The previous commit made 'MAKEFLAGS += -rR' effective in the top
Makefile regardless of O= option, GNU Make versions.
The top Makefile does not need to cancel implicit rules for makefiles.
There is still one place where an empty rule is useful. Since -rR is
effective only after sub-make, GNU Make would try implicit rules to
update the top Makefile. Although it is not a big overhead, cancel it
just in case.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Adding -rR to MAKEFLAGS is important because we do not want to
be bothered by built-in implicit rules or variables.
One problem that used to exist in older GNU Make versions is
MAKEFLAGS += -rR
... does not become effective in the current Makefile. When you are
building with O= option, it becomes effective in the top Makefile
since it recurses via 'sub-make' target. Otherwise, the top Makefile
tries implicit rules. That is why we explicitly add empty rules for
Makefiles, but we often miss to do that.
In fact, adding -d option to older GNU Make versions shows it is
trying a bunch of implicit pattern rules.
Considering target file `scripts/Makefile.kcov'.
Looking for an implicit rule for `scripts/Makefile.kcov'.
Trying pattern rule with stem `Makefile.kcov'.
Trying implicit prerequisite `scripts/Makefile.kcov.o'.
Trying pattern rule with stem `Makefile.kcov'.
Trying implicit prerequisite `scripts/Makefile.kcov.c'.
Trying pattern rule with stem `Makefile.kcov'.
Trying implicit prerequisite `scripts/Makefile.kcov.cc'.
Trying pattern rule with stem `Makefile.kcov'.
Trying implicit prerequisite `scripts/Makefile.kcov.C'.
...
This issue was fixed by GNU Make commit 58dae243526b ("[Savannah #20501]
Handle adding -r/-R to MAKEFLAGS in the makefile"). So, it is no longer
a problem if you use GNU Make 4.0 or later. However, older versions are
still widely used.
So, I decided to patch the kernel Makefile to invoke sub-make regardless
of O= option. This will allow further cleanups.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Since -Wmaybe-uninitialized was introduced by GCC 4.7, we have patched
various false positives:
- commit e74fc973b6 ("Turn off -Wmaybe-uninitialized when building
with -Os") turned off this option for -Os.
- commit 815eb71e71 ("Kbuild: disable 'maybe-uninitialized' warning
for CONFIG_PROFILE_ALL_BRANCHES") turned off this option for
CONFIG_PROFILE_ALL_BRANCHES
- commit a76bcf557e ("Kbuild: enable -Wmaybe-uninitialized warning
for "make W=1"") turned off this option for GCC < 4.9
Arnd provided more explanation in https://lkml.org/lkml/2017/3/14/903
I think this looks better by shifting the logic from Makefile to Kconfig.
Link: https://github.com/ClangBuiltLinux/linux/issues/350
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
The genksyms source was integrated into the kernel tree in 2003.
I do not expect anybody still using the external /sbin/genksyms.
Kbuild does not need to provide the ability to override GENKSYMS.
Let's remove the GENKSYMS variable, and use the hardcoded path.
Since it occurred in the pre-git era, I attached the commit message
in case somebody is interested in the historical background.
| Author: Kai Germaschewski <kai@tp1.ruhr-uni-bochum.de>
| Date: Wed Feb 19 04:17:28 2003 -0600
|
| kbuild: [PATCH] put genksyms in scripts dir
|
| This puts genksyms into scripts/genksyms/.
|
| genksyms used to be maintained externally, though the only possible user
| was the kernel build. Moving it into the kernel sources makes it easier to
| keep it uptodate, like for example updating it to generate linker scripts
| directly instead of postprocessing the generated header file fragments
| with sed, as we do currently.
|
| Also, genksyms does not handle __typeof__, which needs to be fixed since
| some of the exported symbol in the kernel are defined using __typeof__.
|
| (Rusty Russell/me)
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
It is weird to create gdb stuff as a side-effect of vmlinux.
Move it to a more relevant place.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Currently, Kbuild descends from scripts/Makefile to scripts/gdb/Makefile
just for creating symbolic links, but it does not need to do it so early.
Merge the two descending paths to simplify the code.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
scripts/gdb/linux/constants.py is never used in the kernel build
process. There is no good reason to create it so early.
Get it out of the 'prepare' stage.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Commit 06300b21f4 ("kbuild: support building individual files for
external modules") introduced the '/' target. It works only for
external modules to build all .o files, but skip the modpost stage.
However, 'make /' looks a bit weird to me. 'make ./' is more sensible
if you want to build all objects under the current directory, and it
works as expected.
Let's change '/' into a phony target that is an alias of './', but
I may feel like deprecating it in the future.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
It is fine to set KBUILD_MODULES=1 when CONFIG_MODULES is disabled.
It is actually how "make allnoconfig all" works.
On the other hand, KBUILD_MODULES=1 is unneeded for the %.ko pattern.
It is just a matter of whether modules.order is generated or not.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
This causes an issue when trying to build with `make LD=ld.lld` if
ld.lld and the rest of your cross tools aren't in the same directory
(ex. /usr/local/bin) (as is the case for Android's build system), as the
GCC_TOOLCHAIN_DIR then gets set based on `which $(LD)` which will point
where LLVM tools are, not GCC/binutils tools are located.
Instead, select the GCC_TOOLCHAIN_DIR based on another tool provided by
binutils for which LLVM does not provide a substitute for, such as
elfedit.
Fixes: 785f11aa59 ("kbuild: Add better clang cross build support")
Link: https://github.com/ClangBuiltLinux/linux/issues/341
Suggested-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
When compiling into output directory using O=, many files
created under KBUILD_OUTPUT that git considers
as new ones; git clients, ex. "git gui" lists it, and it clutters
file list making it difficult to see what was really changed
Generate .gitignore in output directory that ignores all
its content
Signed-off-by: Vladimir Kondratiev <vladimir.kondratiev@linux.intel.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
There is no build order among the following:
prepare3
outputmakefile
asm-generic
$(version_h)
$(autoksyms_h)
include/generated/utsrelease.h
It is meaningless to insert the prepare2 target between the first
three and the last three.
The comment says, "prepare2 creates a makefile if using a separate
output directory." Let me explain it more precisely. The prepare
targets cannot be executed without the .config file. Because the
configuration targets depend on the outputmakefile target, the
generated makefile is already there before the parepare2 is run.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The top Makefile does not need to export KBUILD_VMLINUX_INIT and
KBUILD_VMLINUX_MAIN separately.
Put every built-in.a into KBUILD_VMLINUX_OBJS. The order of
$(head-y), $(init-y), $(core-y), ... is still retained.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Currently, the 'firmware' directory only contains a single Makefile
to embed extra firmware into the kernel.
Move it to the more relevant place.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit c3ff2a5193 ("powerpc/32: add stack protector support")
caused kernel panic on PowerPC when an external module is used with
CONFIG_STACKPROTECTOR because the 'prepare' target was not executed
for the external module build.
Commit e07db28eea ("kbuild: fix single target build for external
module") turned it into a build error because the 'prepare' target is
now executed but the 'prepare0' target is missing for the external
module build.
External module on arm/arm64 with CONFIG_STACKPROTECTOR_PER_TASK is
also broken in the same way.
Move 'PHONY += prepare0' to the common place. GNU Make is fine with
missing rule for phony targets. I also removed the comment which is
wrong irrespective of this commit.
I minimize the change so it can be easily backported to 4.20.x
To fix v4.20, please backport e07db28eea ("kbuild: fix single target
build for external module"), and then this commit.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=201891
Fixes: e07db28eea ("kbuild: fix single target build for external module")
Fixes: c3ff2a5193 ("powerpc/32: add stack protector support")
Fixes: 189af46571 ("ARM: smp: add support for per-task stack canaries")
Fixes: 0a1213fa74 ("arm64: enable per-task stack canaries")
Cc: linux-stable <stable@vger.kernel.org> # v4.20
Reported-by: Samuel Holland <samuel@sholland.org>
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
You do not have to use define ... endef for filechk_* rules.
For simple cases, the use of assignment looks cleaner, IMHO.
I updated the usage for scripts/Kbuild.include in case somebody
misunderstands the 'define ... endif' is the requirement.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
filechk_* rules often consist of multiple 'echo' lines. They must be
surrounded with { } or ( ) to work correctly. Otherwise, only the
string from the last 'echo' would be written into the target.
Let's take care of that in the 'filechk' in scripts/Kbuild.include
to clean up filechk_* rules.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Currently, CONFIG_JUMP_LABEL just means "I _want_ to use jump label".
The jump label is controlled by HAVE_JUMP_LABEL, which is defined
like this:
#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL)
# define HAVE_JUMP_LABEL
#endif
We can improve this by testing 'asm goto' support in Kconfig, then
make JUMP_LABEL depend on CC_HAS_ASM_GOTO.
Ugly #ifdef HAVE_JUMP_LABEL will go away, and CONFIG_JUMP_LABEL will
match to the real kernel capability.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Pull Devicetree updates from Rob Herring:
"The biggest highlight here is the start of using json-schema for DT
bindings. Being able to validate bindings has been discussed for years
with little progress.
- Initial support for DT bindings using json-schema language. This is
the start of converting DT bindings from free-form text to a
structured format.
- Reworking of initrd address initialization. This moves to using the
phys address instead of virt addr in the DT parsing code. This
rework was motivated by CONFIG_DEV_BLK_INITRD causing unnecessary
rebuilding of lots of files.
- Fix stale phandle entries in phandle cache
- DT overlay validation improvements. This exposed several memory
leak bugs which have been fixed.
- Use node name and device_type helper functions in DT code
- Last remaining conversions to using %pOFn printk specifier instead
of device_node.name directly
- Create new common RTC binding doc and move all trivial RTC devices
out of trivial-devices.txt.
- New bindings for Freescale MAG3110 magnetometer, Cadence Sierra
PHY, and Xen shared memory
- Update dtc to upstream version v1.4.7-57-gf267e674d145"
* tag 'devicetree-for-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (68 commits)
of: __of_detach_node() - remove node from phandle cache
of: of_node_get()/of_node_put() nodes held in phandle cache
gpio-omap.txt: add reg and interrupts properties
dt-bindings: mrvl,intc: fix a trivial typo
dt-bindings: iio: magnetometer: add dt-bindings for freescale mag3110
dt-bindings: Convert trivial-devices.txt to json-schema
dt-bindings: arm: mrvl: amend Browstone compatible string
dt-bindings: arm: Convert Tegra board/soc bindings to json-schema
dt-bindings: arm: Convert ZTE board/soc bindings to json-schema
dt-bindings: arm: Add missing Xilinx boards
dt-bindings: arm: Convert Xilinx board/soc bindings to json-schema
dt-bindings: arm: Convert VIA board/soc bindings to json-schema
dt-bindings: arm: Convert ST STi board/soc bindings to json-schema
dt-bindings: arm: Convert SPEAr board/soc bindings to json-schema
dt-bindings: arm: Convert CSR SiRF board/soc bindings to json-schema
dt-bindings: arm: Convert QCom board/soc bindings to json-schema
dt-bindings: arm: Convert TI nspire board/soc bindings to json-schema
dt-bindings: arm: Convert TI davinci board/soc bindings to json-schema
dt-bindings: arm: Convert Calxeda board/soc bindings to json-schema
dt-bindings: arm: Convert Altera board/soc bindings to json-schema
...
Pull x86 fixes from Ingo Molnar:
"The biggest part is a series of reverts for the macro based GCC
inlining workarounds. It caused regressions in distro build and other
kernel tooling environments, and the GCC project was very receptive to
fixing the underlying inliner weaknesses - so as time ran out we
decided to do a reasonably straightforward revert of the patches. The
plan is to rely on the 'asm inline' GCC 9 feature, which might be
backported to GCC 8 and could thus become reasonably widely available
on modern distros.
Other than those reverts, there's misc fixes from all around the
place.
I wish our final x86 pull request for v4.20 was smaller..."
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "kbuild/Makefile: Prepare for using macros in inline assembly code to work around asm() related GCC inlining bugs"
Revert "x86/objtool: Use asm macros to work around GCC inlining bugs"
Revert "x86/refcount: Work around GCC inlining bug"
Revert "x86/alternatives: Macrofy lock prefixes to work around GCC inlining bugs"
Revert "x86/bug: Macrofy the BUG table section handling, to work around GCC inlining bugs"
Revert "x86/paravirt: Work around GCC inlining bugs when compiling paravirt ops"
Revert "x86/extable: Macrofy inline assembly code to work around GCC inlining bugs"
Revert "x86/cpufeature: Macrofy inline assembly code to work around GCC inlining bugs"
Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"
x86/mtrr: Don't copy uninitialized gentry fields back to userspace
x86/fsgsbase/64: Fix the base write helper functions
x86/mm/cpa: Fix cpa_flush_array() TLB invalidation
x86/vdso: Pass --eh-frame-hdr to the linker
x86/mm: Fix decoy address handling vs 32-bit builds
x86/intel_rdt: Ensure a CPU remains online for the region's pseudo-locking sequence
x86/dump_pagetables: Fix LDT remap address marker
x86/mm: Fix guard hole handling
For the same reason as commit 25896d073d ("x86/build: Fix compiler
support check for CONFIG_RETPOLINE"), you cannot put this $(error ...)
into the parse stage of the top Makefile.
Perhaps I'd propose a more sophisticated solution later, but this is
the best I can do for now.
Link: https://lkml.org/lkml/2017/12/25/211
Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Reported-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Reported-by: Qian Cai <cai@lca.pw>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Qian Cai <cai@lca.pw>
This flag is documented in the GCC 4.6 manual, and recognized by
Clang as well. Let's rip off the cc-option switch.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
-Wstrict-prototypes is added to KBUILD_CFLAGS first, then overridden
by -Werror=strict-prototypes later.
Let's add -Werror=strict-prototypes unconditionally because it is
supported by GCC 4.6, and also by Clang.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
This flag is documented in the GCC 4.6 manual, and recognized by
Clang as well. Let's rip off the cc-option switch.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
- Use conventional $(MAKE) $(asm-generic)=<dir> style
for directory descending
- Remove unneeded FORCE since "all" is a phony target
- Remove unneeded "_dummy :=" assignment
- Skip $(shell mkdir ...) when headers exist in the directory
- Misc cleanups
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
This adds the build infrastructure for checking DT binding schema
documents and validating dts files using the binding schema.
Check DT binding schema documents:
make dt_binding_check
Build dts files and check using DT binding schema:
make dtbs_check
Optionally, DT_SCHEMA_FILES can be passed in with a schema file(s) to
use for validation. This makes it easier to find and fix errors
generated by a specific schema.
Currently, the validation targets are separate from a normal build to
avoid a hard dependency on the external DT schema project and because
there are lots of warnings generated.
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: linux-doc@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-kbuild@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
When CONFIG_HEADERS_CHECK is enabled, the headers_check is executed
as a serialized task in the vmlinux recipe.
Make it independent of vmlinux so that parallel building can process
the headers_check and other build targets simultaneously.
Signed-off-by: Masahiro 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 9c2af1c737 ("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 2982c95357 ("kbuild: remove redundant
$(wildcard ...) for cmd_files calculation"), and commit 00d78ab2ba
("kbuild: remove dead code in cmd_files calculation in top Makefile")
because now we must check the presence of targets.
Signed-off-by: Masahiro 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: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Before start descending, Kbuild needs to run 'prepare' and 'scripts',
which has been orthogonal to each other.
Going forward, let's consider 'scripts' is a part of the preparation.
This will allow more cleanups.
Move 'scripts' to the prerequisite of 'archprepare', where UML starts
compiling target *.c files.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
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: Masahiro Yamada <yamada.masahiro@socionext.com>
Building a single target in an external module fails due to missing
.tmp_versions directory.
For example,
$ make -C /lib/modules/$(uname -r)/build M=$PWD foo.o
will fail in the following way:
CC [M] /home/masahiro/foo/foo.o
/bin/sh: 1: cannot create /home/masahiro/foo/.tmp_versions/foo.mod: Directory nonexistent
This is because $(cmd_crmodverdir) is executed only before building
/, %/, %.ko single targets of external modules. Create .tmp_versions
in the 'prepare' target.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
SUBDIRS has been kept as a backward compatibility since
commit ("[PATCH] kbuild: external module support") in 2002.
We do not need multiple ways to do the same thing, so I will remove
SUBDIRS after the Linux 5.3 release. I cleaned up in-tree code, and
updated the document so that nobody would try to use it.
Meanwhile, display the following warning if SUBDIRS is used.
Makefile:189: ================= WARNING ================
Makefile:190: 'SUBDIRS' will be removed after Linux 5.3
Makefile:191: Please use 'M=' or 'KBUILD_EXTMOD' instead
Makefile:192: ==========================================
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Boris Brezillon <boris.brezillon@bootlin.com> # for scx200_docflash.c
Acked-by: Guenter Roeck <linux@roeck-us.net> # for scx200_wdt.c
The powerpc makefile will use these in it's boot wrapper.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Collect basic Clang options such as --target, --prefix, --gcc-toolchain,
-no-integrated-as into a single variable CLANG_FLAGS so that it can be
easily reused in other parts of Makefile.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Greg Hackmann <ghackmann@google.com>
We are still a way off the Clang's integrated assembler support for
the kernel. Hence, -no-integrated-as is mandatory to build the kernel
with Clang. If you had an ancient version of Clang that does not
recognize this option, you would not be able to compile the kernel
anyway.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.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: Masahiro 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: Masahiro 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: Joel Stanley <joel@jms.id.au>
- Remove unused fallback for BUILD_BUG_ON (which technically contains a VLA)
- Lift -Wvla to the top-level Makefile
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Merge tag 'vla-v4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull VLA removal from Kees Cook:
"Globally warn on VLA use.
This turns on "-Wvla" globally now that the last few trees with their
VLA removals have landed (crypto, block, net, and powerpc).
Arnd mentioned that there may be a couple more VLAs hiding in
hard-to-find randconfigs, but nothing big has shaken out in the last
month or so in linux-next.
We should be basically VLA-free now! Wheee. :)
Summary:
- Remove unused fallback for BUILD_BUG_ON (which technically contains
a VLA)
- Lift -Wvla to the top-level Makefile"
* tag 'vla-v4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
Makefile: Globally enable VLA warning
compiler.h: give up __compiletime_assert_fallback()
- optimize kallsyms slightly
- remove check for old CFLAGS usage
- add some compiler flags unconditionally instead of evaluating
$(call cc-option,...)
- fix variable shadowing in host tools
- refactor scripts/mkmakefile
- refactor various makefiles
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Merge tag 'kbuild-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- optimize kallsyms slightly
- remove check for old CFLAGS usage
- add some compiler flags unconditionally instead of evaluating
$(call cc-option,...)
- fix variable shadowing in host tools
- refactor scripts/mkmakefile
- refactor various makefiles
* tag 'kbuild-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
modpost: Create macro to avoid variable shadowing
ASN.1: Remove unnecessary shadowed local variable
kbuild: use 'else ifeq' for checksrc to improve readability
kbuild: remove unneeded link_multi_deps
kbuild: add -Wno-unused-but-set-variable flag unconditionally
kbuild: add -Wdeclaration-after-statement flag unconditionally
kbuild: add -Wno-pointer-sign flag unconditionally
modpost: remove leftover symbol prefix handling for module device table
kbuild: simplify command line creation in scripts/mkmakefile
kbuild: do not pass $(objtree) to scripts/mkmakefile
kbuild: remove user ID check in scripts/mkmakefile
kbuild: remove VERSION and PATCHLEVEL from $(objtree)/Makefile
kbuild: add --include-dir flag only for out-of-tree build
kbuild: remove dead code in cmd_files calculation in top Makefile
kbuild: hide most of targets when running config or mixed targets
kbuild: remove old check for CFLAGS use
kbuild: prefix Makefile.dtbinst path with $(srctree) unconditionally
kallsyms: remove left-over Blackfin code
kallsyms: reduce size a little on 64-bit
- Sync dtc with upstream version v1.4.7-14-gc86da84d30e4
- Work to get rid of direct accesses to struct device_node name and
type pointers in preparation for removing them. New helpers for
parsing DT cpu nodes and conversions to use the helpers. printk
conversions to %pOFn for printing DT node names. Most went thru
subystem trees, so this is the remainder.
- Fixes to DT child node lookups to actually be restricted to child
nodes instead of treewide.
- Refactoring of dtb targets out of arch code. This makes the support
more uniform and enables building all dtbs on c6x, microblaze, and
powerpc.
- Various DT binding updates for Renesas r8a7744 SoC
- Vendor prefixes for Facebook, OLPC
- Restructuring of some ARM binding docs moving some peripheral bindings
out of board/SoC binding files
- New "secure-chosen" binding for secure world settings on ARM
- Dual licensing of 2 DT IRQ binding headers
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Merge tag 'devicetree-for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull Devicetree updates from Rob Herring:
"A bit bigger than normal as I've been busy this cycle.
There's a few things with dependencies and a few things subsystem
maintainers didn't pick up, so I'm taking them thru my tree.
The fixes from Johan didn't get into linux-next, but they've been
waiting for some time now and they are what's left of what subsystem
maintainers didn't pick up.
Summary:
- Sync dtc with upstream version v1.4.7-14-gc86da84d30e4
- Work to get rid of direct accesses to struct device_node name and
type pointers in preparation for removing them. New helpers for
parsing DT cpu nodes and conversions to use the helpers. printk
conversions to %pOFn for printing DT node names. Most went thru
subystem trees, so this is the remainder.
- Fixes to DT child node lookups to actually be restricted to child
nodes instead of treewide.
- Refactoring of dtb targets out of arch code. This makes the support
more uniform and enables building all dtbs on c6x, microblaze, and
powerpc.
- Various DT binding updates for Renesas r8a7744 SoC
- Vendor prefixes for Facebook, OLPC
- Restructuring of some ARM binding docs moving some peripheral
bindings out of board/SoC binding files
- New "secure-chosen" binding for secure world settings on ARM
- Dual licensing of 2 DT IRQ binding headers"
* tag 'devicetree-for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (78 commits)
ARM: dt: relicense two DT binding IRQ headers
power: supply: twl4030-charger: fix OF sibling-node lookup
NFC: nfcmrvl_uart: fix OF child-node lookup
net: stmmac: dwmac-sun8i: fix OF child-node lookup
net: bcmgenet: fix OF child-node lookup
drm/msm: fix OF child-node lookup
drm/mediatek: fix OF sibling-node lookup
of: Add missing exports of node name compare functions
dt-bindings: Add OLPC vendor prefix
dt-bindings: misc: bk4: Add device tree binding for Liebherr's BK4 SPI bus
dt-bindings: thermal: samsung: Add SPDX license identifier
dt-bindings: clock: samsung: Add SPDX license identifiers
dt-bindings: timer: ostm: Add R7S9210 support
dt-bindings: phy: rcar-gen2: Add r8a7744 support
dt-bindings: can: rcar_can: Add r8a7744 support
dt-bindings: timer: renesas, cmt: Document r8a7744 CMT support
dt-bindings: watchdog: renesas-wdt: Document r8a7744 support
dt-bindings: thermal: rcar: Add device tree support for r8a7744
Documentation: dt: Add binding for /secure-chosen/stdout-path
dt-bindings: arm: zte: Move sysctrl bindings to their own doc
...
Pull locking and misc x86 updates from Ingo Molnar:
"Lots of changes in this cycle - in part because locking/core attracted
a number of related x86 low level work which was easier to handle in a
single tree:
- Linux Kernel Memory Consistency Model updates (Alan Stern, Paul E.
McKenney, Andrea Parri)
- lockdep scalability improvements and micro-optimizations (Waiman
Long)
- rwsem improvements (Waiman Long)
- spinlock micro-optimization (Matthew Wilcox)
- qspinlocks: Provide a liveness guarantee (more fairness) on x86.
(Peter Zijlstra)
- Add support for relative references in jump tables on arm64, x86
and s390 to optimize jump labels (Ard Biesheuvel, Heiko Carstens)
- Be a lot less permissive on weird (kernel address) uaccess faults
on x86: BUG() when uaccess helpers fault on kernel addresses (Jann
Horn)
- macrofy x86 asm statements to un-confuse the GCC inliner. (Nadav
Amit)
- ... and a handful of other smaller changes as well"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits)
locking/lockdep: Make global debug_locks* variables read-mostly
locking/lockdep: Fix debug_locks off performance problem
locking/pvqspinlock: Extend node size when pvqspinlock is configured
locking/qspinlock_stat: Count instances of nested lock slowpaths
locking/qspinlock, x86: Provide liveness guarantee
x86/asm: 'Simplify' GEN_*_RMWcc() macros
locking/qspinlock: Rework some comments
locking/qspinlock: Re-order code
locking/lockdep: Remove duplicated 'lock_class_ops' percpu array
x86/defconfig: Enable CONFIG_USB_XHCI_HCD=y
futex: Replace spin_is_locked() with lockdep
locking/lockdep: Make class->ops a percpu counter and move it under CONFIG_DEBUG_LOCKDEP=y
x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs
x86/cpufeature: Macrofy inline assembly code to work around GCC inlining bugs
x86/extable: Macrofy inline assembly code to work around GCC inlining bugs
x86/paravirt: Work around GCC inlining bugs when compiling paravirt ops
x86/bug: Macrofy the BUG table section handling, to work around GCC inlining bugs
x86/alternatives: Macrofy lock prefixes to work around GCC inlining bugs
x86/refcount: Work around GCC inlining bug
x86/objtool: Use asm macros to work around GCC inlining bugs
...
We have raised the compiler requirement from time to time.
With commit cafa0010cd ("Raise the minimum required gcc version
to 4.6"), the minimum for GCC is 4.6 now.
This flag was added by GCC 4.6, and it is recognized by ICC as well.
It is true that Clang does not support this flag but this commit is
just touching the else part of the "ifeq ($(cc-name),clang)" check.
Hence, Clang build is not affected.
Let's rip off the cc-disable-warning switch, and see if somebody
complains about it.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
We have raised the compiler requirement from time to time.
With commit cafa0010cd ("Raise the minimum required gcc version
to 4.6"), the minimum for GCC is 4.6 now.
This flag has been here since the pre-git era. It is documented in
the GCC 4.6 manual, and it is recognized by Clang and ICC as well.
Let's rip off the cc-option switch, and see if somebody complains
about it.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
We have raised the compiler requirement from time to time.
With commit cafa0010cd ("Raise the minimum required gcc version
to 4.6"), the minimum for GCC is 4.6 now.
The -Wno-pointer-sign has been here since the pre-git era. It is
documented in the GCC 4.6 manual, and it is recognized by Clang
and ICC as well.
Let's rip off the cc-disable-warning switch, and see if somebody
complains about it.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
- Fix warnings from recordmcount.pl when building with Clang
- Allow Clang to use GNU toolchains correctly
- Disable CONFIG_SAMPLES for UML to avoid build error
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Merge tag 'kbuild-fixes-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Masahiro writes:
"Kbuild fixes for v4.19 (2nd)
- Fix warnings from recordmcount.pl when building with Clang
- Allow Clang to use GNU toolchains correctly
- Disable CONFIG_SAMPLES for UML to avoid build error"
* tag 'kbuild-fixes-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
samples: disable CONFIG_SAMPLES for UML
kbuild: allow to use GCC toolchain not in Clang search path
ftrace: Build with CPPFLAGS to get -Qunused-arguments
Since $(objtree) is always '.', it is not useful to pass it to
scripts/mkmakefile. I assume nobody wants to run this script directly.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The --include-dir flag is used to include check-in Makefiles from
$(objtree) without $(srctree)/ prefix. Obviously, this is unneeded
for in-tree build. Add the flag just before changing the working
directory.
This becomes effective after invoking sub-make. Add a little bit
comments about it.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Using macros in inline assembly allows us to work around bugs
in GCC's inlining decisions.
Compile macros.S and use it to assemble all C files.
Currently only x86 will use it.
Background:
The inlining pass of GCC doesn't include an assembler, so it's not aware
of basic properties of the generated code, such as its size in bytes,
or that there are such things as discontiuous blocks of code and data
due to the newfangled linker feature called 'sections' ...
Instead GCC uses a lazy and fragile heuristic: it does a linear count of
certain syntactic and whitespace elements in inlined assembly block source
code, such as a count of new-lines and semicolons (!), as a poor substitute
for "code size and complexity".
Unsurprisingly this heuristic falls over and breaks its neck whith certain
common types of kernel code that use inline assembly, such as the frequent
practice of putting useful information into alternative sections.
As a result of this fresh, 20+ years old GCC bug, GCC's inlining decisions
are effectively disabled for inlined functions that make use of such asm()
blocks, because GCC thinks those sections of code are "large" - when in
reality they are often result in just a very low number of machine
instructions.
This absolute lack of inlining provess when GCC comes across such asm()
blocks both increases generated kernel code size and causes performance
overhead, which is particularly noticeable on paravirt kernels, which make
frequent use of these inlining facilities in attempt to stay out of the
way when running on baremetal hardware.
Instead of fixing the compiler we use a workaround: we set an assembly macro
and call it from the inlined assembly block. As a result GCC considers the
inline assembly block as a single instruction. (Which it often isn't but I digress.)
This uglifies and bloats the source code - for example just the refcount
related changes have this impact:
Makefile | 9 +++++++--
arch/x86/Makefile | 7 +++++++
arch/x86/kernel/macros.S | 7 +++++++
scripts/Kbuild.include | 4 +++-
scripts/mod/Makefile | 2 ++
5 files changed, 26 insertions(+), 3 deletions(-)
Yay readability and maintainability, it's not like assembly code is hard to read
and maintain ...
We also hope that GCC will eventually get fixed, but we are not holding
our breath for that. Yet we are optimistic, it might still happen, any decade now.
[ mingo: Wrote new changelog describing the background. ]
Tested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Nadav Amit <namit@vmware.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kbuild@vger.kernel.org
Link: http://lkml.kernel.org/r/20181003213100.189959-3-namit@vmware.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There is nothing arch specific about building dtb files other than their
location under /arch/*/boot/dts/. Keeping each arch aligned is a pain.
The dependencies and supported targets are all slightly different.
Also, a cross-compiler for each arch is needed, but really the host
compiler preprocessor is perfectly fine for building dtbs. Move the
build rules to a common location and remove the arch specific ones. This
is done in a single step to avoid warnings about overriding rules.
The build dependencies had been a mixture of 'scripts' and/or 'prepare'.
These pull in several dependencies some of which need a target compiler
(specifically devicetable-offsets.h) and aren't needed to build dtbs.
All that is really needed is dtc, so adjust the dependencies to only be
dtc.
This change enables support 'dtbs_install' on some arches which were
missing the target.
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Paul Burton <paul.burton@mips.com>
Acked-by: Ley Foon Tan <ley.foon.tan@intel.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-kbuild@vger.kernel.org
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: uclinux-h8-devel@lists.sourceforge.jp
Cc: linux-mips@linux-mips.org
Cc: nios2-dev@lists.rocketboards.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-xtensa@linux-xtensa.org
Signed-off-by: Rob Herring <robh@kernel.org>
When using a GCC cross toolchain which is not in a compiled in
Clang search path, Clang reverts to the system assembler and
linker. This leads to assembler or linker errors, depending on
which tool is first used for a given architecture.
It seems that Clang is not searching $PATH for a matching
assembler or linker.
Make sure that Clang picks up the correct assembler or linker by
passing the cross compilers bin directory as search path.
This allows to use Clang provided by distributions with GCC
toolchains not in /usr/bin.
Link: https://github.com/ClangBuiltLinux/linux/issues/78
Signed-off-by: Stefan Agner <stefan@agner.ch>
Reviewed-and-tested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
This Kselftest fixes update for 4.9-rc5 consists of:
-- fixes to build failures
-- fixes to add missing config files to increase test coverage
-- fixes to cgroup test and a new cgroup test for memory.oom.group
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Merge tag 'linux-kselftest-4.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pulled kselftest fixes from Shuah:
"This Kselftest fixes update for 4.9-rc5 consists of:
-- fixes to build failures
-- fixes to add missing config files to increase test coverage
-- fixes to cgroup test and a new cgroup test for memory.oom.group"
Nobody sets 'targets' in the top-level Makefile or arch/*/Makefile,
hence $(targets) is empty.
$(wildcard .*.cmd) will do for including the .vmlinux.cmd file.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
When mixed/config targets are being processed, the top Makefile
does not need to parse the rest of targets.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
As a Kernel developer, I make heavy use of "make targz-pkg" in order
to locally compile and remotely install my development Kernels. The
nice feature I rely on is that after a normal "make", "make targz-pkg"
only generates the tarball without having to recompile everything.
That was true until commit f28bc3c32c ("tracing: Handle
CC_FLAGS_FTRACE more accurately"). After it, running "make targz-pkg"
after "make" will recompile the whole Kernel tree, making my
development workflow much slower.
The Kernel is choosing to recompile everything because it claims the
command line has changed. A diff of the .cmd files show a repeated
-mfentry in one of the files. That is because "make targz-pkg" calls
"make modules_install" and the environment is already populated with
the exported variables, CC_FLAGS_FTRACE being one of them. Then,
-mfentry gets duplicated because it is not protected behind an ifndef
block, like -pg.
To complicate the problem a little bit more, architectures can define
their own version CC_FLAGS_FTRACE, so our code not only has to
consider recursive Makefiles, but also architecture overrides.
So in this patch we move CC_FLAGS_FTRACE up and unconditionally
define it to -pg. Then we let the architecture Makefiles possibly
override it, and finally append the extra options later. This ensures
the variable is always fully redefined at each invocation so recursive
Makefiles don't keep appending, and hopefully it maintains the
intended behavior on how architectures can override the defaults..
Thanks Steven Rostedt and Vasily Gorbik for the help on this
regression.
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: linux-kbuild@vger.kernel.org
Fixes: commit f28bc3c32c ("tracing: Handle CC_FLAGS_FTRACE more accurately")
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If the kernel headers aren't installed we can't build all the tests.
Add a new make target rule 'khdr' in the file lib.mk to generate the
kernel headers and that gets include for every test-dir Makefile that
includes lib.mk If the testdir in turn have its own sub-dirs the
top_srcdir needs to be set to the linux-rootdir to be able to generate
the kernel headers.
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Reviewed-by: Fathi Boudra <fathi.boudra@linaro.org>
Signed-off-by: Shuah Khan (Samsung OSG) <shuah@kernel.org>
Pull x86 fixes from Thomas Gleixner:
- Correct the L1TF fallout on 32bit and the off by one in the 'too much
RAM for protection' calculation.
- Add a helpful kernel message for the 'too much RAM' case
- Unbreak the VDSO in case that the compiler desides to use indirect
jumps/calls and emits retpolines which cannot be resolved because the
kernel uses its own thunks, which does not work for the VDSO. Make it
use the builtin thunks.
- Re-export start_thread() which was unexported when the 32/64bit
implementation was unified. start_thread() is required by modular
binfmt handlers.
- Trivial cleanups
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/speculation/l1tf: Suggest what to do on systems with too much RAM
x86/speculation/l1tf: Fix off-by-one error when warning that system has too much RAM
x86/kvm/vmx: Remove duplicate l1d flush definitions
x86/speculation/l1tf: Fix overflow in l1tf_pfn_limit() on 32bit
x86/process: Re-export start_thread()
x86/mce: Add notifier_block forward declaration
x86/vdso: Fix vDSO build if a retpoline is emitted
Commit a0f97e06a4 ("kbuild: enable 'make CFLAGS=...' to add
additional options to CC") renamed CFLAGS to KBUILD_CFLAGS.
Commit 222d394d30 ("kbuild: enable 'make AFLAGS=...' to add
additional options to AS") renamed AFLAGS to KBUILD_AFLAGS.
Commit 06c5040cdb ("kbuild: enable 'make CPPFLAGS=...' to add
additional options to CPP") renamed CPPFLAGS to KBUILD_CPPFLAGS.
For some reason, LDFLAGS was not renamed.
Using a well-known variable like LDFLAGS may result in accidental
override of the variable.
Kbuild generally uses KBUILD_ prefixed variables for the internally
appended options, so here is one more conversion to sanitize the
naming convention.
I did not touch Makefiles under tools/ since the tools build system
is a different world.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
This config option should be enabled only when both the compiler and
the linker support necessary flags. Add proper dependencies to Kconfig.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
As commit ebaad7d364 ("kbuild: rpm: prompt to use "rpm-pkg" if "rpm"
target is used") noticed, the "rpm" target is now removed.
I assume people have already migrated to "rpm-pkg".
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
- Restructure of lockdep and latency tracers
This is the biggest change. Joel Fernandes restructured the hooks
from irqs and preemption disabling and enabling. He got rid of
a lot of the preprocessor #ifdef mess that they caused.
He turned both lockdep and the latency tracers to use trace events
inserted in the preempt/irqs disabling paths. But unfortunately,
these started to cause issues in corner cases. Thus, parts of the
code was reverted back to where lockde and the latency tracers
just get called directly (without using the trace events).
But because the original change cleaned up the code very nicely
we kept that, as well as the trace events for preempt and irqs
disabling, but they are limited to not being called in NMIs.
- Have trace events use SRCU for "rcu idle" calls. This was required
for the preempt/irqs off trace events. But it also had to not
allow them to be called in NMI context. Waiting till Paul makes
an NMI safe SRCU API.
- New notrace SRCU API to allow trace events to use SRCU.
- Addition of mcount-nop option support
- SPDX headers replacing GPL templates.
- Various other fixes and clean ups.
- Some fixes are marked for stable, but were not fully tested
before the merge window opened.
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Merge tag 'trace-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
- Restructure of lockdep and latency tracers
This is the biggest change. Joel Fernandes restructured the hooks
from irqs and preemption disabling and enabling. He got rid of a lot
of the preprocessor #ifdef mess that they caused.
He turned both lockdep and the latency tracers to use trace events
inserted in the preempt/irqs disabling paths. But unfortunately,
these started to cause issues in corner cases. Thus, parts of the
code was reverted back to where lockdep and the latency tracers just
get called directly (without using the trace events). But because the
original change cleaned up the code very nicely we kept that, as well
as the trace events for preempt and irqs disabling, but they are
limited to not being called in NMIs.
- Have trace events use SRCU for "rcu idle" calls. This was required
for the preempt/irqs off trace events. But it also had to not allow
them to be called in NMI context. Waiting till Paul makes an NMI safe
SRCU API.
- New notrace SRCU API to allow trace events to use SRCU.
- Addition of mcount-nop option support
- SPDX headers replacing GPL templates.
- Various other fixes and clean ups.
- Some fixes are marked for stable, but were not fully tested before
the merge window opened.
* tag 'trace-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (44 commits)
tracing: Fix SPDX format headers to use C++ style comments
tracing: Add SPDX License format tags to tracing files
tracing: Add SPDX License format to bpf_trace.c
blktrace: Add SPDX License format header
s390/ftrace: Add -mfentry and -mnop-mcount support
tracing: Add -mcount-nop option support
tracing: Avoid calling cc-option -mrecord-mcount for every Makefile
tracing: Handle CC_FLAGS_FTRACE more accurately
Uprobe: Additional argument arch_uprobe to uprobe_write_opcode()
Uprobes: Simplify uprobe_register() body
tracepoints: Free early tracepoints after RCU is initialized
uprobes: Use synchronize_rcu() not synchronize_sched()
tracing: Fix synchronizing to event changes with tracepoint_synchronize_unregister()
ftrace: Remove unused pointer ftrace_swapper_pid
tracing: More reverting of "tracing: Centralize preemptirq tracepoints and unify their usage"
tracing/irqsoff: Handle preempt_count for different configs
tracing: Partial revert of "tracing: Centralize preemptirq tracepoints and unify their usage"
tracing: irqsoff: Account for additional preempt_disable
trace: Use rcu_dereference_raw for hooks from trace-event subsystem
tracing/kprobes: Fix within_notrace_func() to check only notrace functions
...
Currently, if the vDSO ends up containing an indirect branch or
call, GCC will emit the "external thunk" style of retpoline, and it
will fail to link.
Fix it by building the vDSO with inline retpoline thunks.
I haven't seen any reports of this triggering on an unpatched
kernel.
Fixes: commit 76b043848f ("x86/retpoline: Add initial retpoline support")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Matt Rickard <matt@softrans.com.au>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jason Vas Dias <jason.vas.dias@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/c76538cd3afbe19c6246c2d1715bc6a60bd63985.1534448381.git.luto@kernel.org
-mcount-nop gcc option generates the calls to the profiling functions
as nops which allows to avoid patching mcount jump with NOP instructions
initially.
-mcount-nop gcc option will be activated if platform selects
HAVE_NOP_MCOUNT and gcc actually supports it.
In addition to that CC_USING_NOP_MCOUNT is defined and could be used by
architectures to adapt ftrace patching behavior.
Link: http://lkml.kernel.org/r/patch-3.thread-aa7b8d.git-e02ed2dc082b.your-ad-here.call-01533557518-ext-9465@work.hours
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
