Add more types of lines that appear to be stack dumps that also include
hex lines that might otherwise be interpreted as commit IDs.

Link: http://lkml.kernel.org/r/ff00208289224f0ca4eaf4ff7c9c6e087dad0a63.camel@perches.com

Link: http://lkml.kernel.org/r/f7dc9727795db3802809a24162abe0b67e14123b.1563575364.git.joe@perches.comSigned-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I used the C comment style (/* ... */) for the flex and bison files
as in Kconfig (scripts/kconfig/{lexer.l,parser.y})
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Use the __section() shorthand. This avoids escaping double-quotes,
and improves the readability.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

This makes *.mod.c much more readable. I confirmed depmod still
produced the same modules.dep file.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Arnd Bergmann reported false-positive modpost warnings detected by his
randconfig testing of linux-next.

Actually, this happens under the combination of CONFIG_MODVERSIONS
and CONFIG_TRIM_UNUSED_KSYMS since commit 15bfc234 ("modpost:
check for static EXPORT_SYMBOL* functions").

For example, arch/arm/config/multi_v7_defconfig + CONFIG_MODVERSIONS
+ CONFIG_TRIM_UNUSED_KSYMS produces the following false-positives:

WARNING: "__lshrdi3" [vmlinux] is a static (unknown)
WARNING: "__ashrdi3" [vmlinux] is a static (unknown)
WARNING: "__aeabi_lasr" [vmlinux] is a static (unknown)
WARNING: "__aeabi_llsr" [vmlinux] is a static (unknown)
WARNING: "ftrace_set_clr_event" [vmlinux] is a static (unknown)
WARNING: "__muldi3" [vmlinux] is a static (unknown)
WARNING: "__aeabi_ulcmp" [vmlinux] is a static (unknown)
WARNING: "__ucmpdi2" [vmlinux] is a static (unknown)
WARNING: "__aeabi_lmul" [vmlinux] is a static (unknown)
WARNING: "__bswapsi2" [vmlinux] is a static (unknown)
WARNING: "__bswapdi2" [vmlinux] is a static (unknown)
WARNING: "__ashldi3" [vmlinux] is a static (unknown)
WARNING: "__aeabi_llsl" [vmlinux] is a static (unknown)

The root cause of the problem is not in the modpost, but in the
implementation of CONFIG_TRIM_UNUSED_KSYMS.

If there is at least one untrimmed symbol in the file, genksyms is
invoked to calculate CRC of *all* the exported symbols in that file
even if some of them have been trimmed due to no caller existing.

As a result, .tmp_*.ver files contain CRC of trimmed symbols, thus
unneeded, orphan __crc* symbols are added to objects. It had been
harmless until recently.

With commit 15bfc234 ("modpost: check for static EXPORT_SYMBOL*
functions"), it is now harmful because the bogus __crc* symbols make
modpost call sym_update_crc() to add the symbols to the hash table,
but there is no one that clears the ->is_static member.

I gave Fixes to the first commit that uncovered the issue, but the
potential problem has long existed since commit f2355416
("export.h: allow for per-symbol configurable EXPORT_SYMBOL()").

Fixes: 15bfc234 ("modpost: check for static EXPORT_SYMBOL* functions")
Reported-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: NArnd Bergmann <arnd@arndb.de>

A script that uses the '<module>.ns_deps' files generated by modpost to
automatically add the required symbol namespace dependencies to each
module.

Usage:
1) Move some symbols to a namespace with EXPORT_SYMBOL_NS() or define
   DEFAULT_SYMBOL_NAMESPACE
2) Run 'make' (or 'make modules') and get warnings about modules not
   importing that namespace.
3) Run 'make nsdeps' to automatically add required import statements
   to said modules.

This makes it easer for subsystem maintainers to introduce and maintain
symbol namespaces into their codebase.
Co-developed-by: NMartijn Coenen <maco@android.com>
Signed-off-by: NMartijn Coenen <maco@android.com>
Acked-by: NJulia Lawall <julia.lawall@lip6.fr>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NMatthias Maennich <maennich@google.com>
Signed-off-by: NJessica Yu <jeyu@kernel.org>

This patch adds an option to modpost to generate a <module>.ns_deps file
per module, containing the namespace dependencies for that module.

E.g. if the linked module my-module.ko would depend on the symbol
myfunc.MY_NS in the namespace MY_NS, the my-module.ns_deps file created
by modpost would contain the entry MY_NS to express the namespace
dependency of my-module imposed by using the symbol myfunc.

These files can subsequently be used by static analysis tools (like
coccinelle scripts) to address issues with missing namespace imports. A
later patch of this series will introduce such a script 'nsdeps' and a
corresponding make target to automatically add missing
MODULE_IMPORT_NS() definitions to the module's sources. For that it uses
the information provided in the generated .ns_deps files.
Co-developed-by: NMartijn Coenen <maco@android.com>
Signed-off-by: NMartijn Coenen <maco@android.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NMatthias Maennich <maennich@google.com>
Signed-off-by: NJessica Yu <jeyu@kernel.org>

Add support for symbols that are exported into namespaces. For that,
extract any namespace suffix from the symbol name. In addition, emit a
warning whenever a module refers to an exported symbol without
explicitly importing the namespace that it is defined in. This patch
consistently adds the namespace suffix to symbol names exported into
Module.symvers.

Example warning emitted by modpost in case of the above violation:

 WARNING: module ums-usbat uses symbol usb_stor_resume from namespace
 USB_STORAGE, but does not import it.
Co-developed-by: NMartijn Coenen <maco@android.com>
Signed-off-by: NMartijn Coenen <maco@android.com>
Reviewed-by: NJoel Fernandes (Google) <joel@joelfernandes.org>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NMatthias Maennich <maennich@google.com>
Signed-off-by: NJessica Yu <jeyu@kernel.org>

GCC and Clang have different policy for -Wunused-function; GCC does not
warn unused static inline functions at all whereas Clang does if they
are defined in source files instead of included headers although it has
been suppressed since commit abb2ea7d ("compiler, clang: suppress
warning for unused static inline functions").

We often miss to delete unused functions where 'static inline' is used
in *.c files since there is no tool to detect them. Unused code remains
until somebody notices. For example, commit 075ddd75 ("regulator:
core: remove unused rdev_get_supply()").

Let's remove __maybe_unused from the inline macro to allow Clang to
start finding unused static inline functions. For now, we do this only
for W=1 build since it is not a good idea to sprinkle warnings for the
normal build (e.g. 35 warnings for arch/x86/configs/x86_64_defconfig).

My initial attempt was to add -Wno-unused-function for no W= build
(https://lore.kernel.org/patchwork/patch/1120594/)

Nathan Chancellor pointed out that would weaken Clang's checks since
we would no longer get -Wunused-function without W=1. It is true GCC
would catch unused static non-inline functions, but it would weaken
Clang as a standalone compiler, at least.

Hence, here is a counter implementation. The current problem is, W=...
only controls compiler flags, which are globally effective. There is
no way to address only 'static inline' functions.

This commit defines KBUILD_EXTRA_WARN[123] corresponding to W=[123].
When KBUILD_EXTRA_WARN1 is defined, __maybe_unused is omitted from
the 'inline' macro.

The new macro __inline_maybe_unused makes the code a bit uglier, so I
hope we can remove it entirely after fixing most of the warnings.

If you contribute to code clean-up, please run "make CC=clang W=1"
and check -Wunused-function warnings. You will find lots of unused
functions.

Some of them are false-positives because the call-sites are disabled
by #ifdef. I do not like to abuse the inline keyword for suppressing
unused-function warnings because it is intended to be a hint for the
compiler optimization. I prefer #ifdef around the definition, or
__maybe_unused if #ifdef would make the code too ugly.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NNathan Chancellor <natechancellor@gmail.com>
Tested-by: NNathan Chancellor <natechancellor@gmail.com>

${@:2} is BASH-specific extension, which makes link-vmlinux.sh rely on
BASH. Use shift and ${@} instead to fix this issue.
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Fixes: 341dfcf8 ("btf: expose BTF info through sysfs")
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Acked-by: NYonghong Song <yhs@fb.com>
Reviewed-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

KBUILD_ENABLE_EXTRA_GCC_CHECKS started as a switch to add extra warning
options for GCC, but now it is a historical misnomer since we use it
also for Clang, DTC, and even kernel-doc.

Rename it to more sensible, shorter KBUILD_EXTRA_WARN.

For the backward compatibility, KBUILD_ENABLE_EXTRA_GCC_CHECKS is still
supported (but not advertised in the documentation).

I also fixed up 'make help', and updated the documentation.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NNathan Chancellor <natechancellor@gmail.com>
Reviewed-by: NNick Desaulniers <ndesaulniers@google.com>
Reviewed-by: NSedat Dilek <sedat.dilek@gmail.com>

Instead of the warning-[123] magic, let's accumulate compiler options
to KBUILD_CFLAGS directly as the top Makefile does. I think this makes
it easier to understand what is going on in this file.

This commit slightly changes the behavior, I think all of which are OK.

[1] Currently, cc-option calls are needlessly evaluated. For example,
      warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
    needs evaluating only when W=3, but it is actually evaluated for
    W=1, W=2 as well. With this commit, only relevant cc-option calls
    will be evaluated. This is a slight optimization.

[2] Currently, unsupported level like W=4 is checked by:
      $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown)
    This will no longer be checked, but I do not think it is a big
    deal.

[3] Currently, 4 Clang warnings (Winitializer-overrides, Wformat,
    Wsign-compare, Wformat-zero-length) are shown by any of W=1, W=2,
    and W=3. With this commit, they will be warned only by W=1. I
    think this is a more correct behavior since each warning belongs
    to only one group.

For understanding this commit correctly:

We have 3 warning groups, W=1, W=2, and W=3. You may think W=3 has a
higher level than W=1, but they are actually independent. If you like,
you can combine them like W=13. To enable all the warnings, you can
pass W=123. It is shown by 'make help', but not noticed much. Since we
support W= combination, there should not exist intersection among the
three groups. If we enable Winitializer-overrides for W=1, we do not
need to for W=2 or W=3. This is the reason why I think the change [3]
makes sense.

The documentation says -Winitializer-overrides is enabled by default.
(https://clang.llvm.org/docs/DiagnosticsReference.html#winitializer-overrides)
We negate it by passing -Wno-initializer-overrides for the normal
build, but we do not do that for W=1. This means, W=1 effectively
enables -Winitializer-overrides by the clang's default. The same for
the other three.

Add comments in case people are confused with the code.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NNathan Chancellor <natechancellor@gmail.com>
Tested-by: NSedat Dilek <sedat.dilek@gmail.com>
Acked-by: NNick Desaulniers <ndesaulniers@google.com>
Acked-by: NMiguel Ojeda <miguel.ojeda.sandonis@gmail.com>

When do coccicheck, I get this error:

spatch -D report --no-show-diff --very-quiet --cocci-file
./scripts/coccinelle/api/platform_get_irq.cocci --include-headers
--dir . -I ./arch/x86/include -I ./arch/x86/include/generated -I ./include
 -I ./arch/x86/include/uapi -I ./arch/x86/include/generated/uapi
 -I ./include/uapi -I ./include/generated/uapi
 --include ./include/linux/kconfig.h --jobs 192 --chunksize 1
minus: parse error:
  File "./scripts/coccinelle/api/platform_get_irq.cocci", line 24, column 9, charpos = 355
  around = '\(',
  whole content = if ( ret \( < \| <= \) 0 )

In commit e56476897448 ("fpga: Remove dev_err() usage
after platform_get_irq()") log, I found the semantic patch,
it fix this issue.

Fixes: 98051ba2 ("coccinelle: Add script to check for platform_get_irq() excessive prints")
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Reviewed-by: NStephen Boyd <swboyd@chromium.org>
Acked-by: NJulia Lawall <julia.lawall@lip6.fr>
Link: https://lore.kernel.org/r/20190906033006.17616-1-yuehaibing@huawei.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The merge_config.sh script verifies that all the config options have
their expected value in the resulting file and prints any issues as
warnings.  These checks aren't intended to be treated as errors given
the current implementation.  However, since "set -e" was added, if the
grep command to look for a config option does not find it the script
will then abort prematurely.

Handle the case where the grep exit status is non-zero by setting
ACTUAL_VAL to an empty string to restore previous functionality.

Fixes: cdfca821 ("merge_config.sh: Check error codes from make")
Signed-off-by: NGuillaume Tucker <guillaume.tucker@collabora.com>
Acked-by: NJon Hunter <jonathanh@nvidia.com>
Tested-by: NJon Hunter <jonathanh@nvidia.com>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Kbuild provides per-file compiler flag addition/removal:

  CFLAGS_<basetarget>.o
  CFLAGS_REMOVE_<basetarget>.o
  AFLAGS_<basetarget>.o
  AFLAGS_REMOVE_<basetarget>.o
  CPPFLAGS_<basetarget>.lds
  HOSTCFLAGS_<basetarget>.o
  HOSTCXXFLAGS_<basetarget>.o

The <basetarget> is the filename of the target with its directory and
suffix stripped.

This syntax comes into a trouble when two files with the same basename
appear in one Makefile, for example:

  obj-y += foo.o
  obj-y += dir/foo.o
  CFLAGS_foo.o := <some-flags>

Here, the <some-flags> applies to both foo.o and dir/foo.o

The real world problem is:

  scripts/kconfig/util.c
  scripts/kconfig/lxdialog/util.c

Both files are compiled into scripts/kconfig/mconf, but only the
latter should be given with the ncurses flags.

It is more sensible to use the relative path to the Makefile, like this:

  obj-y += foo.o
  CFLAGS_foo.o := <some-flags>
  obj-y += dir/foo.o
  CFLAGS_dir/foo.o := <other-flags>

At first, I attempted to replace $(basetarget) with $*. The $* variable
is replaced with the stem ('%') part in a pattern rule. This works with
most of cases, but does not for explicit rules.

For example, arch/ia64/lib/Makefile reuses rule_as_o_S in its own
explicit rules, so $* will be empty, resulting in ignoring the per-file
AFLAGS.

I introduced a new variable, target-stem, which can be used also from
explicit rules.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NMarc Zyngier <maz@kernel.org>

Add NOFAIL check for the strndup call, because the function
allocates memory and can return NULL. All calls to strdup in
modpost are checked with NOFAIL.
Signed-off-by: NDenis Efremov <efremov@linux.com>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Since guid_t is the recommended data type for UUIDs in
kernel (and I guess uuid_le is meant to be ultimately
replaced with it), it should be made available here as
well.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

CONFIG_SHELL falls back to sh when bash is not installed on the system,
but nobody is testing such a case since bash is usually installed.
So, shell scripts invoked by CONFIG_SHELL are only tested with bash.

It makes it difficult to test whether the hashbang #!/bin/sh is real.
For example, #!/bin/sh in arch/powerpc/kernel/prom_init_check.sh is
false. (I fixed it up)

Besides, some shell scripts invoked by CONFIG_SHELL use bash-extension
and #!/bin/bash is specified as the hashbang, while CONFIG_SHELL may
not always be set to bash.

Probably, the right thing to do is to introduce BASH, which is bash by
default, and always set CONFIG_SHELL to sh. Replace $(CONFIG_SHELL)
with $(BASH) for bash scripts.

If somebody tries to add bash-extension to a #!/bin/sh script, it will
be caught in testing because /bin/sh is a symlink to dash on some major
distributions.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

cleanup() mostly frees/unmaps the malloc'd/privately-mapped
copy of the ELF file recordmcount is working on, which is
set up in mmap_file(). It also deals with positioning within
the pseduo prive-mapping of the file and appending to the ELF
file.

Split into two steps:
	mmap_cleanup() for the mapping itself
	file_append_cleanup() for allocations storing the
		appended ELF data.

Also, move the global variable initializations out of the main,
per-object-file loop and nearer to the alloc/init (mmap_file())
and two cleanup functions so we can more clearly see how they're
related.

Link: http://lkml.kernel.org/r/2a387ac86d133d22c68f57b9933c32bab1d09a2d.1564596289.git.mhelsley@vmware.comSigned-off-by: NMatt Helsley <mhelsley@vmware.com>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>

Redundant cleanup calls were introduced when transitioning from
the old error/success handling via setjmp/longjmp -- the longjmp
ensured the cleanup() call only happened once but replacing
the success_file()/fail_file() calls with cleanup() meant that
multiple cleanup() calls can happen as we return from function
calls.

In do_file(), looking just before and after the "goto out" jumps we
can see that multiple cleanups() are being performed. We remove
cleanup() calls from the nested functions because it makes the code
easier to review -- the resources being cleaned up are generally
allocated and initialized in the callers so freeing them there
makes more sense.

Other redundant cleanup() calls:

mmap_file() is only called from do_file() and, if mmap_file() fails,
then we goto out and do cleanup() there too.

write_file() is only called from do_file() and do_file()
calls cleanup() unconditionally after returning from write_file()
therefore the cleanup() calls in write_file() are not necessary.

find_secsym_ndx(), called from do_func()'s for-loop, when we are
cleaning up here it's obvious that we break out of the loop and
do another cleanup().

__has_rel_mcount() is called from two parts of do_func()
and calls cleanup(). In theory we move them into do_func(), however
these in turn prove redundant so another simplification step
removes them as well.

Link: http://lkml.kernel.org/r/de197e17fc5426623a847ea7cf3a1560a7402a4b.1564596289.git.mhelsley@vmware.comSigned-off-by: NMatt Helsley <mhelsley@vmware.com>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>

Fix up the whitespace irregularity in the ELF switch
blocks.

Swapping the initial value of gpfx allows us to
simplify all but one of the one-line switch cases even
further.

Link: http://lkml.kernel.org/r/647f21f43723d3e831cedd3238c893db03eea6f0.1564596289.git.mhelsley@vmware.comSigned-off-by: NMatt Helsley <mhelsley@vmware.com>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>

The uwrite() and ulseek() functions are formatted inconsistently
with the rest of the file and the kernel overall. While we're
making other changes here let's fix this.

Link: http://lkml.kernel.org/r/4c67698f734be9867a2aba7035fe0ce59e1e4423.1564596289.git.mhelsley@vmware.comSigned-off-by: NMatt Helsley <mhelsley@vmware.com>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>

Recordmcount uses setjmp/longjmp to manage control flow as
it reads and then writes the ELF file. This unusual control
flow is hard to follow and check in addition to being unlike
kernel coding style.

So we rewrite these paths to use regular return values to
indicate error/success. When an error or previously-completed object
file is found we return an error code following kernel
coding conventions -- negative error values and 0 for success when
we're not returning a pointer. We return NULL for those that fail
and return non-NULL pointers otherwise.

One oddity is already_has_rel_mcount -- there we use pointer comparison
rather than string comparison to differentiate between
previously-processed object files and returning the name of a text
section.

Link: http://lkml.kernel.org/r/8ba8633d4afe444931f363c8d924bf9565b89a86.1564596289.git.mhelsley@vmware.comSigned-off-by: NMatt Helsley <mhelsley@vmware.com>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>

uwrite() works within the pseudo-mapping and extends it as necessary
without needing the file descriptor (fd) parameter passed to it.
Similarly, ulseek() doesn't need its fd parameter. These parameters
were only added because the functions bear a conceptual resemblance
to write() and lseek(). Worse, they obscure the fact that at the time
uwrite() and ulseek() are called fd_map is not a valid file descriptor.

Remove the unused file descriptor parameters that make it look like
fd_map is still valid.

Link: http://lkml.kernel.org/r/2a136e820ee208469d375265c7b8eb28570749a0.1563992889.git.mhelsley@vmware.comSigned-off-by: NMatt Helsley <mhelsley@vmware.com>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>

uread() is only used to initialize the ELF file's pseudo
private-memory mapping while uwrite() and ulseek() work within
the pseudo-mapping and extend it as necessary.  Thus it is not
a complementary function to uwrite() and ulseek(). It also makes
no sense to do cleanups inside uread() when its only caller,
mmap_file(), is doing the relevant allocations and associated
initializations.

Therefore it's clearer to use a plain read() call to initialize the
data in mmap_file() and remove uread().

Link: http://lkml.kernel.org/r/31a87c22b19150cec1c8dc800c8b0873a2741703.1563992889.git.mhelsley@vmware.comSigned-off-by: NMatt Helsley <mhelsley@vmware.com>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>

The strcmp is unnecessary since .text is already accepted as a
prefix in the strncmp().

Link: http://lkml.kernel.org/r/358e590b49adbe4185e161a8b364e323f3d52857.1563992889.git.mhelsley@vmware.comSigned-off-by: NMatt Helsley <mhelsley@vmware.com>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>

Remove some variables.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

This '+' was added a long time ago:

| commit c23e6bf05f7802e92fd3da69a1ed35e56f9c85bb (HEAD)
| Author: Kai Germaschewski <kai@tp1.ruhr-uni-bochum.de>
| Date:   Mon Oct 28 01:16:34 2002 -0600
|
|     kbuild: Fix a "make -j<N>" warning
|
| diff --git a/scripts/Makefile.clean b/scripts/Makefile.clean
| index 2c843e0380bc..e7c392fd5788 100644
| --- a/scripts/Makefile.clean
| +++ b/scripts/Makefile.clean
| @@ -42,7 +42,7 @@ quiet_cmd_clean = CLEAN   $(obj)
|
|  __clean: $(subdir-ymn)
|  ifneq ($(strip $(__clean-files) $(clean-rule)),)
| -        $(call cmd,clean)
| +        +$(call cmd,clean)
|  else
|          @:
|  endif

At that time, cmd_clean contained $(clean-rule), which was able to
invoke sub-make. That was why cleaning with the -j option showed:
warning: jobserver unavailable: using -j1.  Add '+' to parent make rule.

It is not the case any more; cmd_clean now just runs the 'rm' command.
The '+' marker is pointless.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

The only the difference between clean-files and clean-dirs is the -r
option passed to the 'rm' command.

You can always pass -r, and then remove the clean-dirs syntax.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Both relative path and absolute path have pros and cons. For example,
we can move the source and objtree around together by using the
relative path to the source tree.

Do not force the absolute path to the source tree. If you prefer the
absolute path, you can specify KBUILD_ABS_SRCTREE=1.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Kbuild descends into scripts/basic/ even before the Kconfig.
I do not expect any other host programs added to this Makefile.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

scripts/package/Makefile does not use $(obj) or $(src) at all.
It actually generates files and directories in the top of $(objtree).
I do not see much sense in descending into scripts/package/.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

These are not real targets. Adding them to PHONY is preferred.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

I am not a big fan of the $(objtree)/ hack for clean-files/clean-dirs.

These are created in the top of $(objtree), so let's clean them up
from the top Makefile.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

When we execute make after merging the configurations we ignore any
errors it produces causing whatever is running merge_config.sh to be
unaware of any failures.  This issue was noticed by Guillaume Tucker
while looking at problems with testing of clang only builds in KernelCI
which caused Kbuild to be unable to find a working host compiler.

This implementation was suggested by Yamada-san.
Suggested-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reported-by: NGuillaume Tucker <guillaume.tucker@collabora.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Makefile.lib is included by Makefile.modfinal as well as Makefile.build.

Move modkern_cflags to Makefile.lib in order to simplify cmd_cc_o_c
in Makefile.modfinal. Move modkern_cflags as well for consistency.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Add CONFIG_ASM_MODVERSIONS. This allows to remove one if-conditional
nesting in scripts/Makefile.build.

scripts/Makefile.build is run every time Kbuild descends into a
sub-directory. So, I want to avoid $(wildcard ...) evaluation
where possible although computing $(wildcard ...) is so cheap that
it may not make measurable performance difference.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>

I think splitting the modpost and linking modules into separate
Makefiles will be useful especially when more complex build steps
come in. The main motivation of this commit is to integrate the
proposed klp-convert feature cleanly.

I moved the logging 'Building modules, stage 2.' to Makefile.modpost
to avoid the code duplication although I do not know whether or not
this message is needed in the first place.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Building s390 kernel with CONFIG_DEBUG_INFO_BTF fails, because
CONFIG_OUTPUT_FORMAT is not defined. As a matter of fact, this variable
appears to be x86-only, so other arches might be affected as well.

Fix by obtaining this value from objdump output, just like it's already
done for bin_arch. The exact objdump invocation is "inspired" by
arch/powerpc/boot/wrapper.

Also, use LANG=C for the existing bin_arch objdump invocation to avoid
potential build issues on systems with non-English locale.

Fixes: 341dfcf8 ("btf: expose BTF info through sysfs")
Signed-off-by: NIlya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Currently, the timestamp of module linker scripts are not checked.
Add them to the dependency of modules so they are correctly rebuilt.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>