While watching Michael's new talk on Clang-built-Linux, I noticed the
arch table in our docs that he refers to is outdated.
Add hexagon and User Mode. Bump MIPS and RISCV to LLVM=1. PowerPC is
almost LLVM=1 capable; ppc64le works, but ppc64 (big endian) and ppc32
still need more work.
Link: https://youtu.be/W4zdEDpvR5c?t=399
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
- Add HOSTPKG_CONFIG env variable to allow users to override pkg-config
- Support W=e as a shorthand for KCFLAGS=-Werror
- Fix CONFIG_IKHEADERS build to support toybox cpio
- Add scripts/dummy-tools/pahole to ease distro packagers' life
- Suppress false-positive warnings from checksyscalls.sh for W=2 build
- Factor out the common code of arch/*/boot/install.sh into
scripts/install.sh
- Support 'kernel-install' tool in scripts/prune-kernel
- Refactor module-versioning to link the symbol versions at the final
link of vmlinux and modules
- Remove CONFIG_MODULE_REL_CRCS because module-versioning now works in
an arch-agnostic way
- Refactor modpost, Makefiles
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Merge tag 'kbuild-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- Add HOSTPKG_CONFIG env variable to allow users to override pkg-config
- Support W=e as a shorthand for KCFLAGS=-Werror
- Fix CONFIG_IKHEADERS build to support toybox cpio
- Add scripts/dummy-tools/pahole to ease distro packagers' life
- Suppress false-positive warnings from checksyscalls.sh for W=2 build
- Factor out the common code of arch/*/boot/install.sh into
scripts/install.sh
- Support 'kernel-install' tool in scripts/prune-kernel
- Refactor module-versioning to link the symbol versions at the final
link of vmlinux and modules
- Remove CONFIG_MODULE_REL_CRCS because module-versioning now works in
an arch-agnostic way
- Refactor modpost, Makefiles
* tag 'kbuild-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (56 commits)
genksyms: adjust the output format to modpost
kbuild: stop merging *.symversions
kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS
modpost: extract symbol versions from *.cmd files
modpost: add sym_find_with_module() helper
modpost: change the license of EXPORT_SYMBOL to bool type
modpost: remove left-over cross_compile declaration
kbuild: record symbol versions in *.cmd files
kbuild: generate a list of objects in vmlinux
modpost: move *.mod.c generation to write_mod_c_files()
modpost: merge add_{intree_flag,retpoline,staging_flag} to add_header
scripts/prune-kernel: Use kernel-install if available
kbuild: factor out the common installation code into scripts/install.sh
modpost: split new_symbol() to symbol allocation and hash table addition
modpost: make sym_add_exported() always allocate a new symbol
modpost: make multiple export error
modpost: dump Module.symvers in the same order of modules.order
modpost: traverse the namespace_list in order
modpost: use doubly linked list for dump_lists
modpost: traverse unresolved symbols in order
...
To enable Clang randstruct support, move the structure layout
randomization seed generation out of scripts/gcc-plugins/ into
scripts/basic/ so it happens early enough that it can be used by either
compiler implementation. The gcc-plugin still builds its own header file,
but now does so from the common "randstruct.seed" file.
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220503205503.3054173-6-keescook@chromium.org
In preparation for Clang supporting randstruct, reorganize the Kconfigs,
move the attribute macros, and generalize the feature to be named
CONFIG_RANDSTRUCT for on/off, CONFIG_RANDSTRUCT_FULL for the full
randomization mode, and CONFIG_RANDSTRUCT_PERFORMANCE for the cache-line
sized mode.
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220503205503.3054173-4-keescook@chromium.org
Add references to 1) a research paper which provides a definition of
Kconfig semantics, 2) the kismet tool, which checks for unmet direct
dependency bugs in Kconfig specifications.
Signed-off-by: Paul Gazzillo <paul@pgazz.com>
Signed-off-by: Necip Fazil Yildiran <fazilyildiran@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The LLVM make variable allows a developer to quickly switch between the
GNU and LLVM tools. However, it does not handle versioned binaries, such
as the ones shipped by Debian, as LLVM=1 just defines the tool variables
with the unversioned binaries.
There was some discussion during the review of the patch that introduces
LLVM=1 around versioned binaries, ultimately coming to the conclusion
that developers can just add the folder that contains the unversioned
binaries to their PATH, as Debian's versioned suffixed binaries are
really just symlinks to the unversioned binaries in /usr/lib/llvm-#/bin:
$ realpath /usr/bin/clang-14
/usr/lib/llvm-14/bin/clang
$ PATH=/usr/lib/llvm-14/bin:$PATH make ... LLVM=1
However, that can be cumbersome to developers who are constantly testing
series with different toolchains and versions. It is simple enough to
support these versioned binaries directly in the Kbuild system by
allowing the developer to specify the version suffix with LLVM=, which
is shorter than the above suggestion:
$ make ... LLVM=-14
It does not change the meaning of LLVM=1 (which will continue to use
unversioned binaries) and it does not add too much additional complexity
to the existing $(LLVM) code, while allowing developers to quickly test
their series with different versions of the whole LLVM suite of tools.
Some developers may build LLVM from source but not add the binaries to
their PATH, as they may not want to use that toolchain systemwide.
Support those developers by allowing them to supply the directory that
the LLVM tools are available in, as it is no more complex to support
than the version suffix change above.
$ make ... LLVM=/path/to/llvm/
Update and reorder the documentation to reflect these new additions.
At the same time, notate that LLVM=0 is not the same as just omitting it
altogether, which has confused people in the past.
Link: https://lore.kernel.org/r/20200317215515.226917-1-ndesaulniers@google.com/
Link: https://lore.kernel.org/r/20220224151322.072632223@infradead.org/
Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
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>
`BAZ` takes `FOO`'s value as default (as far as `BAR` allows it).
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
- Remove the global -isystem compiler flag, which was made possible by
the introduction of <linux/stdarg.h>
- Improve the Kconfig help to print the location in the top menu level
- Fix "FORCE prerequisite is missing" build warning for sparc
- Add new build targets, tarzst-pkg and perf-tarzst-src-pkg, which generate
a zstd-compressed tarball
- Prevent gen_init_cpio tool from generating a corrupted cpio when
KBUILD_BUILD_TIMESTAMP is set to 2106-02-07 or later
- Misc cleanups
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Merge tag 'kbuild-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- Remove the global -isystem compiler flag, which was made possible by
the introduction of <linux/stdarg.h>
- Improve the Kconfig help to print the location in the top menu level
- Fix "FORCE prerequisite is missing" build warning for sparc
- Add new build targets, tarzst-pkg and perf-tarzst-src-pkg, which
generate a zstd-compressed tarball
- Prevent gen_init_cpio tool from generating a corrupted cpio when
KBUILD_BUILD_TIMESTAMP is set to 2106-02-07 or later
- Misc cleanups
* tag 'kbuild-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (28 commits)
kbuild: use more subdir- for visiting subdirectories while cleaning
sh: remove meaningless archclean line
initramfs: Check timestamp to prevent broken cpio archive
kbuild: split DEBUG_CFLAGS out to scripts/Makefile.debug
gen_init_cpio: add static const qualifiers
kbuild: Add make tarzst-pkg build option
scripts: update the comments of kallsyms support
sparc: Add missing "FORCE" target when using if_changed
kconfig: refactor conf_touch_dep()
kconfig: refactor conf_write_dep()
kconfig: refactor conf_write_autoconf()
kconfig: add conf_get_autoheader_name()
kconfig: move sym_escape_string_value() to confdata.c
kconfig: refactor listnewconfig code
kconfig: refactor conf_write_symbol()
kconfig: refactor conf_write_heading()
kconfig: remove 'const' from the return type of sym_escape_string_value()
kconfig: rename a variable in the lexer to a clearer name
kconfig: narrow the scope of variables in the lexer
kconfig: Create links to main menu items in search
...
- Some small scripts/kerneldoc fixes
- More Chinese translation work, but at a much reduced rate.
- The tip-tree maintainer's handbook
...plus the usual array of build fixes, typo fixes, etc.
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Merge tag 'docs-5.16' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"This is a relatively unexciting cycle for documentation.
- Some small scripts/kerneldoc fixes
- More Chinese translation work, but at a much reduced rate.
- The tip-tree maintainer's handbook
...plus the usual array of build fixes, typo fixes, etc"
* tag 'docs-5.16' of git://git.lwn.net/linux: (53 commits)
kernel-doc: support DECLARE_PHY_INTERFACE_MASK()
docs/zh_CN: add core-api xarray translation
docs/zh_CN: add core-api assoc_array translation
speakup: Fix typo in documentation "boo" -> "boot"
docs: submitting-patches: make section about the Link: tag more explicit
docs: deprecated.rst: Clarify open-coded arithmetic with literals
scripts: documentation-file-ref-check: fix bpf selftests path
scripts: documentation-file-ref-check: ignore hidden files
coding-style.rst: trivial: fix location of driver model macros
docs: f2fs: fix text alignment
docs/zh_CN add PCI pci.rst translation
docs/zh_CN add PCI index.rst translation
docs: translations: zh_CN: memory-hotplug.rst: fix a typo
docs: translations: zn_CN: irq-affinity.rst: add a missing extension
block: add documentation for inflight
scripts: kernel-doc: Ignore __alloc_size() attribute
docs: pdfdocs: Adjust \headheight for fancyhdr
docs: UML: user_mode_linux_howto_v2 edits
docs: use the lore redirector everywhere
docs: proc.rst: mountinfo: align columns
...
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)
This plugin has no impact on the resulting binary, is disabled
under COMPILE_TEST, and is not enabled on any builds I'm aware of.
Additionally, given the clarified purpose of GCC plugins in the kernel,
remove cyc_complexity.
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-hardening@vger.kernel.org
Cc: linux-kbuild@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20211020173554.38122-3-keescook@chromium.org
GCC plugins should only exist when some compiler feature needs to be
proven but does not exist in either GCC nor Clang. For example, if a
desired feature is already in Clang, it should be added to GCC upstream.
Document this explicitly.
Additionally, mark the plugins with matching upstream GCC features as
removable past their respective GCC versions.
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: linux-hardening@vger.kernel.org
Cc: linux-kbuild@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: llvm@lists.linux.dev
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20211020173554.38122-2-keescook@chromium.org
Change all links from using the lkml redirector to the lore redirector,
as the kernel.org admin recently indicated: we shouldn't be using
lkml.kernel.org anymore because the domain can create confusion, as it
indicates it is only valid for messages sent to the LKML; the convention
has been to use https://lore.kernel.org/r/msgid for this reason.
In this process also change three links from using http to https.
Link: https://lore.kernel.org/r/20211006170025.qw3glxvocczfuhar@meerkat.local
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Ingo Molnar <mingo@redhat.com>
CC: Borislav Petkov <bp@alien8.de>
CC: Hu Haowen <src.res@email.cn>
CC: Alex Shi <alexs@kernel.org>
CC: Federico Vaga <federico.vaga@vaga.pv.it>
Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info>
Reviewed-by: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
Link: https://lore.kernel.org/r/5bb55bac6ba10fafab19bf2b21572dd0e2f8cea2.1633593385.git.linux@leemhuis.info
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Merge more updates from Andrew Morton:
"147 patches, based on 7d2a07b769.
Subsystems affected by this patch series: mm (memory-hotplug, rmap,
ioremap, highmem, cleanups, secretmem, kfence, damon, and vmscan),
alpha, percpu, procfs, misc, core-kernel, MAINTAINERS, lib,
checkpatch, epoll, init, nilfs2, coredump, fork, pids, criu, kconfig,
selftests, ipc, and scripts"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (94 commits)
scripts: check_extable: fix typo in user error message
mm/workingset: correct kernel-doc notations
ipc: replace costly bailout check in sysvipc_find_ipc()
selftests/memfd: remove unused variable
Kconfig.debug: drop selecting non-existing HARDLOCKUP_DETECTOR_ARCH
configs: remove the obsolete CONFIG_INPUT_POLLDEV
prctl: allow to setup brk for et_dyn executables
pid: cleanup the stale comment mentioning pidmap_init().
kernel/fork.c: unexport get_{mm,task}_exe_file
coredump: fix memleak in dump_vma_snapshot()
fs/coredump.c: log if a core dump is aborted due to changed file permissions
nilfs2: use refcount_dec_and_lock() to fix potential UAF
nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group
nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group
nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group
nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group
nilfs2: fix NULL pointer in nilfs_##name##_attr_release
nilfs2: fix memory leak in nilfs_sysfs_create_device_group
trap: cleanup trap_init()
init: move usermodehelper_enable() to populate_rootfs()
...
This should have been done with commit 91ed3ed0f7 ("MAINTAINERS: update
ClangBuiltLinux IRC chat") but I did not realize it was in two separate
spots.
Link: https://lkml.kernel.org/r/20210825211823.6406-3-nathan@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We are now at llvm@lists.linux.dev.
Link: https://lkml.kernel.org/r/20210825211823.6406-2-nathan@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
LLVM_IAS=1 controls enabling clang's integrated assembler via
-integrated-as. This was an explicit opt in until we could enable
assembler support in Clang for more architecures. Now we have support
and CI coverage of LLVM_IAS=1 for all architecures except a few more
bugs affecting s390 and powerpc.
This commit flips the default from opt in via LLVM_IAS=1 to opt out via
LLVM_IAS=0. CI systems or developers that were previously doing builds
with CC=clang or LLVM=1 without explicitly setting LLVM_IAS must now
explicitly opt out via LLVM_IAS=0, otherwise they will be implicitly
opted-in.
This finally shortens the command line invocation when cross compiling
with LLVM to simply:
$ make ARCH=arm64 LLVM=1
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
As noted by Masahiro, document how we can generally infer CROSS_COMPILE
(and the more specific details about --target and --prefix) based on
ARCH.
Change use of env vars to command line parameters.
Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Fangrui Song <maskray@google.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
- Change 'option defconfig' to the environment variable
KCONFIG_DEFCONFIG_LIST
- Refactor tinyconfig without using allnoconfig_y
- Remove 'option allnoconfig_y' syntax
- Change 'option modules' to 'modules'
- Do not use /boot/config-* etc. as base config for cross-compilation
- Fix a search bug in nconf
- Various code cleanups
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Merge tag 'kconfig-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kconfig updates from Masahiro Yamada:
- Change 'option defconfig' to the environment variable
KCONFIG_DEFCONFIG_LIST
- Refactor tinyconfig without using allnoconfig_y
- Remove 'option allnoconfig_y' syntax
- Change 'option modules' to 'modules'
- Do not use /boot/config-* etc. as base config for cross-compilation
- Fix a search bug in nconf
- Various code cleanups
* tag 'kconfig-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits)
kconfig: refactor .gitignore
kconfig: highlight xconfig 'comment' lines with '***'
kconfig: highlight gconfig 'comment' lines with '***'
kconfig: gconf: remove unused code
kconfig: remove unused PACKAGE definition
kconfig: nconf: stop endless search loops
kconfig: split menu.c out of parser.y
kconfig: nconf: refactor in print_in_middle()
kconfig: nconf: remove meaningless wattrset() call from show_menu()
kconfig: nconf: change set_config_filename() to void function
kconfig: nconf: refactor attributes setup code
kconfig: nconf: remove unneeded default for menu prompt
kconfig: nconf: get rid of (void) casts from wattrset() calls
kconfig: nconf: fix NORMAL attributes
kconfig: mconf,nconf: remove unneeded '\0' termination after snprintf()
kconfig: use /boot/config-* etc. as DEFCONFIG_LIST only for native build
kconfig: change sym_change_count to a boolean flag
kconfig: nconf: fix core dump when searching in empty menu
kconfig: lxdialog: A spello fix and a punctuation added
kconfig: streamline_config.pl: Couple of typo fixes
...
Now "modules" is the only member of the "option" property.
Remove "option", and move "modules" to the top level property.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
"defconfig_list" is a weird option that defines a static symbol that
declares the list of base config files in case the .config does not
exist yet.
This is quite different from other normal symbols; we just abused the
"string" type and the "default" properties to list out the input files.
They must be fixed values since these are searched for and loaded in
the parse stage.
It is an ugly hack, and should not exist in the first place. Providing
this feature as an environment variable is a saner approach.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
- 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 most common question around building the Linux kernel with clang is
"does it work?" and the answer has always been "it depends on your
architecture, configuration, and LLVM version" with no hard answers for
users wanting to experiment. LLVM support has significantly improved
over the past couple of years, resulting in more architectures and
configurations supported, and continuous integration has made it easier
to see what works and what does not.
Add a section that goes over what architectures are supported in the
current kernel version, how they should be built (with just clang or the
LLVM utilities as well), and the level of support they receive. This
will make it easier for people to try out building their kernel with
LLVM and reporting issues that come about from it.
Suggested-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulnier@google.com>
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>
This document was written a long time ago. Update it.
[1] Drop the version information
The range of the supported GCC versions are always changing. The
current minimal GCC version is 4.9, and commit 1e860048c5
("gcc-plugins: simplify GCC plugin-dev capability test") removed the
old code accordingly.
We do not need to mention specific version ranges like "all gcc versions
from 4.5 to 6.0" since we forget to update the documentation when we
raise the minimal compiler version.
[2] Drop the C compiler statements
Since commit 77342a02ff ("gcc-plugins: drop support for GCC <= 4.7")
the GCC plugin infrastructure only supports g++.
[3] Drop supported architectures
As of v5.11-rc4, the infrastructure supports more architectures;
arm, arm64, mips, powerpc, riscv, s390, um, and x86. (just grep
"select HAVE_GCC_PLUGINS") Again, we miss to update this document when a
new architecture is supported. Let's just say "only some architectures".
[4] Update the apt-get example
We are now discussing to bump the minimal version to GCC 5. The GCC 4.9
support will be removed sooner or later. Change the package example to
gcc-10-plugin-dev while we are here.
[5] Update the build target
Since commit ce2fd53a10 ("kbuild: descend into scripts/gcc-plugins/
via scripts/Makefile"), "make gcc-plugins" is not supported.
"make scripts" builds all the enabled plugins, including some other
tools.
[6] Update the steps for adding a new plugin
At first, all CONFIG options for GCC plugins were located in arch/Kconfig.
After commit 45332b1bdf ("gcc-plugins: split out Kconfig entries to
scripts/gcc-plugins/Kconfig"), scripts/gcc-plugins/Kconfig became the
central place to collect plugin CONFIG options. In my understanding,
this requirement no longer exists because commit 9f671e5815 ("security:
Create "kernel hardening" config area") moved some of plugin CONFIG
options to another file. Find an appropriate place to add the new CONFIG.
The sub-directory support was never used by anyone, and removed by
commit c17d6179ad ("gcc-plugins: remove unused GCC_PLUGIN_SUBDIR").
Remove the useless $(src)/ prefix.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
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>
- Support only Qt5 for qconf
- Validate signal/slot connection at compile time of qconf
- Sanitize header includes
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Merge tag 'kconfig-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kconfig updates from Masahiro Yamada:
- Support only Qt5 for qconf
- Validate signal/slot connection at compile time of qconf
- Sanitize header includes
* tag 'kconfig-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kconfig: doc: fix $(fileno) to $(filename)
kconfig: fix return value of do_error_if()
kconfig: clean up header inclusion
kconfig: qconf: show Qt version in the About dialog
kconfig: make lkc.h self-sufficient #include-wise
kconfig: qconf: convert to Qt5 new signal/slot connection syntax
kconfig: qconf: use a variable to pass packages to pkg-config
kconfig: qconf: drop Qt4 support
Document best practises for using architecture and platform dependencies.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
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>
The "size" tool has been solely used by s390 to enforce .bss section usage
restrictions in early startup code. Since commit 980d5f9ab3 ("s390/boot:
enable .bss section for compressed kernel") and commit 2e83e0eb85
("s390: clean .bss before running uncompressed kernel") these restrictions
have been lifted for the decompressor and uncompressed kernel and the
size tool is now unused.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
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>
no conflicts at all. This pull includes:
- A reworked and expanded user-mode Linux document
- Some simplifications and improvements for submitting-patches.rst
- An emergency fix for (some) problems with Sphinx 3.x
- Some welcome automarkup improvements to automatically generate
cross-references to struct definitions and other documents
- The usual collection of translation updates, typo fixes, etc.
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Merge tag 'docs-5.10' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"As hoped, things calmed down for docs this cycle; fewer changes and
almost no conflicts at all. This includes:
- A reworked and expanded user-mode Linux document
- Some simplifications and improvements for submitting-patches.rst
- An emergency fix for (some) problems with Sphinx 3.x
- Some welcome automarkup improvements to automatically generate
cross-references to struct definitions and other documents
- The usual collection of translation updates, typo fixes, etc"
* tag 'docs-5.10' of git://git.lwn.net/linux: (81 commits)
gpiolib: Update indentation in driver.rst for code excerpts
Documentation/admin-guide: tainted-kernels: Fix typo occured
Documentation: better locations for sysfs-pci, sysfs-tagging
docs: programming-languages: refresh blurb on clang support
Documentation: kvm: fix a typo
Documentation: Chinese translation of Documentation/arm64/amu.rst
doc: zh_CN: index files in arm64 subdirectory
mailmap: add entry for <mstarovoitov@marvell.com>
doc: seq_file: clarify role of *pos in ->next()
docs: trace: ring-buffer-design.rst: use the new SPDX tag
Documentation: kernel-parameters: clarify "module." parameters
Fix references to nommu-mmap.rst
docs: rewrite admin-guide/sysctl/abi.rst
docs: fb: Remove vesafb scrollback boot option
docs: fb: Remove sstfb scrollback boot option
docs: fb: Remove matroxfb scrollback boot option
docs: fb: Remove framebuffer scrollback boot option
docs: replace the old User Mode Linux HowTo with a new one
Documentation/admin-guide: blockdev/ramdisk: remove use of "rdev"
Documentation/admin-guide: README & svga: remove use of "rdev"
...