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2019-03-17kbuild: force all architectures except um to include mandatory-yMasahiro Yamada
Currently, every arch/*/include/uapi/asm/Kbuild explicitly includes the common Kbuild.asm file. Factor out the duplicated include directives to scripts/Makefile.asm-generic so that no architecture would opt out of the mandatory-y mechanism. um is not forced to include mandatory-y since it is a very exceptional case which does not support UAPI. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-03-04kbuild: remove cc-version macroMasahiro Yamada
There is no more direct user of this macro; it is only used by cc-ifversion. Calling this macro is not efficient since it invokes the compiler to get the compiler version. CONFIG_GCC_VERSION is already calculated in the Kconfig stage, so Makefile can reuse it. Here is a note about the slight difference between cc-version and CONFIG_GCC_VERSION: When using Clang, cc-version is evaluated to '0402' because Clang defines __GNUC__ and __GNUC__MINOR__, and looks like GCC 4.2 in the version point of view. On the other hand, CONFIG_GCC_VERSION=0 when $(CC) is clang. There are currently two users of cc-ifversion: arch/mips/loongson64/Platform arch/powerpc/Makefile They are not affected by this change. The format of cc-version is <major><minor>, while CONFIG_GCC_VERSION <major><minor><patch>. I adjusted cc-ifversion for the difference of the number of digits. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-02-20kbuild: turn '/' into an alias of './'Masahiro Yamada
Commit 06300b21f4c7 ("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>
2019-01-28kbuild: merge KBUILD_VMLINUX_{INIT,MAIN} into KBUILD_VMLINUX_OBJSMasahiro Yamada
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>
2019-01-28kbuild: remove top-level built-in.aMasahiro Yamada
The symbol table in the final archive is unneeded; the linker does not require the symbol table after the --whole-archive option. Every object file in the archive is included in the link anyway. Pass thin archives from subdirectories directly to the linker, and remove the final archiving step. Fix up the document and comments as well. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Nicholas Piggin <npiggin@gmail.com>
2019-01-06kbuild: generate asm-generic wrappers if mandatory headers are missingMasahiro Yamada
Some time ago, Sam pointed out a certain degree of overwrap between generic-y and mandatory-y. (https://lkml.org/lkml/2017/7/10/121) I tweaked the meaning of mandatory-y a little bit; now it defines the minimum set of ASM headers that all architectures must have. If arch does not have specific implementation of a mandatory header, Kbuild will let it fallback to the asm-generic one by automatically generating a wrapper. This will allow to drop lots of redundant generic-y defines. Previously, "mandatory" was used in the context of UAPI, but I guess this can be extended to kernel space ASM headers. Suggested-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Sam Ravnborg <sam@ravnborg.org>
2018-12-01kbuild: announce removal of SUBDIRS if usedMasahiro Yamada
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
2018-11-02kbuild: remove unused cc-fullversion variableMasahiro Yamada
The last user of cc-fullversion was removed by commit f2910f0e6835 ("powerpc: remove old GCC version checks"). Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-09-09Drop all 00-INDEX files from Documentation/Henrik Austad
This is a respin with a wider audience (all that get_maintainer returned) and I know this spams a *lot* of people. Not sure what would be the correct way, so my apologies for ruining your inbox. The 00-INDEX files are supposed to give a summary of all files present in a directory, but these files are horribly out of date and their usefulness is brought into question. Often a simple "ls" would reveal the same information as the filenames are generally quite descriptive as a short introduction to what the file covers (it should not surprise anyone what Documentation/sched/sched-design-CFS.txt covers) A few years back it was mentioned that these files were no longer really needed, and they have since then grown further out of date, so perhaps it is time to just throw them out. A short status yields the following _outdated_ 00-INDEX files, first counter is files listed in 00-INDEX but missing in the directory, last is files present but not listed in 00-INDEX. List of outdated 00-INDEX: Documentation: (4/10) Documentation/sysctl: (0/1) Documentation/timers: (1/0) Documentation/blockdev: (3/1) Documentation/w1/slaves: (0/1) Documentation/locking: (0/1) Documentation/devicetree: (0/5) Documentation/power: (1/1) Documentation/powerpc: (0/5) Documentation/arm: (1/0) Documentation/x86: (0/9) Documentation/x86/x86_64: (1/1) Documentation/scsi: (4/4) Documentation/filesystems: (2/9) Documentation/filesystems/nfs: (0/2) Documentation/cgroup-v1: (0/2) Documentation/kbuild: (0/4) Documentation/spi: (1/0) Documentation/virtual/kvm: (1/0) Documentation/scheduler: (0/2) Documentation/fb: (0/1) Documentation/block: (0/1) Documentation/networking: (6/37) Documentation/vm: (1/3) Then there are 364 subdirectories in Documentation/ with several files that are missing 00-INDEX alltogether (and another 120 with a single file and no 00-INDEX). I don't really have an opinion to whether or not we /should/ have 00-INDEX, but the above 00-INDEX should either be removed or be kept up to date. If we should keep the files, I can try to keep them updated, but I rather not if we just want to delete them anyway. As a starting point, remove all index-files and references to 00-INDEX and see where the discussion is going. Signed-off-by: Henrik Austad <henrik@austad.us> Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Just-do-it-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Acked-by: Paul Moore <paul@paul-moore.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: [Almost everybody else] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-08-22kbuild: Fix LOADLIBES rename in Documentation/kbuild/makefiles.txtMichal Suchanek
Fixes: 8377bd2b9ee1 ("kbuild: Rename HOST_LOADLIBES to KBUILD_HOSTLDLIBS") Signed-off-by: Michal Suchanek <msuchanek@suse.de> Acked-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-08-22kconfig: report recursive dependency involving 'imply'Masahiro Yamada
Currently, Kconfig does not complain about the recursive dependency where 'imply' keywords are involved. [Test Code] config A bool "a" config B bool "b" imply A depends on A In the code above, Kconfig cannot calculate the symbol values correctly due to the circular dependency. For example, allyesconfig followed by syncconfig results in an odd behavior because CONFIG_B becomes visible in syncconfig. $ make allyesconfig scripts/kconfig/conf --allyesconfig Kconfig # # configuration written to .config # $ cat .config # # Automatically generated file; DO NOT EDIT. # Main menu # CONFIG_A=y $ make syncconfig scripts/kconfig/conf --syncconfig Kconfig * * Restart config... * * * Main menu * a (A) [Y/n/?] y b (B) [N/y/?] (NEW) To detect this correctly, sym_check_expr_deps() should recurse to not only sym->rev_dep.expr but also sym->implied.expr . At this moment, sym_check_print_recursive() cannot distinguish 'select' and 'imply' since it does not know the precise context where the recursive dependency has been hit. This will be solved by the next commit. In fact, even the document and the unit-test are confused. Using 'imply' does not solve recursive dependency since 'imply' addresses the unmet direct dependency, which 'select' could cause. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Tested-by: Dirk Gouders <dirk@gouders.net>
2018-08-15Merge tag 'kconfig-v4.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kconfig updates from Masahiro Yamada: - show clearer error messages where pkg-config is needed, but not installed - rename SYMBOL_AUTO to SYMBOL_NO_WRITE to reflect its semantics - create all necessary directories by Kconfig tool itself instead of Makefile - update the .config unconditionally when syncconfig is invoked - use 'include' directive instead of '-include' where include/config/{auto,tristate}.conf is mandatory - do not try to update the .config when running install targets - add .DELETE_ON_ERROR to delete partially updated files - misc cleanups and fixes * tag 'kconfig-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kconfig: remove P_ENV property type kconfig: remove unused sym_get_env_prop() function kconfig: fix the rule of mainmenu_stmt symbol init/Kconfig: Use short unix-style option instead of --longname Kbuild: Makefile.modbuiltin: include auto.conf and tristate.conf mandatory kbuild: remove auto.conf from prerequisite of phony targets kbuild: do not update config for 'make kernelrelease' kbuild: do not update config when running install targets kbuild: add .DELETE_ON_ERROR special target kbuild: use 'include' directive to load auto.conf from top Makefile kconfig: allow all config targets to write auto.conf if missing kconfig: make syncconfig update .config regardless of sym_change_count kconfig: create directories needed for syncconfig by itself kconfig: remove unneeded directory generation from local*config kconfig: split out useful helpers in confdata.c kconfig: rename file_write_dep and move it to confdata.c kconfig: fix typos in description of "choice" in kconfig-language.txt kconfig: handle format string before calling conf_message_callback() kconfig: rename SYMBOL_AUTO to SYMBOL_NO_WRITE kconfig: check for pkg-config on make {menu,n,g,x}config
2018-07-25kconfig: fix typos in description of "choice" in kconfig-language.txtRandy Dunlap
Fix a couple of punctuation "typos" in the description of the "choice" keyword. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-07-21kbuild: if_changed: document single use per target limitationDirk Gouders
Users of if_changed could easily feel invited to use it to divide a recipe into parts like: a: prereq FORCE $(call if_changed,do_a) $(call if_changed,do_b) But this is problematic, because if_changed should not be used more than once per target: in the above example, if_changed stores the command-line of the given command in .a.cmd and when a is up-to-date with respect to prereq, the file .a.cmd contains the command-line for the last command executed, i.e. do_b. When the recipe is then executed again, without any change of prerequisites, the command-line check for do_a will fail, do_a will be executed and stored in .a.cmd. The next check, however, will still see the old content (the file isn't re-read) and if_changed will skip do_b, because the command-line test will not recognize a change. On the next execution of the recipe the roles will flip: do_a is OK but do_b not and it will be executed. And so on... Signed-off-by: Dirk Gouders <dirk@gouders.net> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-07-18kbuild: Use HOST*FLAGS options from the command lineLaura Abbott
Now that we have the rename in place, reuse the HOST*FLAGS options as something that can be set from the command line and included with the rest of the flags. Signed-off-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-07-18kbuild: Rename HOSTCFLAGS to KBUILD_HOSTCFLAGSLaura Abbott
In preparation for enabling command line CFLAGS, re-name HOSTCFLAGS to KBUILD_HOSTCFLAGS as the internal use only flags. This should not have any visible effects. Signed-off-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-07-06kbuild: document the KBUILD_KCONFIG env. variableRandy Dunlap
Add usage info for the Kbuild environment variable KBUILD_KCONFIG. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Cao jin <caoj.fnst@cn.fujitsu.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-07-06kconfig: update user kconfig tools doc.Randy Dunlap
Update Documentation/kbuild/kconfig.txt, which mostly contains user help for using the kernel config tools. - Add mention of 'nconfig' embedded help text. - Make the section on new config symbols readable. - Correct how to find menuconfig search help. - Add section on 'nconfig' usage. - Mention that gconfig has multiple viewing modes/options. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-07-06kbuild: delete INSTALL_FW_PATH from kbuild documentationRandy Dunlap
Removed Kbuild documentation for INSTALL_FW_PATH. The kbuild symbol INSTALL_FW_PATH was removed from Kbuild tools in September 2017 (for 4.14) but the symbol was not deleted from the kbuild documentation, so do that now. Fixes: 5620a0d1aacd ("firmware: delete in-kernel firmware") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: stable@vger.kernel.org # 4.14+ Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-07-06kbuild: update ARCH alias info for sparcRandy Dunlap
The supported alias for building sparc 32-bit is "sparc32", not "sparc", so update the alias documentation for that. Just using "sparc" produces a 64-bit config file. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-07-06kbuild: update ARCH alias info for shRandy Dunlap
In Kbuild documentation, add alias for 64-bit sh ARCH ("sh64") to the list of ARCH aliases. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-06-25kconfig: document Kconfig source file commentsRandy Dunlap
I saw this type of Kconfig construct on LKML: config SYMBOOL #bool "prompt string" default y and wondered what it does. Then I wondered if '#' comments are even documented. They aren't, so add a little doc for that. Ah, good. kconfig says: arch/x86/Kconfig:2942:warning: config symbol defined without type Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-06-14Kbuild: rename CC_STACKPROTECTOR[_STRONG] config variablesLinus Torvalds
The changes to automatically test for working stack protector compiler support in the Kconfig files removed the special STACKPROTECTOR_AUTO option that picked the strongest stack protector that the compiler supported. That was all a nice cleanup - it makes no sense to have the AUTO case now that the Kconfig phase can just determine the compiler support directly. HOWEVER. It also meant that doing "make oldconfig" would now _disable_ the strong stackprotector if you had AUTO enabled, because in a legacy config file, the sane stack protector configuration would look like CONFIG_HAVE_CC_STACKPROTECTOR=y # CONFIG_CC_STACKPROTECTOR_NONE is not set # CONFIG_CC_STACKPROTECTOR_REGULAR is not set # CONFIG_CC_STACKPROTECTOR_STRONG is not set CONFIG_CC_STACKPROTECTOR_AUTO=y and when you ran this through "make oldconfig" with the Kbuild changes, it would ask you about the regular CONFIG_CC_STACKPROTECTOR (that had been renamed from CONFIG_CC_STACKPROTECTOR_REGULAR to just CONFIG_CC_STACKPROTECTOR), but it would think that the STRONG version used to be disabled (because it was really enabled by AUTO), and would disable it in the new config, resulting in: CONFIG_HAVE_CC_STACKPROTECTOR=y CONFIG_CC_HAS_STACKPROTECTOR_NONE=y CONFIG_CC_STACKPROTECTOR=y # CONFIG_CC_STACKPROTECTOR_STRONG is not set CONFIG_CC_HAS_SANE_STACKPROTECTOR=y That's dangerously subtle - people could suddenly find themselves with the weaker stack protector setup without even realizing. The solution here is to just rename not just the old RECULAR stack protector option, but also the strong one. This does that by just removing the CC_ prefix entirely for the user choices, because it really is not about the compiler support (the compiler support now instead automatially impacts _visibility_ of the options to users). This results in "make oldconfig" actually asking the user for their choice, so that we don't have any silent subtle security model changes. The end result would generally look like this: CONFIG_HAVE_CC_STACKPROTECTOR=y CONFIG_CC_HAS_STACKPROTECTOR_NONE=y CONFIG_STACKPROTECTOR=y CONFIG_STACKPROTECTOR_STRONG=y CONFIG_CC_HAS_SANE_STACKPROTECTOR=y where the "CC_" versions really are about internal compiler infrastructure, not the user selections. Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-11Documentation: kconfig: add recommended way to describe compiler supportMasahiro Yamada
It would be nice if the source code is written in the same style. This proposes the convention for describing the compiler capability in Kconfig. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-05-29Documentation: kconfig: document a new Kconfig macro languageMasahiro Yamada
Add a document for the macro language introduced to Kconfig. The motivation of this work is to move the compiler option tests to Kconfig from Makefile. A number of kernel features require the compiler support. Enabling such features blindly in Kconfig ends up with a lot of nasty build-time testing in Makefiles. If a chosen feature turns out unsupported by the compiler, what the build system can do is either to disable it (silently!) or to forcibly break the build, despite Kconfig has let the user to enable it. By moving the compiler capability tests to Kconfig, features unsupported by the compiler will be hidden automatically. This change was strongly prompted by Linus Torvalds. You can find his suggestions [1] [2] in ML. The original idea was to add a new attribute with 'option shell=...', but I found more generalized text expansion would make Kconfig more powerful and lovely. The basic ideas are from Make, but there are some differences. [1]: https://lkml.org/lkml/2016/12/9/577 [2]: https://lkml.org/lkml/2018/2/7/527 Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
2018-05-29kconfig: reference environment variables directly and remove 'option env='Masahiro Yamada
To get access to environment variables, Kconfig needs to define a symbol using "option env=" syntax. It is tedious to add a symbol entry for each environment variable given that we need to define much more such as 'CC', 'AS', 'srctree' etc. to evaluate the compiler capability in Kconfig. Adding '$' for symbol references is grammatically inconsistent. Looking at the code, the symbols prefixed with 'S' are expanded by: - conf_expand_value() This is used to expand 'arch/$ARCH/defconfig' and 'defconfig_list' - sym_expand_string_value() This is used to expand strings in 'source' and 'mainmenu' All of them are fixed values independent of user configuration. So, they can be changed into the direct expansion instead of symbols. This change makes the code much cleaner. The bounce symbols 'SRCARCH', 'ARCH', 'SUBARCH', 'KERNELVERSION' are gone. sym_init() hard-coding 'UNAME_RELEASE' is also gone. 'UNAME_RELEASE' should be replaced with an environment variable. ARCH_DEFCONFIG is a normal symbol, so it should be simply referenced without '$' prefix. The new syntax is addicted by Make. The variable reference needs parentheses, like $(FOO), but you can omit them for single-letter variables, like $F. Yet, in Makefiles, people tend to use the parenthetical form for consistency / clarification. At this moment, only the environment variable is supported, but I will extend the concept of 'variable' later on. The variables are expanded in the lexer so we can simplify the token handling on the parser side. For example, the following code works. [Example code] config MY_TOOLCHAIN_LIST string default "My tools: CC=$(CC), AS=$(AS), CPP=$(CPP)" [Result] $ make -s alldefconfig && tail -n 1 .config CONFIG_MY_TOOLCHAIN_LIST="My tools: CC=gcc, AS=as, CPP=gcc -E" Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Kees Cook <keescook@chromium.org>
2018-04-03Merge tag 'kconfig-v4.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kconfig updates from Masahiro Yamada: - improve checkpatch for more precise Kconfig code checking - clarify effective selects by grouping reverse dependencies in help - do not write out '# CONFIG_FOO is not set' from invisible symbols - make oldconfig as silent as it should be - rename 'silentoldconfig' to 'syncconfig' - add unit-test framework and several test cases - warn unmet dependency of tristate symbols - make unmet dependency warnings readable, removing false positives - improve recursive include detection - use yylineno to simplify the line number tracking - misc cleanups * tag 'kconfig-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (30 commits) kconfig: use yylineno option instead of manual lineno increments kconfig: detect recursive inclusion earlier kconfig: remove duplicated file name and lineno of recursive inclusion kconfig: do not include both curses.h and ncurses.h for nconfig kconfig: make unmet dependency warnings readable kconfig: warn unmet direct dependency of tristate symbols selected by y kconfig: tests: test if recursive inclusion is detected kconfig: tests: test if recursive dependencies are detected kconfig: tests: test randconfig for choice in choice kconfig: tests: test defconfig when two choices interact kconfig: tests: check visibility of tristate choice values in y choice kconfig: tests: check unneeded "is not set" with unmet dependency kconfig: tests: test if new symbols in choice are asked kconfig: tests: test automatic submenu creation kconfig: tests: add basic choice tests kconfig: tests: add framework for Kconfig unit testing kbuild: add PYTHON2 and PYTHON3 variables kconfig: remove redundant streamline_config.pl prerequisite kconfig: rename silentoldconfig to syncconfig kconfig: invoke oldconfig instead of silentoldconfig from local*config ...
2018-03-26kconfig: rename silentoldconfig to syncconfigMasahiro Yamada
As commit cedd55d49dee ("kconfig: Remove silentoldconfig from help and docs; fix kconfig/conf's help") mentioned, 'silentoldconfig' is a historical misnomer. That commit removed it from help and docs since it is an internal interface. If so, it should be allowed to rename it to something more intuitive. 'syncconfig' is the one I came up with because it updates the .config if necessary, then synchronize include/generated/autoconf.h and include/config/* with it. You should not manually invoke 'silentoldcofig'. Display warning if used in case existing scripts are doing wrong. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-26kbuild: remove internally used LDFLAGS_vmlinux from kbuild.txtMasahiro Yamada
Documentation/kbuild/makefiles.txt lists variables used in Makefile whereas Documentation/kbuild/kbuild.txt describes user assignable parameters given via environments or the command line. The top Makefile and arch/*/Makefile accumulate proper linker flags to LDFLAGS_vmlinux. So, users can not override it from the command line. Generally, per-file options are not supposed to be user-assignable. Remove the misleading entry from kbuild.txt. If we need a way to append user-specific flags for linking the kernel, LDFLAGS_KERNEL would be a consistent choice because we already expose LDFLAGS_MODULE counter-part to users. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26kbuild: remove command line interface LDFLAGS_MODULE from makefiles.txtMasahiro Yamada
Documentation/kbuild/makefiles.txt lists variables used in Makefile whereas Documentation/kbuild/kbuild.txt describes user assignable parameters given via environments or the command line. LDFLAGS_MODULE is a command line interface, so it should be dropped from makefiles.txt. Some lines below in this file, it is clearly explained that KBUILD_LDFLAGS_MODULE is the right one for the internal use: KBUILD_LDFLAGS_MODULE Options for $(LD) when linking modules $(KBUILD_LDFLAGS_MODULE) is used to add arch-specific options used when linking modules. This is often a linker script. From commandline LDFLAGS_MODULE shall be used (see kbuild.txt). Then, kbuild.txt explains LDFLAGS_MODULE, like follows: LDFLAGS_MODULE -------------------------------------------------- Additional options used for $(LD) when linking modules. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26kbuild: rename built-in.o to built-in.aNicholas Piggin
Incremental linking is gone, so rename built-in.o to built-in.a, which is the usual extension for archive files. This patch does two things, first is a simple search/replace: git grep -l 'built-in\.o' | xargs sed -i 's/built-in\.o/built-in\.a/g' The second is to invert nesting of nested text manipulations to avoid filtering built-in.a out from libs-y2: -libs-y2 := $(filter-out %.a, $(patsubst %/, %/built-in.a, $(libs-y))) +libs-y2 := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y))) Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26kbuild: remove incremental linking optionNicholas Piggin
This removes the old `ld -r` incremental link option, which has not been selected by any architecture since June 2017. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-31Merge tag 'docs-4.16' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "Documentation updates for 4.16. New stuff includes refcount_t documentation, errseq documentation, kernel-doc support for nested structure definitions, the removal of lots of crufty kernel-doc support for unused formats, SPDX tag documentation, the beginnings of a manual for subsystem maintainers, and lots of fixes and updates. As usual, some of the changesets reach outside of Documentation/ to effect kerneldoc comment fixes. It also adds the new LICENSES directory, of which Thomas promises I do not need to be the maintainer" * tag 'docs-4.16' of git://git.lwn.net/linux: (65 commits) linux-next: docs-rst: Fix typos in kfigure.py linux-next: DOC: HWPOISON: Fix path to debugfs in hwpoison.txt Documentation: Fix misconversion of #if docs: add index entry for networking/msg_zerocopy Documentation: security/credentials.rst: explain need to sort group_list LICENSES: Add MPL-1.1 license LICENSES: Add the GPL 1.0 license LICENSES: Add Linux syscall note exception LICENSES: Add the MIT license LICENSES: Add the BSD-3-clause "Clear" license LICENSES: Add the BSD 3-clause "New" or "Revised" License LICENSES: Add the BSD 2-clause "Simplified" license LICENSES: Add the LGPL-2.1 license LICENSES: Add the LGPL 2.0 license LICENSES: Add the GPL 2.0 license Documentation: Add license-rules.rst to describe how to properly identify file licenses scripts: kernel_doc: better handle show warnings logic fs/*/Kconfig: drop links to 404-compliant http://acl.bestbits.at doc: md: Fix a file name to md-fault.c in fault-injection.txt errseq: Add to documentation tree ...
2018-01-06kconfig: fix relational operators for bool and tristate symbolsNicolas Pitre
Since commit 31847b67bec0 ("kconfig: allow use of relations other than (in)equality") it is possible to use relational operators in Kconfig statements. However, those operators give unexpected results when applied to bool/tristate values: (n < y) = y (correct) (m < y) = y (correct) (n < m) = n (wrong) This happens because relational operators process bool and tristate symbols as strings and m sorts before n. It makes little sense to do a lexicographical compare on bool and tristate values though. Documentation/kbuild/kconfig-language.txt states that expression can have a value of 'n', 'm' or 'y' (or 0, 1, 2 respectively for calculations). Let's make it so for relational comparisons with bool/tristate expressions as well and document them. If at least one symbol is an actual string then the lexicographical compare works just as before. Signed-off-by: Nicolas Pitre <nico@linaro.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-12-11Documentation/kbuild: Add guidance for the use of defaultDarren Hart (VMware)
Document the preference [1] for new CONFIG options to "default n" (or not use default at all) in order to minimizes changes to the config, especially to avoid "make oldconfig" growing unnecessarily from release to release. Document the exceptions where it is acceptable to use "default y/m" for new CONFIG options. 1. https://lkml.org/lkml/2017/11/18/257 Cc: "Yann E. MORIN" <yann.morin.1998@free.fr> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Michal Marek <mmarek@suse.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-kbuild@vger.kernel.org Cc: linux-doc@vger.kernel.org Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-11-14Merge tag 'devicetree-for-4.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux Pull DeviceTree updates from Rob Herring: "A bigger diffstat than usual with the kbuild changes and a tree wide fix in the binding documentation. Summary: - kbuild cleanups and improvements for dtbs - Code clean-up of overlay code and fixing for some long standing memory leak and race condition in applying overlays - Improvements to DT memory usage making sysfs/kobjects optional and skipping unflattening of disabled nodes. This is part of kernel tinification efforts. - Final piece of removing storing the full path for every DT node. The prerequisite conversion of printk's to use device_node format specifier happened in 4.14. - Sync with current upstream dtc. This brings additional checks to dtb compiling. - Binding doc tree wide removal of leading 0s from examples - RTC binding documentation adding missing devices and some consolidation of duplicated bindings - Vendor prefix documentation for nutsboard, Silicon Storage Technology, shimafuji, Tecon Microprocessor Technologies, DH electronics GmbH, Opal Kelly, and Next Thing" * tag 'devicetree-for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (55 commits) dt-bindings: usb: add #phy-cells to usb-nop-xceiv dt-bindings: Remove leading zeros from bindings notation kbuild: handle dtb-y and CONFIG_OF_ALL_DTBS natively in Makefile.lib MIPS: dts: remove bogus bcm96358nb4ser.dtb from dtb-y entry kbuild: clean up *.dtb and *.dtb.S patterns from top-level Makefile .gitignore: move *.dtb and *.dtb.S patterns to the top-level .gitignore .gitignore: sort normal pattern rules alphabetically dt-bindings: add vendor prefix for Next Thing Co. scripts/dtc: Update to upstream version v1.4.5-6-gc1e55a5513e9 of: dynamic: fix memory leak related to properties of __of_node_dup of: overlay: make pr_err() string unique of: overlay: pr_err from return NOTIFY_OK to overlay apply/remove of: overlay: remove unneeded check for NULL kbasename() of: overlay: remove a dependency on device node full_name of: overlay: simplify applying symbols from an overlay of: overlay: avoid race condition between applying multiple overlays of: overlay: loosen overly strict phandle clash check of: overlay: expand check of whether overlay changeset can be removed of: overlay: detect cases where device tree may become corrupt of: overlay: minor restructuring ...
2017-11-08kbuild: clean up *.dtb and *.dtb.S patterns from top-level MakefileMasahiro Yamada
We need to add "clean-files" in Makfiles to clean up DT blobs, but we often miss to do so. Since there are no source files that end with .dtb or .dtb.S, so we can clean-up those files from the top-level Makefile. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-24kbuild doc: a bundle of fixes on makefiles.txtCao jin
It does several fixes: 1. move the displaced ld example to its reasonable place. 2. add new example for command gzip. 3. fix 2 number errors. 4. fix format of chapter 7.x, make it looks the same as other chapters. Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-08-07kbuild: Update example for ccflags-y usageSedat Dilek
Update the ccflags-y example to match current usage. Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-07-07Merge tag 'kbuild-thinar-v4.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild thin archives updates from Masahiro Yamada: "Thin archives migration by Nicholas Piggin. THIN_ARCHIVES has been available for a while as an optional feature only for PowerPC architecture, but we do not need two different intermediate-artifact schemes. Using thin archives instead of conventional incremental linking has various advantages: - save disk space for builds - speed-up building a little - fix some link issues (for example, allyesconfig on ARM) due to more flexibility for the final linking - work better with dead code elimination we are planning As discussed before, this migration has been done unconditionally so that any problems caused by this will show up with "git bisect". With testing with 0-day and linux-next, some architectures actually showed up problems, but they were trivial and all fixed now" * tag 'kbuild-thinar-v4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: tile: remove unneeded extra-y in Makefile kbuild: thin archives make default for all archs x86/um: thin archives build fix tile: thin archives fix linking ia64: thin archives fix linking sh: thin archives fix linking kbuild: handle libs-y archives separately from built-in.o archives kbuild: thin archives use P option to ar kbuild: thin archives final link close --whole-archives option ia64: remove unneeded extra-y in Makefile.gate tile: fix dependency and .*.cmd inclusion for incremental build sparc64: Use indirect calls in hamming weight stubs
2017-07-07Merge tag 'kbuild-v4.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Clean up Makefiles and scripts - Improve clang support - Remove unneeded genhdr-y syntax - Remove unneeded cc-option-align macro - Introduce __cc-option macro and use it to fix x86 boot code compiler flags * tag 'kbuild-v4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kbuild: improve comments on KBUILD_SRC x86/build: Specify stack alignment for clang x86/build: Use __cc-option for boot code compiler options kbuild: Add __cc-option macro kbuild: remove cc-option-align kbuild: replace genhdr-y with generated-y kbuild: clang: Disable 'address-of-packed-member' warning kbuild: remove duplicated arch/*/include/generated/uapi include path kbuild: speed up checksyscalls.sh kbuild: simplify silent build (-s) detection
2017-06-30kbuild: handle libs-y archives separately from built-in.o archivesNicholas Piggin
The thin archives build currently puts all lib.a and built-in.o files together and links them with --whole-archive. This works because thin archives can recursively refer to thin archives. However some architectures include libgcc.a, which may not be a thin archive, or it may not be constructed with the "P" option, in which case its contents do not get linked correctly. So don't pull .a libs into the root built-in.o archive. These libs should already have symbol tables and indexes built, so they can be direct linker inputs. Move them out of the --whole-archive option, which restore the conditional linking behaviour of lib.a to thin archives builds. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-06-25kbuild: remove cc-option-alignMasahiro Yamada
Documentation/kbuild/makefiles.txt says the change for align options occurred at GCC 3.0, and Documentation/process/changes.rst says the minimal supported GCC version is 3.2, so it should be safe to hard-code -falign* options. Fix the only user arch/x86/Makefile_32.cpu and remove cc-option-align. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Ingo Molnar <mingo@kernel.org>
2017-06-22kbuild: replace genhdr-y with generated-yMasahiro Yamada
Originally, generated-y and genhdr-y had different meaning, like follows: - generated-y: generated headers (other than asm-generic wrappers) - header-y : headers to be exported - genhdr-y : generated headers to be exported (generated-y + header-y) Since commit fcc8487d477a ("uapi: export all headers under uapi directories"), headers under UAPI directories are all exported. So, there is no more difference between generated-y and genhdr-y. We see two users of genhdr-y, arch/{arm,x86}/include/uapi/asm/Kbuild. They generate some headers in arch/{arm,x86}/include/generated/uapi/asm directories, which are obviously exported. Replace them with generated-y, and abolish genhdr-y. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
2017-05-18Documentation, kbuild: fix typo "minimun" -> "minimum"Tobias Klauser
Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-05-11uapi: export all arch specifics directoriesNicolas Dichtel
This patch removes the need of subdir-y. Now all files/directories under arch/<arch>/include/uapi/ are exported. The only change for userland is the layout of the command 'make headers_install_all': directories asm-<arch> are replaced by arch-<arch>/. Those new directories contains all files/directories of the specified arch. Note that only cris and tile have more directories than only asm: - arch-v[10|32] for cris; - arch for tile. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-05-11uapi: export all headers under uapi directoriesNicolas Dichtel
Regularly, when a new header is created in include/uapi/, the developer forgets to add it in the corresponding Kbuild file. This error is usually detected after the release is out. In fact, all headers under uapi directories should be exported, thus it's useless to have an exhaustive list. After this patch, the following files, which were not exported, are now exported (with make headers_install_all): asm-arc/kvm_para.h asm-arc/ucontext.h asm-blackfin/shmparam.h asm-blackfin/ucontext.h asm-c6x/shmparam.h asm-c6x/ucontext.h asm-cris/kvm_para.h asm-h8300/shmparam.h asm-h8300/ucontext.h asm-hexagon/shmparam.h asm-m32r/kvm_para.h asm-m68k/kvm_para.h asm-m68k/shmparam.h asm-metag/kvm_para.h asm-metag/shmparam.h asm-metag/ucontext.h asm-mips/hwcap.h asm-mips/reg.h asm-mips/ucontext.h asm-nios2/kvm_para.h asm-nios2/ucontext.h asm-openrisc/shmparam.h asm-parisc/kvm_para.h asm-powerpc/perf_regs.h asm-sh/kvm_para.h asm-sh/ucontext.h asm-tile/shmparam.h asm-unicore32/shmparam.h asm-unicore32/ucontext.h asm-x86/hwcap2.h asm-xtensa/kvm_para.h drm/armada_drm.h drm/etnaviv_drm.h drm/vgem_drm.h linux/aspeed-lpc-ctrl.h linux/auto_dev-ioctl.h linux/bcache.h linux/btrfs_tree.h linux/can/vxcan.h linux/cifs/cifs_mount.h linux/coresight-stm.h linux/cryptouser.h linux/fsmap.h linux/genwqe/genwqe_card.h linux/hash_info.h linux/kcm.h linux/kcov.h linux/kfd_ioctl.h linux/lightnvm.h linux/module.h linux/nbd-netlink.h linux/nilfs2_api.h linux/nilfs2_ondisk.h linux/nsfs.h linux/pr.h linux/qrtr.h linux/rpmsg.h linux/sched/types.h linux/sed-opal.h linux/smc.h linux/smc_diag.h linux/stm.h linux/switchtec_ioctl.h linux/vfio_ccw.h linux/wil6210_uapi.h rdma/bnxt_re-abi.h Note that I have removed from this list the files which are generated in every exported directories (like .install or .install.cmd). Thanks to Julien Floret <julien.floret@6wind.com> for the tip to get all subdirs with a pure makefile command. For the record, note that exported files for asm directories are a mix of files listed by: - include/uapi/asm-generic/Kbuild.asm; - arch/<arch>/include/uapi/asm/Kbuild; - arch/<arch>/include/asm/Kbuild. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Mark Salter <msalter@redhat.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-05-11Makefile.headersinst: remove destination-y optionNicolas Dichtel
This option was added in commit c7bb349e7c25 ("kbuild: introduce destination-y for exported headers") but never used in-tree. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Acked-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2016-11-16Kconfig: Introduce the "imply" keywordNicolas Pitre
The "imply" keyword is a weak version of "select" where the target config symbol can still be turned off, avoiding those pitfalls that come with the "select" keyword. This is useful e.g. with multiple drivers that want to indicate their ability to hook into a secondary subsystem while allowing the user to configure that subsystem out without also having to unset these drivers. Currently, the same effect can almost be achieved with: config DRIVER_A tristate config DRIVER_B tristate config DRIVER_C tristate config DRIVER_D tristate [...] config SUBSYSTEM_X tristate default DRIVER_A || DRIVER_B || DRIVER_C || DRIVER_D || [...] This is unwieldy to maintain especially with a large number of drivers. Furthermore, there is no easy way to restrict the choice for SUBSYSTEM_X to y or n, excluding m, when some drivers are built-in. The "select" keyword allows for excluding m, but it excludes n as well. Hence this "imply" keyword. The above becomes: config DRIVER_A tristate imply SUBSYSTEM_X config DRIVER_B tristate imply SUBSYSTEM_X [...] config SUBSYSTEM_X tristate This is much cleaner, and way more flexible than "select". SUBSYSTEM_X can still be configured out, and it can be set as a module when none of the drivers are configured in or all of them are modular. Signed-off-by: Nicolas Pitre <nico@linaro.org> Acked-by: Richard Cochran <richardcochran@gmail.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <john.stultz@linaro.org> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Cc: Paul Bolle <pebolle@tiscali.nl> Cc: linux-kbuild@vger.kernel.org Cc: netdev@vger.kernel.org Cc: Michal Marek <mmarek@suse.com> Cc: Edward Cree <ecree@solarflare.com> Link: http://lkml.kernel.org/r/1478841010-28605-2-git-send-email-nicolas.pitre@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-10-14Merge branch 'kbuild' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild Pull kbuild updates from Michal Marek: - EXPORT_SYMBOL for asm source by Al Viro. This does bring a regression, because genksyms no longer generates checksums for these symbols (CONFIG_MODVERSIONS). Nick Piggin is working on a patch to fix this. Plus, we are talking about functions like strcpy(), which rarely change prototypes. - Fixes for PPC fallout of the above by Stephen Rothwell and Nick Piggin - fixdep speedup by Alexey Dobriyan. - preparatory work by Nick Piggin to allow architectures to build with -ffunction-sections, -fdata-sections and --gc-sections - CONFIG_THIN_ARCHIVES support by Stephen Rothwell - fix for filenames with colons in the initramfs source by me. * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (22 commits) initramfs: Escape colons in depfile ppc: there is no clear_pages to export powerpc/64: whitelist unresolved modversions CRCs kbuild: -ffunction-sections fix for archs with conflicting sections kbuild: add arch specific post-link Makefile kbuild: allow archs to select link dead code/data elimination kbuild: allow architectures to use thin archives instead of ld -r kbuild: Regenerate genksyms lexer kbuild: genksyms fix for typeof handling fixdep: faster CONFIG_ search ia64: move exports to definitions sparc32: debride memcpy.S a bit [sparc] unify 32bit and 64bit string.h sparc: move exports to definitions ppc: move exports to definitions arm: move exports to definitions s390: move exports to definitions m68k: move exports to definitions alpha: move exports to actual definitions x86: move exports to actual definitions ...