The 'define' ... 'endef' directive is useful to confine a series of
shell commands into a single macro:

  define foo
          [action1]
          [action2]
          [action3]
  endif

Each action is executed in a separate subshell.

However, rule_cc_o_c and rule_as_o_S in scripts/Makefile.build are
written as follows (with a trailing semicolon in each cmd_*):

  define rule_cc_o_c
          [action1] ; \
          [action2] ; \
          [action3] ;
  endef

All shell commands are concatenated with '; \' so that it looks like
a single command from the Makefile point of view. This does not
exploit the benefits of 'define' ... 'endef' form because a single
shell command can be more simply written, like this:

  rule_cc_o_c = \
          [action1] ; \
          [action2] ; \
          [action3] ;

I guess the intention for the command concatenation was to let the
'@set -e' in if_changed_rule cover all the commands.

We can improve the readability by moving '@set -e' to the 'cmd' macro.
The combo of $(call echo-cmd,*) $(cmd_*) in rule_cc_o_c and rule_as_o_S
have been replaced with $(call cmd,*). The trailing back-slashes have
been removed.

Here is a note about the performance: the commands in rule_cc_o_c and
rule_as_o_S were previously executed all together in a single subshell,
but now each line in a separate subshell. This means Make will spawn
extra subshells [1]. I measured the build performance for
  x86_64_defconfig + CONFIG_MODVERSIONS + CONFIG_TRIM_UNUSED_KSYMS
and I saw slight performance regression, but I believe code readability
and maintainability wins.

[1] Precisely, GNU Make may optimize this by executing the command
    directly instead of forking a subshell, if no shell special
    characters are found in the command line and omitting the subshell
    will not change the behavior.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

My main motivation of this commit is to clean up scripts/Kbuild.include
and scripts/Makefile.build.

Currently, CONFIG_TRIM_UNUSED_KSYMS works with a tricky gimmick;
possibly exported symbols are detected by letting $(CPP) replace
EXPORT_SYMBOL* with a special string '=== __KSYM_*===', which is
post-processed by sed, and passed to fixdep. The extra preprocessing
is costly, and hacking cmd_and_fixdep is ugly.

I came up with a new way to find exported symbols; insert a dummy
symbol __ksym_marker_* to each potentially exported symbol. Those
dummy symbols are picked up by $(NM), post-processed by sed, then
appended to .*.cmd files. I collected the post-process part to a
new shell script scripts/gen_ksymdeps.sh for readability. The dummy
symbols are put into the .discard.* section so that the linker
script rips them off the final vmlinux or modules.

A nice side-effect is building with CONFIG_TRIM_UNUSED_KSYMS will
be much faster.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NNicolas Pitre <nico@linaro.org>

Let $(CC) compile objects into normal files *.o instead of .tmp_*.o
whether CONFIG_MODVERSIONS is enabled or not. With this, the input
file for objtool is always *.o so objtool_o can go away.

I guess the reason of using .tmp_*.o for intermediate objects was
to avoid leaving incomplete *.o file (, whose timestamp says it is
up-to-date) when the genksyms tool failed for some reasons.

It no longer matters because any targets are deleted on errors since
commit 9c2af1c7 ("kbuild: add .DELETE_ON_ERROR special target").
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

This is executed inside the if_changed_rule, which already sets
'set -e'.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

The filechk macro in scripts/Kbuild.include already sets 'set -e'.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Currently, fixdep writes dependencies to .*.tmp, which is renamed to
.*.cmd after everything succeeds. This is a very safe way to avoid
corrupted .*.cmd files. The if_changed_dep has carried this safety
mechanism since it was added in 2002.

If fixdep fails for some reasons or a user terminates the build while
fixdep is running, the incomplete output from the fixdep could be
troublesome.

This is my insight about some bad scenarios:

[1] If the compiler succeeds to generate *.o file, but fixdep fails
    to write necessary dependencies to .*.cmd file, Make will miss
    to rebuild the object when headers or CONFIG options are changed.
    In this case, fixdep should not generate .*.cmd file at all so
    that 'arg-check' will surely trigger the rebuild of the object.

[2] A partially constructed .*.cmd file may not be a syntactically
    correct makefile. The next time Make runs, it would include it,
    then fail to parse it. Once this happens, 'make clean' is be the
    only way to fix it.

In fact, [1] is no longer a problem since commit 9c2af1c7 ("kbuild:
add .DELETE_ON_ERROR special target"). Make deletes a target file on
any failure in its recipe. Because fixdep is a part of the recipe of
*.o target, if it fails, the *.o is deleted anyway. However, I am a
bit worried about the slight possibility of [2].

So, here is a solution. Let fixdep directly write to a .*.cmd file,
but allow makefiles to include it only when its corresponding target
exists.

This effectively reverts commit 2982c953 ("kbuild: remove redundant
$(wildcard ...) for cmd_files calculation"), and commit 00d78ab2
("kbuild: remove dead code in cmd_files calculation in top Makefile")
because now we must check the presence of targets.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Now that 'archprepare' depends on 'scripts', Kbuild can descend into
scripts/gcc-plugins in a more standard way.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NKees Cook <keescook@chromium.org>

I am eagar to build under the scripts/ directory only with $(HOSTCC),
but scripts/mod/ highly depends on the $(CC) and target arch headers.
That it why the 'scripts' target must depend on 'asm-generic',
'gcc-plugins', and $(autoksyms_h).

Move it to the 'prepare0' stage. I know this is a cheesy workaround,
but better than the current situation.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

This will fit better in check_exports() than add_versions().
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Probably, this is just a matter of the order of error/warning
messages. Merge the two for-loops.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

You do not need to iterate over all modules for resetting ->seen flag
because add_depends() is only interested in modules that export symbols
referenced from the given 'mod'.

This also avoids shadowing the 'modules' parameter of add_depends().
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Use specific prototype instead of an opaque pointer so that the
compiler can catch function prototype mismatch.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NMathieu Malaterre <malat@debian.org>

Commit e49ce141 ("modpost: use linker section to generate table.")
was not so cool as we had expected first; it ended up with ugly section
hacks when commit dd2a3aca ("mod/file2alias: make modpost compile
on darwin again") came in.

Given a certain degree of unknowledge about the link stage of host
programs, I really want to see simple, stupid table lookup so that
this works in the same way regardless of the underlying executable
format.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NMathieu Malaterre <malat@debian.org>

During development of a serial console driver with a gcc 8.2.0
toolchain for RISC-V, the following modpost warning appeared:

----
WARNING: vmlinux.o(.data+0x19b10): Section mismatch in reference from the variable .LANCHOR1 to the function .init.text:sifive_serial_console_setup()
The variable .LANCHOR1 references
the function __init sifive_serial_console_setup()
If the reference is valid then annotate the
variable with __init* or __refdata (see linux/init.h) or name the variable:
*_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console
----

".LANCHOR1" is an ELF local symbol, automatically created by gcc's section
anchor generation code:

https://gcc.gnu.org/onlinedocs/gccint/Anchored-Addresses.html

https://gcc.gnu.org/git/?p=gcc.git;a=blob;f=gcc/varasm.c;h=cd9591a45617464946dcf9a126dde277d9de9804;hb=9fb89fa845c1b2e0a18d85ada0b077c84508ab78#l7473

This was verified by compiling the kernel with -fno-section-anchors
and observing that the ".LANCHOR1" ELF local symbol disappeared, and
modpost no longer warned about the section mismatch.  The serial
driver code idiom triggering the warning is standard Linux serial
driver practice that has a specific whitelist inclusion in modpost.c.

I'm neither a modpost nor an ELF expert, but naively, it doesn't seem
useful for modpost to report section mismatch warnings caused by ELF
local symbols by default.  Local symbols have compiler-generated
names, and thus bypass modpost's whitelisting algorithm, which relies
on the presence of a non-autogenerated symbol name.  This increases
the likelihood that false positive warnings will be generated (as in
the above case).

Thus, disable section mismatch reporting on ELF local symbols.  The
rationale here is similar to that of commit 2e3a10a1 ("ARM: avoid
ARM binutils leaking ELF local symbols") and of similar code already
present in modpost.c:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/scripts/mod/modpost.c?h=v4.19-rc4&id=7876320f88802b22d4e2daf7eb027dd14175a0f8#n1256

This third version of the patch implements a suggestion from Masahiro
Yamada <yamada.masahiro@socionext.com> to restructure the code as an
additional pattern matching step inside secref_whitelist(), and
further improves the patch description.
Signed-off-by: NPaul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Drop modpost command line switches that are no longer used by
makefile.modpost, upon request from Sam Ravnborg <sam@ravnborg.org>,
who wrote:

    modpost is not supposed to be used outside the kernel build. [...]
    I checked if there were any options supported by modpost that
    was not configurable in Makefile.modpost.
    And I could see that the -M and -K options in getopt() were leftovers.
    The code that used these option was dropped in:
    commit a8773769 ("Kbuild: clear marker out of modpost")

    Could you add a patch that delete these on top of what you already have.

https://lore.kernel.org/lkml/20181020140835.GA3351@ravnborg.org/Suggested-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NPaul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

git-diff-index does not refresh the index for you, so using it for a
"-dirty" check can give misleading results. Commit 6147b1cf
("scripts/setlocalversion: git: Make -dirty check more robust") tried to
fix this by switching to git-status, but it overlooked the fact that
git-status also writes to the .git directory of the source tree, which
is definitely not kosher for an out-of-tree (O=) build. That is getting
reverted.

Fortunately, git-status now supports avoiding writing to the index via
the --no-optional-locks flag, as of git 2.14. It still calculates an
up-to-date index, but it avoids writing it out to the .git directory.

So, let's retry the solution from commit 6147b1cf using this new
flag first, and if it fails, we assume this is an older version of git
and just use the old git-diff-index method.

It's hairy to get the 'grep -vq' (inverted matching) correct by stashing
the output of git-status (you have to be careful about the difference
betwen "empty stdin" and "blank line on stdin"), so just pipe the output
directly to grep and use a regex that's good enough for both the
git-status and git-diff-index version.

Cc: Christian Kujau <lists@nerdbynature.de>
Cc: Guenter Roeck <linux@roeck-us.net>
Suggested-by: NAlexander Kapshuk <alexander.kapshuk@gmail.com>
Signed-off-by: NBrian Norris <briannorris@chromium.org>
Tested-by: NGenki Sky <sky@genki.is>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

If an ARM mapping symbol shares an address with a valid symbol,
find_elf_symbol can currently return the mapping symbol instead, as the
symbol is not validated. This can result in confusing warnings:

  WARNING: vmlinux.o(.text+0x18f4028): Section mismatch in reference
  from the function set_reset_devices() to the variable .init.text:$x.0

This change adds a call to is_valid_name to find_elf_symbol, similarly
to how it's already used in find_elf_symbol2.
Signed-off-by: NSami Tolvanen <samitolvanen@google.com>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Commit 37c8a5fa ("kbuild: consolidate Devicetree dtb build rules")
moved the location of 'dtbs_install' target which caused dtbs to not be
installed when building debian package with 'bindeb-pkg' target. Update
the builddeb script to use the same logic that determines if there's a
'dtbs_install' target which is presence of the arch dts directory. Also,
use CONFIG_OF_EARLY_FLATTREE instead of CONFIG_OF as that's a better
indication of whether we are building dtbs.

This commit will also have the side effect of installing dtbs on any
arch that has dts files. Previously, it was dependent on whether the
arch defined 'dtbs_install'.

Fixes: 37c8a5fa ("kbuild: consolidate Devicetree dtb build rules")
Reported-by: NNuno Gonçalves <nunojpg@gmail.com>
Signed-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

This reverts commit 6147b1cf.

The reverted patch results in attempted write access to the source
repository, even if that repository is mounted read-only.

Output from "strace git status -uno --porcelain":

getcwd("/tmp/linux-test", 129)          = 16
open("/tmp/linux-test/.git/index.lock", O_RDWR|O_CREAT|O_EXCL|O_CLOEXEC, 0666) =
	-1 EROFS (Read-only file system)

While git appears to be able to handle this situation, a monitored
build environment (such as the one used for Chrome OS kernel builds)
may detect it and bail out with an access violation error. On top of
that, the attempted write access suggests that git _will_ write to the
file even if a build output directory is specified. Users may have the
reasonable expectation that the source repository remains untouched in
that situation.

Fixes: 6147b1cf ("scripts/setlocalversion: git: Make -dirty check more robust"
Cc: Genki Sky <sky@genki.is>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Reviewed-by: NBrian Norris <briannorris@chromium.org>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Since commit b41d920a ("kbuild: deb-pkg: split generating packaging
and build"), the build version of the kernel contained in a deb package
is too low by 1.

Prior to the bad commit, the kernel was built first, then the number
in .version file was read out, and written into the debian control file.

Now, the debian control file is created before the kernel is actually
compiled, which is causing the version number mismatch.

Let the mkdebian script pass KBUILD_BUILD_VERSION=${revision} to require
the build system to use the specified version number.

Fixes: b41d920a ("kbuild: deb-pkg: split generating packaging and build")
Reported-by: NDoug Smythies <dsmythies@telus.net>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: NDoug Smythies <dsmythies@telus.net>

The current SED_CONFIG_EXP could match to comment lines in config
fragment files, especially when CONFIG_PREFIX_ is empty. For example,
Buildroot uses empty prefixing; starting symbols with BR2_ is just
convention.

Make the sed expression more robust against false positives from
comment lines. The new sed expression matches to only valid patterns.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NPetr Vorel <petr.vorel@gmail.com>
Reviewed-by: NArnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

Ard Biesheuvel reports bindeb-pkg with O= option is broken in the
following way:

  ...
    LD [M]  sound/soc/rockchip/snd-soc-rk3399-gru-sound.ko
    LD [M]  sound/soc/rockchip/snd-soc-rockchip-pcm.ko
    LD [M]  sound/soc/rockchip/snd-soc-rockchip-rt5645.ko
    LD [M]  sound/soc/rockchip/snd-soc-rockchip-spdif.ko
    LD [M]  sound/soc/sh/rcar/snd-soc-rcar.ko
   fakeroot -u debian/rules binary
  make KERNELRELEASE=4.19.0-12677-g19beffaf7a99-dirty ARCH=arm64 KBUILD_SRC= intdeb-pkg
  /bin/bash /home/ard/linux/scripts/package/builddeb
  Makefile:600: include/config/auto.conf: No such file or directory
  ***
  *** Configuration file ".config" not found!
  ***
  *** Please run some configurator (e.g. "make oldconfig" or
  *** "make menuconfig" or "make xconfig").
  ***
  make[12]: *** [syncconfig] Error 1
  make[11]: *** [syncconfig] Error 2
  make[10]: *** [include/config/auto.conf] Error 2
  make[9]: *** [__sub-make] Error 2
  ...

Prior to commit 80463f1b ("kbuild: add --include-dir flag only
for out-of-tree build"), both srctree and objtree were added to
--include-dir redundantly, and the wrong code '$MAKE image_name'
was working by relying on that. Now, the potential issue that had
previously been hidden just showed up.

'$MAKE image_name' recurses to the generated $(objtree)/Makefile and
ends up with running in srctree, which is incorrect. It should be
invoked with '-f $srctree/Makefile' (or KBUILD_SRC=) to be executed
in objtree.

Fixes: 80463f1b ("kbuild: add --include-dir flag only for out-of-tree build")
Reported-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>

Zhenzhong Duan reported that running 'make O=/build/kernel binrpm-pkg'
failed with the following errors:

  Running 'make O=/build/kernel binrpm-pkg' failed with below two errors.

  Makefile:600: include/config/auto.conf: No such file or directory

  + cp make -C /mnt/root/kernel O=/build/kernel image_name make -f
  /mnt/root/kernel/Makefile ...
  cp: invalid option -- 'C'
  Try 'cp --help' for more information.

Prior to commit 80463f1b ("kbuild: add --include-dir flag only
for out-of-tree build"), both srctree and objtree were added to
--include-dir redundantly, and the wrong code 'make image_name'
was working by relying on that. Now, the potential issue that had
previously been hidden just showed up.

'make image_name' recurses to the generated $(objtree)/Makefile and
ends up with running in srctree, which is incorrect. It should be
invoked with '-f $srctree/Makefile' (or KBUILD_SRC=) to be executed
in objtree.

Fixes: 80463f1b ("kbuild: add --include-dir flag only for out-of-tree build")
Reported-by: NZhenzhong Duan <zhenzhong.duan@oracle.com>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

There is one more user of $(cc-name) in the top Makefile. It is supposed
to detect Clang before invoking Kconfig, so it should still be there
in the $(shell ...) form. All the other users of $(cc-name) have been
replaced with $(CONFIG_CC_IS_CLANG). Hence, scripts/Kbuild.include does
not need to define cc-name any more.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Evaluating cc-name invokes the compiler every time even when you are
not compiling anything, like 'make help'. This is not efficient.

The compiler type has been already detected in the Kconfig stage.
Use CONFIG_CC_IS_CLANG, instead.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Paul Burton <paul.burton@mips.com> (MIPS)
Acked-by: NJoel Stanley <joel@jms.id.au>

with CONFIG_ environment variable.

merge_config.sh uses CONFIG_ which is used in kernel and other projects.
There are some projects which use kconfig with different prefixes (e.g.
buildroot: BR2_ prefix). CONFIG_ variable is already used for this
purpose in kconfig binary (scripts/kconfig/lkc.h), let's use the same
rule for in merge_config.sh.
Suggested-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NPetr Vorel <petr.vorel@gmail.com>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

The last user of cc-fullversion was removed by commit f2910f0e
("powerpc: remove old GCC version checks").
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

As commit 911a91c3 ("kconfig: rename silentoldconfig to
syncconfig") announced, it is time for the removal.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

As commit 312ee687 ("kconfig: announce removal of oldnoconfig if
used") announced, it is time for the removal.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

This warning was there to avoid the use of 0bxxx values as they are not
supported by gcc prior to v4.3

Since cafa0010 ("Raise the minimum required gcc version to 4.6"),
it's not an issue anymore and using such values can increase readability
of code.

Joe said:

: Seems sensible as the other compilers also support binary literals from
: relatively old versions.
: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3472.pdf
: https://software.intel.com/en-us/articles/c14-features-supported-by-intel-c-compiler

Link: http://lkml.kernel.org/r/392eeae782302ee8812a3c932a602035deed1609.1535351453.git.christophe.leroy@c-s.frSigned-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Create DEF_FIELD_ADDR_VAR as a more generic version of the DEF_FIELD_ADD
macro, allowing usage of a variable name other than the struct element name.
Also, sets DEF_FIELD_ADDR as a specific usage of DEF_FILD_ADDR_VAR in which
the var name is the same as the struct element name.
Then, makes use of DEF_FIELD_ADDR_VAR to create a variable of another name,
in order to avoid variable shadowing.
Signed-off-by: NLeonardo Bras <leobras.c@gmail.com>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Remove an unnecessary shadowed local variable (start).
It was used only once, with the same value it was started before
the if block.
Signed-off-by: NLeonardo Bras <leobras.c@gmail.com>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

In addition to DEFINE_HASHTABLE() add DECLARE_ variant.

Link: http://lkml.kernel.org/r/153683203215.13678.11468076350083405643.stgit@localhost.localdomainSigned-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Constantine Shulyupin <const@MakeLinux.com>
Cc: Arend van Spriel <arend.vanspriel@broadcom.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Joey Pabalinas <joeypabalinas@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

'ifeq ... else ifeq ... endif' notation is supported by GNU Make 3.81
or later, which is the requirement for building the kernel since
commit 37d69ee3 ("docs: bump minimal GNU Make version to 3.81").

Use it to improve the readability.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Since commit c8589d1e ("kbuild: handle multi-objs dependency
appropriately"), $^ really represents all the prerequisite of the
composite object being built.

Hence, $(filter %.o,$^) contains all the objects to link together,
which is much simpler than link_multi_deps calculation.

Please note $(filter-out FORCE,$^) does not work here. When a single
object module is turned into a multi object module, $^ will contain
header files that were previously included for building the single
object, and recorded in the .*.cmd file. To filter out such headers,
$(filter %.o,$^) should be used here.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Blackfin and metag were the only architectures that prefix symbols with
an underscore. They were removed by commit 4ba66a97 ("arch: remove
blackfin port"), commit bb6fb6df ("metag: Remove arch/metag/"),
respectively.

It is no longer necessary to handle <prefix> part of module device
table symbols.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Make declaration type determination more robust.

When scripts/kernel-doc is deciding if some kernel-doc notation
contains an enum, a struct, a union, a typedef, or a function,
it does a pattern match on the beginning of the string, looking
for a match with one of "struct", "union", "enum", or "typedef",
and otherwise defaults to a function declaration type.
However, if a function or a function-like macro has a name that
begins with "struct" (e.g., struct_size()), then kernel-doc
incorrectly decides that this is a struct declaration.

Fix this by looking for the declaration type keywords having an
ending word boundary (\b), so that "struct_size" will not match
a struct declaration.

I compared lots of html before/after output from core-api, driver-api,
and networking.  There were no differences in any of the files that
I checked.
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Acked-by: NJani Nikula <jani.nikula@intel.com>
Tested-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

As on x86-64 and other architectures, the boot kernel on parisc (vmlinuz
and bzImage) contains a full compressed copy of the final kernel
executable (vmlinux.bin.gz), which one should be able to extract with
the extract-vmlinux script.

But on parisc extracting the kernel with extract-vmlinux fails.
Currently the script first checks if the given file is an ELF file
(which is true on parisc) and if so returns it.  Thus on parisc we
unexpectedly get back the vmlinuz boot file instead of the uncompressed
vmlinux image.

This patch fixes this issue by reverting the logic. It now first tries
to find a compression signature in the given file and if that fails it
checks the file itself as fallback.
Signed-off-by: NHelge Deller <deller@gmx.de>

Now that Variable Length Arrays (VLAs) have been entirely removed[1]
from the kernel, enable the VLA warning globally. The only exceptions
to this are the KASan an UBSan tests which are explicitly checking that
VLAs trigger their respective tests.

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com

Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Airlie <airlied@linux.ie>
Cc: linux-kbuild@vger.kernel.org
Cc: intel-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: NKees Cook <keescook@chromium.org>

Assuming we never invoke the generated Makefile from outside of
the $(objtree) directory, $(CURDIR) points to the absolute path
of $(objtree).

BTW, 'lastword' is natively supported by GNU Make 3.81+, which
is the current requirement for building the kernel.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>