Allow additional arguments be passed to userprogs compilation.
Reproducible clang builds need to provide a sysroot and gcc path to
ensure the same toolchain is used across hosts. KCFLAGS is not currently
used for any user programs compilation, so add new USERCFLAGS and
USERLDFLAGS which serves similar purpose as HOSTCFLAGS/HOSTLDFLAGS.
Clang might detect GCC installation on hosts which have it installed
to a default location in /. With addition of these environment
variables, you can specify flags such as:
$ make USERCFLAGS=--sysroot=/path/to/sysroot
This can also be used to specify different sysroots such as musl or
bionic which may be installed on the host in paths that the compiler
may not search by default.
Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Fangrui Song <maskray@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Documentation/kbuild/makefiles.rst suggests to use "archclean" for
cleaning arch/$(SRCARCH)/boot/, but it is not a hard requirement.
Since commit d92cc4d516 ("kbuild: require all architectures to have
arch/$(SRCARCH)/Kbuild"), we can use the "subdir- += boot" trick for
all architectures. This can take advantage of the parallel option (-j)
for "make clean".
I also cleaned up the comments in arch/$(SRCARCH)/Makefile. The "archdep"
target no longer exists.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
- Fix false-positive build warnings for ARCH=ia64 builds
- Optimize dictionary size for module compression with xz
- Check the compiler and linker versions in Kconfig
- Fix misuse of extra-y
- Support DWARF v5 debug info
- Clamp SUBLEVEL to 255 because stable releases 4.4.x and 4.9.x
exceeded the limit
- Add generic syscall{tbl,hdr}.sh for cleanups across arches
- Minor cleanups of genksyms
- Minor cleanups of Kconfig
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Merge tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- Fix false-positive build warnings for ARCH=ia64 builds
- Optimize dictionary size for module compression with xz
- Check the compiler and linker versions in Kconfig
- Fix misuse of extra-y
- Support DWARF v5 debug info
- Clamp SUBLEVEL to 255 because stable releases 4.4.x and 4.9.x
exceeded the limit
- Add generic syscall{tbl,hdr}.sh for cleanups across arches
- Minor cleanups of genksyms
- Minor cleanups of Kconfig
* tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (38 commits)
initramfs: Remove redundant dependency of RD_ZSTD on BLK_DEV_INITRD
kbuild: remove deprecated 'always' and 'hostprogs-y/m'
kbuild: parse C= and M= before changing the working directory
kbuild: reuse this-makefile to define abs_srctree
kconfig: unify rule of config, menuconfig, nconfig, gconfig, xconfig
kconfig: omit --oldaskconfig option for 'make config'
kconfig: fix 'invalid option' for help option
kconfig: remove dead code in conf_askvalue()
kconfig: clean up nested if-conditionals in check_conf()
kconfig: Remove duplicate call to sym_get_string_value()
Makefile: Remove # characters from compiler string
Makefile: reuse CC_VERSION_TEXT
kbuild: check the minimum linker version in Kconfig
kbuild: remove ld-version macro
scripts: add generic syscallhdr.sh
scripts: add generic syscalltbl.sh
arch: syscalls: remove $(srctree)/ prefix from syscall tables
arch: syscalls: add missing FORCE and fix 'targets' to make if_changed work
gen_compile_commands: prune some directories
kbuild: simplify access to the kernel's version
...
This series consists of the usual driver updates (ufs, ibmvfc,
qla2xxx, hisi_sas, pm80xx) plus the removal of the gdth driver (which
is bound to cause conflicts with a trivial change somewhere). The
only big major rework of note is the one from Hannes trying to clean
up our result handling code in the drivers to make it consistent.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"This series consists of the usual driver updates (ufs, ibmvfc,
qla2xxx, hisi_sas, pm80xx) plus the removal of the gdth driver (which
is bound to cause conflicts with a trivial change somewhere).
The only big major rework of note is the one from Hannes trying to
clean up our result handling code in the drivers to make it
consistent"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (194 commits)
scsi: MAINTAINERS: Adjust to reflect gdth scsi driver removal
scsi: ufs: Give clk scaling min gear a value
scsi: lpfc: Fix 'physical' typos
scsi: megaraid_mbox: Fix spelling of 'allocated'
scsi: qla2xxx: Simplify the calculation of variables
scsi: message: fusion: Fix 'physical' typos
scsi: target: core: Change ASCQ for residual write
scsi: target: core: Signal WRITE residuals
scsi: target: core: Set residuals for 4Kn devices
scsi: hisi_sas: Add trace FIFO debugfs support
scsi: hisi_sas: Flush workqueue in hisi_sas_v3_remove()
scsi: hisi_sas: Enable debugfs support by default
scsi: hisi_sas: Don't check .nr_hw_queues in hisi_sas_task_prep()
scsi: hisi_sas: Remove deferred probe check in hisi_sas_v2_probe()
scsi: lpfc: Add auto select on IRQ_POLL
scsi: ncr53c8xx: Fix typos
scsi: lpfc: Fix ancient double free
scsi: qla2xxx: Fix some memory corruption
scsi: qla2xxx: Remove redundant NULL check
scsi: megaraid: Fix ifnullfree.cocci warnings
...
The "oprofile" user-space tools don't use the kernel OPROFILE support any more,
and haven't in a long time. User-space has been converted to the perf
interfaces.
The dcookies stuff is only used by the oprofile code. Now that oprofile's
support is getting removed from the kernel, there is no need for dcookies as
well.
Remove kernel's old oprofile and dcookies support.
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Merge tag 'oprofile-removal-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/linux
Pull oprofile and dcookies removal from Viresh Kumar:
"Remove oprofile and dcookies support
The 'oprofile' user-space tools don't use the kernel OPROFILE support
any more, and haven't in a long time. User-space has been converted to
the perf interfaces.
The dcookies stuff is only used by the oprofile code. Now that
oprofile's support is getting removed from the kernel, there is no
need for dcookies as well.
Remove kernel's old oprofile and dcookies support"
* tag 'oprofile-removal-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/linux:
fs: Remove dcookies support
drivers: Remove CONFIG_OPROFILE support
arch: xtensa: Remove CONFIG_OPROFILE support
arch: x86: Remove CONFIG_OPROFILE support
arch: sparc: Remove CONFIG_OPROFILE support
arch: sh: Remove CONFIG_OPROFILE support
arch: s390: Remove CONFIG_OPROFILE support
arch: powerpc: Remove oprofile
arch: powerpc: Stop building and using oprofile
arch: parisc: Remove CONFIG_OPROFILE support
arch: mips: Remove CONFIG_OPROFILE support
arch: microblaze: Remove CONFIG_OPROFILE support
arch: ia64: Remove rest of perfmon support
arch: ia64: Remove CONFIG_OPROFILE support
arch: hexagon: Don't select HAVE_OPROFILE
arch: arc: Remove CONFIG_OPROFILE support
arch: arm: Remove CONFIG_OPROFILE support
arch: alpha: Remove CONFIG_OPROFILE support
Python retired in 2020, and some distributions do not provide the
'python' command any more.
As in commit 51839e29cb ("scripts: switch explicitly to Python 3"),
we need to use more specific 'python3' to invoke scripts even if they
are written in a way compatible with both Python 2 and 3.
This commit removes the variable 'PYTHON', and switches the existing
users to 'PYTHON3'.
BTW, PEP 394 (https://www.python.org/dev/peps/pep-0394/) is a helpful
material.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The "oprofile" user-space tools don't use the kernel OPROFILE support
any more, and haven't in a long time. User-space has been converted to
the perf interfaces.
Remove the old oprofile's architecture specific support.
Suggested-by: Christoph Hellwig <hch@infradead.org>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Robert Richter <rric@kernel.org>
Acked-by: William Cohen <wcohen@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
The gdth driver refers to a SCSI parallel, PCI-only HBA RAID adapter which
was manufactured by the now-defunct ICP Vortex company, later acquired by
Adaptec and superseded by the aacraid series of controllers. The driver
itself would require a major overhaul before any modifications can be
attempted, but seeing that it's unlikely to have any users left it should
rather be removed completely.
Link: https://lore.kernel.org/r/20210113090500.129644-2-hare@suse.de
Cautiously-Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
There is no explanation about subdir-y.
Let's document it.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
The difference between extra-y and always-y is obscure.
Basically, Kbuild builds targets listed in extra-y and always-y in
visited Makefiles without relying on any dependency.
The difference is that extra-y is used to list the targets needed for
vmlinux whereas always-y is used to list the targets that must be always
built irrespective of final targets.
Kbuild skips extra-y when it is building only modules (i.e.
'make modules'). This is the long-standing behavior since extra-y was
introduced in 2003, and it is explained in that commit log [1].
For clarification, this is the extra-y vs always-y table:
extra-y always-y
'make' y y
'make vmlinux' y y
'make modules' n y
Kbuild skips extra-y also when building external modules since obviously
it never builds vmlinux.
Unfortunately, extra-y is wrongly used in many places of upstream code,
and even in external modules.
Using extra-y in external module Makefiles is wrong. What you should
use is probably always-y or 'targets'.
The current documentation for extra-y is misleading. I rewrote it, and
moved it to the section 3.7.
always-y is not documented anywhere. I added.
[1]: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=f94e5fd7e5d09a56a60670a9bb211a791654bba8
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
The if_changed macro is currently explained in the section
"Commands useful for building a boot image", but the use of
if_changed is not limited to the boot image.
It is often used together with custom rules. Let's split it as a
separate section, and insert it after the "Custom Rules" section.
I slightly reworded the explanation, re-numbered to fill the <deleted>
section, and also fixed the broken indentation of the Note: part.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The two sections "3.10 Special Rules" and "7.8 Custom kbuild commands"
are related because you must understand both of them when you write
custom rules.
Actually I do not understand the policy about what to go into
"3 The kbuild files" and what into "7 Architecture Makefile".
This commit reworks the custom rule explanation as follows:
- Merged "7.8 Custom kbuild commands" into "3.10 Special Rules".
- Reword "Special Rules" to "Custom Rules" for consistency.
- Update the example for kecho because the blackfin Makefile
does not exist any more.
- Replace the example for cmd_<command> with a simpler one.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Fix stale information:
- Fix the section number in the reference from 6.4 to 7.4.
- Remove init-y and net-y. They were removed by commit 23febe375d
("kbuild: merge init-y into core-y") and commit 95fb6317b3
("kbuild: merge net-y and virt-y into drivers-y"), respectively.
- Update the example because arch/sparc64/Makefile does not exit.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Precisely speaking, the arch directory is specified by $(SRCARCH),
not $(ARCH).
In old days, $(ARCH) actually matched to the arch directory because
32-bit and 64-bit were supported as separate architectures.
Most architectures (except arm/arm64) were unified like follows:
arch/i386, arch/x86_64 -> arch/x86
arch/sh, arch/sh64 -> arch/sh
arch/sparc, arch/sparc64 -> arch/sparc
To not break the user interface, commit 6752ed90da ("Kbuild: allow
arch/xxx to use a different source path") introduced SRCARCH to point
to the arch directory, still allowing to pass in the former ARCH=i386
or ARCH=x86_64.
Update the documents for preciseness, and add the explanation of SRCARCH.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
This line was written in 2003. Now we have much more Makefiles.
The number of Makefiles is not important. The point is we have a
Makefile in (almost) every directory.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
During an investigation to fix up the execute bits of scripts in the
kernel repository, Andrew Morton and Kees Cook pointed out that the
execute bit should not matter, and that build scripts cannot rely on that.
Kees could not point to any documentation, though.
Masahiro Yamada explained the convention of setting execute bits to make
it easier for manual script invocation.
Provide some basic documentation how the build shall invoke scripts, such
that the execute bits do not matter, and acknowledge that execute bits are
useful nonetheless.
This serves as reference for further clean-up patches in the future.
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ujjwal Kumar <ujjwalkumar0501@gmail.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Link: https://lore.kernel.org/lkml/20200830174409.c24c3f67addcce0cea9a9d4c@linux-foundation.org/
Link: https://lore.kernel.org/lkml/202008271102.FEB906C88@keescook/
Link: https://lore.kernel.org/linux-kbuild/CAK7LNAQdrvMkDA6ApDJCGr+5db8SiPo=G+p8EiOvnnGvEN80gA@mail.gmail.com/
Link: https://lkml.kernel.org/r/20201001075723.24246-1-lukas.bulwahn@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is a general cleanup of kbuild/makefiles.rst:
* Use "Chapter" for major heading references and use "section" for
the next-level heading references, for consistency.
* Section 3.8 was deleted long ago.
* Drop the ending ':' in section names in the contents list.
* Correct some section numbering references.
* Correct verb agreement typo.
* Fix run-on sentence punctuation.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
To build host programs, you need to add the program names to 'hostprogs'
to use the necessary build rule, but it is not enough to build them
because there is no dependency.
There are two types of host programs: built as the prerequisite of
another (e.g. gen_crc32table in lib/Makefile), or always built when
Kbuild visits the Makefile (e.g. genksyms in scripts/genksyms/Makefile).
The latter is typical in Makefiles under scripts/, which contains host
programs globally used during the kernel build. To build them, you need
to add them to both 'hostprogs' and 'always-y'.
This commit adds hostprogs-always-y as a shorthand.
The same applies to user programs. net/bpfilter/Makefile builds
bpfilter_umh on demand, hence always-y is unneeded. In contrast,
programs under samples/ are added to both 'userprogs' and 'always-y'
so they are always built when Kbuild visits the Makefiles.
userprogs-always-y works as a shorthand.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
CFLAGS_REMOVE_<file>.o filters out flags when compiling a particular
object, but there is no convenient way to do that for every object in
a directory.
Add ccflags-remove-y and asflags-remove-y to make it easily.
Use ccflags-remove-y to clean up some Makefiles.
The add/remove order works as follows:
[1] KBUILD_CFLAGS specifies compiler flags used globally
[2] ccflags-y adds compiler flags for all objects in the
current Makefile
[3] ccflags-remove-y removes compiler flags for all objects in the
current Makefile (New feature)
[4] CFLAGS_<file> adds compiler flags per file.
[5] CFLAGS_REMOVE_<file> removes compiler flags per file.
Having [3] before [4] allows us to remove flags from most (but not all)
objects in the current Makefile.
For example, kernel/trace/Makefile removes $(CC_FLAGS_FTRACE)
from all objects in the directory, then adds it back to
trace_selftest_dynamic.o and CFLAGS_trace_kprobe_selftest.o
The same applies to lib/livepatch/Makefile.
Please note ccflags-remove-y has no effect to the sub-directories.
In contrast, the previous notation got rid of compiler flags also from
all the sub-directories.
The following are not affected because they have no sub-directories:
arch/arm/boot/compressed/
arch/powerpc/xmon/
arch/sh/
kernel/trace/
However, lib/ has several sub-directories.
To keep the behavior, I added ccflags-remove-y to all Makefiles
in subdirectories of lib/, except the following:
lib/vdso/Makefile - Kbuild does not descend into this Makefile
lib/raid/test/Makefile - This is not used for the kernel build
I think commit 2464a609de ("ftrace: do not trace library functions")
excluded too much. In the next commit, I will remove ccflags-remove-y
from the sub-directories of lib/.
Suggested-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Brendan Higgins <brendanhiggins@google.com> (KUnit)
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Kbuild now supports the syntax 'userprogs' to compile userspace
programs for the same architecture as the kernel.
Insert the section '5 Userspace Program support' to explain it.
I copy-pasted '4 Host Program support' and fixed it up.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
This sentence does not make sense in the section about mandatory-y.
This seems to be a copy-paste mistake of commit fcc8487d47 ("uapi:
export all headers under uapi directories").
The correct description would be "The convention is to list one
mandatory-y per line ...".
I just removed it instead of fixing it. If such information is needed,
it could be commented in include/asm-generic/Kbuild and
include/uapi/asm-generic/Kbuild.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
In old days, the "host-progs" syntax was used for specifying host
programs. It was renamed to the current "hostprogs-y" in 2004.
It is typically useful in scripts/Makefile because it allows Kbuild to
selectively compile host programs based on the kernel configuration.
This commit renames like follows:
always -> always-y
hostprogs-y -> hostprogs
So, scripts/Makefile will look like this:
always-$(CONFIG_BUILD_BIN2C) += ...
always-$(CONFIG_KALLSYMS) += ...
...
hostprogs := $(always-y) $(always-m)
I think this makes more sense because a host program is always a host
program, irrespective of the kernel configuration. We want to specify
which ones to compile by CONFIG options, so always-y will be handier.
The "always", "hostprogs-y", "hostprogs-m" will be kept for backward
compatibility for a while.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The difference between "always" and "extra-y" is that the targets
listed in $(always) are always built, whereas the ones in $(extra-y)
are built only when KBUILD_BUILTIN is set.
So, "make modules" does not build the targets in $(extra-y).
vmlinux.lds is only needed for linking vmlinux. So, adding it to extra-y
is more correct. In fact, arch/x86/kernel/Makefile does this.
Fix the example code.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Kbuild descends into a directory by either 'y' or 'm', but there is an
important difference.
Kbuild combines the built-in objects into built-in.a in each directory.
The built-in.a in the directory visited by obj-y is merged into the
built-in.a in the parent directory. This merge happens recursively
when Kbuild is ascending back towards the top directory, then built-in
objects are linked into vmlinux eventually. This works properly only
when the Makefile specifying obj-y is reachable by the chain of obj-y.
On the other hand, Kbuild does not take built-in.a from the directory
visited by obj-m. This it, all the objects in that directory are
supposed to be modular. If Kbuild descends into a directory by obj-m,
but the Makefile in the sub-directory specifies obj-y, those objects
are just left orphan.
The current statement "Kbuild only uses this information to decide that
it needs to visit the directory" is misleading. Clarify the difference.
Reported-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Johan Hovold <johan@kernel.org>
There are both positive and negative options about this feature.
At first, I thought it was a good idea, but actually Linus stated a
negative opinion (https://lkml.org/lkml/2019/9/29/227). I admit it
is ugly and annoying.
The baseline I'd like to keep is the compile-test of uapi headers.
(Otherwise, kernel developers have no way to ensure the correctness
of the exported headers.)
I will maintain a small build rule in usr/include/Makefile.
Remove the other header test functionality.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Commit 40df759e2b ("kbuild: Fix build with binutils <= 2.19")
introduced ar-option and KBUILD_ARFLAGS to deal with old binutils.
According to Documentation/process/changes.rst, the current minimal
supported version of binutils is 2.21 so you can assume the 'D' option
is always supported. Not only GNU ar but also llvm-ar supports it.
With the 'D' option hard-coded, there is no more user of ar-option
or KBUILD_ARFLAGS.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
These flags were added by commit 61754c1875 ("kbuild: Allow arch
Makefiles to override {cpp,ld,c}flags") to allow ARC to override -O2.
We did not see any other usage after all. Now that ARC switched to
CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3, there is no more user of
these variables.
Signed-off-by: Masahiro 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: Masahiro Yamada <yamada.masahiro@socionext.com>
Commit 055efab312 ("kbuild: drop support for cc-ldoption") correctly
removed the cc-ldoption from Documentation/kbuild/makefiles.txt, but
commit cd238effef ("docs: kbuild: convert docs to ReST and rename
to *.rst") revived it. I guess it was a rebase mistake.
Remove it again.
Fixes: cd238effef ("docs: kbuild: convert docs to ReST and rename to *.rst")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
I see the following warnings when I open this document with a ReST
viewer, retext:
/home/masahiro/ref/linux/Documentation/kbuild/makefiles.rst:1142: (WARNING/2) Inline emphasis start-string without end-string.
/home/masahiro/ref/linux/Documentation/kbuild/makefiles.rst:1152: (WARNING/2) Inline emphasis start-string without end-string.
/home/masahiro/ref/linux/Documentation/kbuild/makefiles.rst:1154: (WARNING/2) Inline emphasis start-string without end-string.
These hunks were added by commit e846f0dc57 ("kbuild: add support
for ensuring headers are self-contained") and commit 1e21cbfada
("kbuild: support header-test-pattern-y"), respectively. They were
written not for ReST but for the plain text, and merged via the
kbuild tree.
In the same development cycle, this document was converted to ReST
by commit cd238effef ("docs: kbuild: convert docs to ReST and rename
to *.rst"), and merged via the doc sub-system.
Merging them together into Linus' tree resulted in the current situation.
To fix the syntax, surround the asterisks with back-quotes, and
use :: for the code sample.
Fixes: 39ceda5ce1 ("Merge tag 'kbuild-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
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: Masahiro Yamada <yamada.masahiro@socionext.com>
These three variables are not intended to be tweaked by users.
Move them from kbuild.rst to makefiles.rst.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
'make clean' descends into ./Kbuild, but does not clean anything
since everything is added to no-clean-files.
There is no need to descend to ./Kbuild in the first place.
We can drop the no-clean-files assignment.
With this, there is no more user of no-clean-files. I will keep it
for a while to see whether a new user will appear.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
- match the directory structure of the linux-libc-dev package to that of
Debian-based distributions
- fix incorrect include/config/auto.conf generation when Kconfig creates
it along with the .config file
- remove misleading $(AS) from documents
- clean up precious tag files by distclean instead of mrproper
- add a new coccinelle patch for devm_platform_ioremap_resource migration
- refactor module-related scripts to read modules.order instead of
$(MODVERDIR)/*.mod files to get the list of created modules
- remove MODVERDIR
- update list of header compile-test
- add -fcf-protection=none flag to avoid conflict with the retpoline
flags when CONFIG_RETPOLINE=y
- misc cleanups
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Merge tag 'kbuild-v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull more Kbuild updates from Masahiro Yamada:
- match the directory structure of the linux-libc-dev package to that
of Debian-based distributions
- fix incorrect include/config/auto.conf generation when Kconfig
creates it along with the .config file
- remove misleading $(AS) from documents
- clean up precious tag files by distclean instead of mrproper
- add a new coccinelle patch for devm_platform_ioremap_resource
migration
- refactor module-related scripts to read modules.order instead of
$(MODVERDIR)/*.mod files to get the list of created modules
- remove MODVERDIR
- update list of header compile-test
- add -fcf-protection=none flag to avoid conflict with the retpoline
flags when CONFIG_RETPOLINE=y
- misc cleanups
* tag 'kbuild-v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits)
kbuild: add -fcf-protection=none when using retpoline flags
kbuild: update compile-test header list for v5.3-rc1
kbuild: split out *.mod out of {single,multi}-used-m rules
kbuild: remove 'prepare1' target
kbuild: remove the first line of *.mod files
kbuild: create *.mod with full directory path and remove MODVERDIR
kbuild: export_report: read modules.order instead of .tmp_versions/*.mod
kbuild: modpost: read modules.order instead of $(MODVERDIR)/*.mod
kbuild: modsign: read modules.order instead of $(MODVERDIR)/*.mod
kbuild: modinst: read modules.order instead of $(MODVERDIR)/*.mod
scsi: remove pointless $(MODVERDIR)/$(obj)/53c700.ver
kbuild: remove duplication from modules.order in sub-directories
kbuild: get rid of kernel/ prefix from in-tree modules.{order,builtin}
kbuild: do not create empty modules.order in the prepare stage
coccinelle: api: add devm_platform_ioremap_resource script
kbuild: compile-test headers listed in header-test-m as well
kbuild: remove unused hostcc-option
kbuild: remove tag files by distclean instead of mrproper
kbuild: add --hash-style= and --build-id unconditionally
kbuild: get rid of misleading $(AS) from documents
...
The assembler files in the kernel are *.S instead of *.s, so they must
be preprocessed. Since 'as' of GNU binutils is not able to preprocess,
we always use $(CC) as an assembler driver.
$(AS) is almost unused in Kbuild. As of v5.2, there is just one place
that directly invokes $(AS).
$ git grep -e '$(AS)' -e '${AS}' -e '$AS' -e '$(AS:' -e '${AS:' -- :^Documentation
drivers/net/wan/Makefile: AS68K = $(AS)
The documentation about *_AFLAGS* sounds like the flags were passed
to $(AS). This is somewhat misleading.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
The tag ".. include" should be replaced by ".. literalinclude" at
issues.rst, otherwise it causes TeX to crash due to excessive usage
of stack with Sphinx 2.0.
While here, solve a few minor issues at the kbuild book output by
adding extra blank lines.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
- remove headers_{install,check}_all targets
- remove unreasonable 'depends on !UML' from CONFIG_SAMPLES
- re-implement 'make headers_install' more cleanly
- add new header-test-y syntax to compile-test headers
- compile-test exported headers to ensure they are compilable in
user-space
- compile-test headers under include/ to ensure they are self-contained
- remove -Waggregate-return, -Wno-uninitialized, -Wno-unused-value flags
- add -Werror=unknown-warning-option for Clang
- add 128-bit built-in types support to genksyms
- fix missed rebuild of modules.builtin
- propagate 'No space left on device' error in fixdep to Make
- allow Clang to use its integrated assembler
- improve some coccinelle scripts
- add a new flag KBUILD_ABS_SRCTREE to request Kbuild to use absolute
path for $(srctree).
- do not ignore errors when compression utility is missing
- misc cleanups
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Merge tag 'kbuild-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- remove headers_{install,check}_all targets
- remove unreasonable 'depends on !UML' from CONFIG_SAMPLES
- re-implement 'make headers_install' more cleanly
- add new header-test-y syntax to compile-test headers
- compile-test exported headers to ensure they are compilable in
user-space
- compile-test headers under include/ to ensure they are self-contained
- remove -Waggregate-return, -Wno-uninitialized, -Wno-unused-value
flags
- add -Werror=unknown-warning-option for Clang
- add 128-bit built-in types support to genksyms
- fix missed rebuild of modules.builtin
- propagate 'No space left on device' error in fixdep to Make
- allow Clang to use its integrated assembler
- improve some coccinelle scripts
- add a new flag KBUILD_ABS_SRCTREE to request Kbuild to use absolute
path for $(srctree).
- do not ignore errors when compression utility is missing
- misc cleanups
* tag 'kbuild-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (49 commits)
kbuild: use -- separater intead of $(filter-out ...) for cc-cross-prefix
kbuild: Inform user to pass ARCH= for make mrproper
kbuild: fix compression errors getting ignored
kbuild: add a flag to force absolute path for srctree
kbuild: replace KBUILD_SRCTREE with boolean building_out_of_srctree
kbuild: remove src and obj from the top Makefile
scripts/tags.sh: remove unused environment variables from comments
scripts/tags.sh: drop SUBARCH support for ARM
kbuild: compile-test kernel headers to ensure they are self-contained
kheaders: include only headers into kheaders_data.tar.xz
kheaders: remove meaningless -R option of 'ls'
kbuild: support header-test-pattern-y
kbuild: do not create wrappers for header-test-y
kbuild: compile-test exported headers to ensure they are self-contained
init/Kconfig: add CONFIG_CC_CAN_LINK
kallsyms: exclude kasan local symbols on s390
kbuild: add more hints about SUBDIRS replacement
coccinelle: api/stream_open: treat all wait_.*() calls as blocking
coccinelle: put_device: Add a cast to an expression for an assignment
coccinelle: put_device: Adjust a message construction
...
The kbuild documentation clearly shows that the documents
there are written at different times: some use markdown,
some use their own peculiar logic to split sections.
Convert everything to ReST without affecting too much
the author's style and avoiding adding uneeded markups.
The conversion is actually:
- add blank lines and identation in order to identify paragraphs;
- fix tables markups;
- add some lists markups;
- mark literal blocks;
- adjust title markups.
At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
