULE_SIG_ALL=y. If CONFIG_MODULE_SIG_ALL=n, mod_sign_cmd is
set to 'true', so 'make modules_sign' is not functional.

In my understanding, the reason of still keeping this is to handle
corner cases like commit 64178cb62c32 ("builddeb: fix stripped module
signatures if CONFIG_DEBUG_INFO and CONFIG_MODULE_SIG_ALL are set").

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

kbuild: move module strip/compression code into scripts/Makefile.modinst

Both mod_strip_cmd and mod_compress_cmd are only used in
scripts/Makefile.modinst, hence there is no good reason to define them
in the top Makefile. Move the relevant code to scripts/Makefile.modinst.

Also, show separate log messages for each of install, strip, sign, and
compress.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

kbuild: refactor scripts/Makefile.modinst

scripts/Makefile.modinst is ugly and weird in multiple ways; it
specifies real files $(modules) as phony, makes directory manipulation
needlessly too complicated.

Clean up the Makefile code, and show the full path of installed modules
in the log.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

kbuild: prefix $(srctree)/ to some included Makefiles

VPATH is used in Kbuild to make pattern rules search for prerequisites
in both $(objtree) and $(srctree). Some of *.c, *.S files are not real
sources, but generated by tools such as flex, bison, perl.

In contrast, I doubt the benefit of --include-dir=$(abs_srctree) because
it is always clear which Makefiles are real sources, and which are not.

So, my hope is to add $(srctree)/ prefix to all check-in Makefiles,
then remove --include-dir=$(abs_srctree) flag in the future.

I am touching only some Kbuild core parts for now. Treewide fixes will
be needed to achieve this goal.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

kbuild: modinst: read modules.order instead of $(MODVERDIR)/*.mod

Towards the goal of removing MODVERDIR, read out modules.order to get
the list of modules to be installed. This is simpler than parsing *.mod
files in $(MODVERDIR).

For external modules, $(KBUILD_EXTMOD)/modules.order should be read.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Revert "modsign: Abort modules_install when signing fails"

This reverts commit caf6fe91ddf62a96401e21e9b7a07227440f4185.

The commit was fine but is no longer needed as of commit 3a2429e1faf4
("kbuild: change if_changed_rule for multi-line recipe"). Let's go
back to using ";" to be consistent.

For some discussion, see:

https://lkml.kernel.org/r/CAK7LNASde0Q9S5GKeQiWhArfER4S4wL1=R_FW8q0++_X3T5=hQ@mail.gmail.com

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

kbuild: remove duplicated comments about PHONY

The comment is the same as in the top-level Makefile.

Also, the comments contain typos:
- the .PHONY variable -> the PHONY variable
- se we can ... -> so we can ...

Instead of fixing the typos, just remove the duplicated comments.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

modsign: Abort modules_install when signing fails

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: David Howells <dhowells@redhat.com>

kbuild: handle module compression while running 'make modules_install'.

Since module-init-tools (gzip) and kmod (gzip and xz) support compressed
modules, it could be useful to include a support for compressing modules
right after having them installed. Doing this in kbuild instead of per
distro can permit to make this kind of usage more generic.

This patch add a Kconfig entry to "Enable loadable module support" menu
and let you choose to compress using gzip (default) or xz.

Both gzip and xz does not used any extra -[1-9] option since Andi Kleen
and Rusty Russell prove no gain is made using them. gzip is called with -n
argument to avoid storing original filename inside compressed file, that
way we can save some more bytes.

On a v3.16 kernel, 'make allmodconfig' generated 4680 modules for a
total of 378MB (no strip, no sign, no compress), the following table
shows observed disk space gain based on the allmodconfig .config :

| time |
+-------------+-----------------+
| manual .ko | make | size | percent
| compression | modules_install | | gain
+-------------+-----------------+------+--------
- | | 18.61s | 378M |
GZIP | 3m16s | 3m37s | 102M | 73.41%
XZ | 5m22s | 5m39s | 77M | 79.83%

The gain for restricted environnement seems to be interesting while
uncompress can be time consuming but happens only while loading a module,
that is generally done only once.

This is fully compatible with signed modules while the signed module is
compressed. module-init-tools or kmod handles decompression
and provide to other layer the uncompressed but signed payload.

Reviewed-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Bertrand Jacquin <beber@meleeweb.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

modinst: wrap long lines in order to enhance cmd_modules_install

Note: shouldn't we use 'install -D $(2)/$@ $@' instead of mkdir
and cp ?

Reviewed-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Bertrand Jacquin <beber@meleeweb.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

kbuild: fix comment in Makefile.modinst

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

modules: don't break modules_install on external modules with no key.

The script still spits out an error ("Can't read private key") but we
don't break modules_install.

Reported-by: Bruno Wolff III <bruno@wolff.to>
Original-patch-by: Josh Boyer <jwboyer@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

kbuild: sign the modules at install time

Linus deleted the old code and put signing on the install command,
I fixed it to extract the keyid and signer-name within sign-file
and cleaned up that script now it always signs in-place.

Some enthusiast should convert sign-key to perl and pull
x509keyid into it.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/Makefile.modpost: error in finding modules from .mod files.

This error may happen when the user's id or path includes .ko string.
For example, user's id is xxx.ko and building test.ko module,
the test.mod file lists ko name and all object files.
/home/xxx.ko/kernel_dev/device/drivers/test.ko
/home/xxx.ko/kernel_dev/device/drivers/test_main.o
/home/xxx.ko/kernel_dev/device/drivers/test_io.o ...
Current Makefile.modpost and Makefile.modinst find and list up not
only test.ko but also other object files.
because all of object file's path includes .ko string.
This is a patch to fix it.

Signed-off-by: Gunho Lee <gunho.lee@lge.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>

Revert "kbuild: strip generated symbols from *.ko"

This reverts commit ad7a953c522ceb496611d127e51e278bfe0ff483.

And commit: ("allow stripping of generated symbols under CONFIG_KALLSYMS_ALL")
9bb482476c6c9d1ae033306440c51ceac93ea80c

These stripping patches has caused a set of issues:

1) People have reported compatibility issues with binutils due to
lack of support for `--strip-unneeded-symbols' with objcopy 2.15.92.0.2
Reported by: Wenji
2) ccache and distcc no longer works as expeced
Reported by: Ted, Roland, + others
3) The installed modules increased a lot in size
Reported by: Ted, Davej + others

Reported-by: Wenji Huang <wenji.huang@oracle.com>
Reported-by: "Theodore Ts'o" <tytso@mit.edu>
Reported-by: Dave Jones <davej@redhat.com>
Reported-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

kbuild: strip generated symbols from *.ko

This patch changes the way __crc_ symbols are being resolved from
using ld to do so to using the assembler, thus allowing these symbols
to be marked local (the linker creates then as global ones) and hence
allow stripping (for modules) or ignoring (for vmlinux) them. While at
this, also strip other generated symbols during module installation.

One potentially debatable point is the handling of the flags passeed
to gcc when translating the intermediate assembly file into an object:
passing $(c_flags) unchanged doesn't work as gcc passes --gdwarf2 to
gas whenever is sees any -g* option, even for -g0, and despite the
fact that the compiler would have already produced all necessary debug
info in the C->assembly translation phase. I took the approach of just
filtering out all -g* options, but an alternative to such negative
filtering might be to have a positive filter which might, in the ideal
case allow just all the -Wa,* options to pass through.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

kbuild: fix installing external modules

Eric Sandeen <sandeen@redhat.com> reported:
Installing external modules is supposed to put them in some path
under /lib/modules/<version>/extra/subdir/, but this change:
http://linux.bkbits.net:8080/linux-2.6/?PAGE=cset&REV=1.1982.9.23
makes them go under /lib/modules/<version>/extrasubdir

(for example, make M=fs/ext3 modules_install puts ext3.ko in
/lib/modules/<version>/extrafs/ext3.ko)

This was the case only when specifying a trailing slash to M=..

Fixed by removing trailing slash if present so
we correctly match dir part of target.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Eric Sandeen <sandeen@redhat.com>

kbuild: add option for stripping modules while installing them

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>

kbuild: change kbuild to not rely on incorrect GNU make behavior

The kbuild system takes advantage of an incorrect behavior in GNU make.
Once this behavior is fixed, all files in the kernel rebuild every time,
even if nothing has changed. This patch ensures kbuild works with both
the incorrect and correct behaviors of GNU make.

For more details on the incorrect behavior, see:

http://lists.gnu.org/archive/html/bug-make/2006-03/msg00003.html

Changes in this patch:
- Keep all targets that are to be marked .PHONY in a variable, PHONY.
- Add .PHONY: $(PHONY) to mark them properly.
- Remove any $(PHONY) files from the $? list when determining whether
targets are up-to-date or not.

Signed-off-by: Paul Smith <psmith@gnu.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

kbuild: introduce Kbuild.include

Kbuild.include is a placeholder for definitions originally present in
both the top-level Makefile and scripts/Makefile.build.
There were a slight difference in the filechk definition, so the most videly
used version was kept and usr/Makefile was adopted for this syntax.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
---

Linux-2.6.12-rc2

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!