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 13+ 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>
Bug: 214127735
Link: https://lore.kernel.org/linux-kbuild/20220201213542.2808035-1-quic_eberman@quicinc.com/
Change-Id: I035309a569130774a1212f294973eee2830a6588
(cherry picked from commit df704104322c6bd1b3d40cb7ad109cba7453f3be)
Changes in 5.10.85
usb: gadget: uvc: fix multiple opens
gcc-plugins: simplify GCC plugin-dev capability test
gcc-plugins: fix gcc 11 indigestion with plugins...
HID: quirks: Add quirk for the Microsoft Surface 3 type-cover
HID: google: add eel USB id
HID: add hid_is_usb() function to make it simpler for USB detection
HID: add USB_HID dependancy to hid-prodikeys
HID: add USB_HID dependancy to hid-chicony
HID: add USB_HID dependancy on some USB HID drivers
HID: bigbenff: prevent null pointer dereference
HID: wacom: fix problems when device is not a valid USB device
HID: check for valid USB device for many HID drivers
nft_set_pipapo: Fix bucket load in AVX2 lookup routine for six 8-bit groups
IB/hfi1: Insure use of smp_processor_id() is preempt disabled
IB/hfi1: Fix early init panic
IB/hfi1: Fix leak of rcvhdrtail_dummy_kvaddr
can: kvaser_usb: get CAN clock frequency from device
can: kvaser_pciefd: kvaser_pciefd_rx_error_frame(): increase correct stats->{rx,tx}_errors counter
can: sja1000: fix use after free in ems_pcmcia_add_card()
x86/sme: Explicitly map new EFI memmap table as encrypted
drm/amd/amdkfd: adjust dummy functions' placement
drm/amdkfd: separate kfd_iommu_resume from kfd_resume
drm/amdgpu: add amdgpu_amdkfd_resume_iommu
drm/amdgpu: move iommu_resume before ip init/resume
drm/amdgpu: init iommu after amdkfd device init
drm/amdkfd: fix boot failure when iommu is disabled in Picasso.
nfc: fix potential NULL pointer deref in nfc_genl_dump_ses_done
selftests: netfilter: add a vrf+conntrack testcase
vrf: don't run conntrack on vrf with !dflt qdisc
bpf, x86: Fix "no previous prototype" warning
bpf: Fix the off-by-two error in range markings
ice: ignore dropped packets during init
bonding: make tx_rebalance_counter an atomic
nfp: Fix memory leak in nfp_cpp_area_cache_add()
seg6: fix the iif in the IPv6 socket control block
udp: using datalen to cap max gso segments
netfilter: conntrack: annotate data-races around ct->timeout
iavf: restore MSI state on reset
iavf: Fix reporting when setting descriptor count
IB/hfi1: Correct guard on eager buffer deallocation
devlink: fix netns refcount leak in devlink_nl_cmd_reload()
net/sched: fq_pie: prevent dismantle issue
KVM: x86: Wait for IPIs to be delivered when handling Hyper-V TLB flush hypercall
mm: bdi: initialize bdi_min_ratio when bdi is unregistered
ALSA: ctl: Fix copy of updated id with element read/write
ALSA: hda/realtek - Add headset Mic support for Lenovo ALC897 platform
ALSA: hda/realtek: Fix quirk for TongFang PHxTxX1
ALSA: pcm: oss: Fix negative period/buffer sizes
ALSA: pcm: oss: Limit the period size to 16MB
ALSA: pcm: oss: Handle missing errors in snd_pcm_oss_change_params*()
scsi: qla2xxx: Format log strings only if needed
btrfs: clear extent buffer uptodate when we fail to write it
btrfs: replace the BUG_ON in btrfs_del_root_ref with proper error handling
md: fix update super 1.0 on rdev size change
nfsd: fix use-after-free due to delegation race
nfsd: Fix nsfd startup race (again)
tracefs: Have new files inherit the ownership of their parent
mmc: renesas_sdhi: initialize variable properly when tuning
clk: qcom: regmap-mux: fix parent clock lookup
drm/syncobj: Deal with signalled fences in drm_syncobj_find_fence.
can: pch_can: pch_can_rx_normal: fix use after free
can: m_can: Disable and ignore ELO interrupt
libata: add horkage for ASMedia 1092
wait: add wake_up_pollfree()
binder: use wake_up_pollfree()
signalfd: use wake_up_pollfree()
aio: keep poll requests on waitqueue until completed
aio: fix use-after-free due to missing POLLFREE handling
net: mvpp2: fix XDP rx queues registering
tracefs: Set all files to the same group ownership as the mount option
block: fix ioprio_get(IOPRIO_WHO_PGRP) vs setuid(2)
scsi: pm80xx: Do not call scsi_remove_host() in pm8001_alloc()
scsi: scsi_debug: Fix buffer size of REPORT ZONES command
qede: validate non LSO skb length
PM: runtime: Fix pm_runtime_active() kerneldoc comment
ASoC: rt5682: Fix crash due to out of scope stack vars
ASoC: qdsp6: q6routing: Fix return value from msm_routing_put_audio_mixer
ASoC: codecs: wsa881x: fix return values from kcontrol put
ASoC: codecs: wcd934x: handle channel mappping list correctly
ASoC: codecs: wcd934x: return correct value from mixer put
RDMA/hns: Do not halt commands during reset until later
RDMA/hns: Do not destroy QP resources in the hw resetting phase
clk: imx: use module_platform_driver
i40e: Fix failed opcode appearing if handling messages from VF
i40e: Fix pre-set max number of queues for VF
mtd: rawnand: fsmc: Take instruction delay into account
mtd: rawnand: fsmc: Fix timing computation
i40e: Fix NULL pointer dereference in i40e_dbg_dump_desc
Revert "PCI: aardvark: Fix support for PCI_ROM_ADDRESS1 on emulated bridge"
perf tools: Fix SMT detection fast read path
Documentation/locking/locktypes: Update migrate_disable() bits.
dt-bindings: net: Reintroduce PHY no lane swap binding
tools build: Remove needless libpython-version feature check that breaks test-all fast path
net: cdc_ncm: Allow for dwNtbOutMaxSize to be unset or zero
net: altera: set a couple error code in probe()
net: fec: only clear interrupt of handling queue in fec_enet_rx_queue()
net, neigh: clear whole pneigh_entry at alloc time
net/qla3xxx: fix an error code in ql_adapter_up()
selftests/fib_tests: Rework fib_rp_filter_test()
USB: gadget: detect too-big endpoint 0 requests
USB: gadget: zero allocate endpoint 0 buffers
usb: core: config: fix validation of wMaxPacketValue entries
xhci: Remove CONFIG_USB_DEFAULT_PERSIST to prevent xHCI from runtime suspending
usb: core: config: using bit mask instead of individual bits
xhci: avoid race between disable slot command and host runtime suspend
iio: gyro: adxrs290: fix data signedness
iio: trigger: Fix reference counting
iio: trigger: stm32-timer: fix MODULE_ALIAS
iio: stk3310: Don't return error code in interrupt handler
iio: mma8452: Fix trigger reference couting
iio: ltr501: Don't return error code in trigger handler
iio: kxsd9: Don't return error code in trigger handler
iio: itg3200: Call iio_trigger_notify_done() on error
iio: dln2-adc: Fix lockdep complaint
iio: dln2: Check return value of devm_iio_trigger_register()
iio: at91-sama5d2: Fix incorrect sign extension
iio: adc: stm32: fix a current leak by resetting pcsel before disabling vdda
iio: adc: axp20x_adc: fix charging current reporting on AXP22x
iio: ad7768-1: Call iio_trigger_notify_done() on error
iio: accel: kxcjk-1013: Fix possible memory leak in probe and remove
csky: fix typo of fpu config macro
irqchip/aspeed-scu: Replace update_bits with write_bits.
irqchip/armada-370-xp: Fix return value of armada_370_xp_msi_alloc()
irqchip/armada-370-xp: Fix support for Multi-MSI interrupts
irqchip/irq-gic-v3-its.c: Force synchronisation when issuing INVALL
irqchip: nvic: Fix offset for Interrupt Priority Offsets
misc: fastrpc: fix improper packet size calculation
bpf: Add selftests to cover packet access corner cases
kbuild: simplify GCC_PLUGINS enablement in dummy-tools/gcc
doc: gcc-plugins: update gcc-plugins.rst
MAINTAINERS: adjust GCC PLUGINS after gcc-plugin.sh removal
Documentation/Kbuild: Remove references to gcc-plugin.sh
Linux 5.10.85
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I351da1b00f30a370b021125180a48b1c1ecb97ce
commit 9b6164342e upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.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>
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"
...
clang --target=<triple> is how we can specify a particular toolchain
triple to be use, fix the two occurences in the documentation.
Fixes: fcf1b6a35c ("Documentation/llvm: add documentation on building w/ Clang/LLVM")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.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>
Based on a vote at the LLVM BoF at Plumbers 2020, we decided to start
small, supporting just one formal upstream release of LLVM for now.
We can probably widen the support window of supported versions over
time. Also, note that LLVM's release process is different than GCC's.
GCC tends to have 1 major release per year while releasing minor updates
to the past 3 major versions. LLVM tends to support one major release
and one minor release every six months.
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200826191555.3350406-1-ndesaulniers@google.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
While reviewing a separate patch, I noticed that the formatting of the
commands, variables, and arguments was not in a monospaced font like the
rest of the Kbuild documentation (see kbuild/kconfig.rst for an
example). This is due to a lack of "::" before indented command blocks
and single backticks instead of double backticks for inline formatting.
Add those so that the document looks nicer in an HTML format, while not
ruining the look in plain text.
As a result of this, we can remove the escaped backslashes in the last
code block and move them to single backslashes.
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull Kbuild updates from Masahiro Yamada:
- run the checker (e.g. sparse) after the compiler
- remove unneeded cc-option tests for old compiler flags
- fix tar-pkg to install dtbs
- introduce ccflags-remove-y and asflags-remove-y syntax
- allow to trace functions in sub-directories of lib/
- introduce hostprogs-always-y and userprogs-always-y syntax
- various Makefile cleanups
* tag 'kbuild-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: stop filtering out $(GCC_PLUGINS_CFLAGS) from cc-option base
kbuild: include scripts/Makefile.* only when relevant CONFIG is enabled
kbuild: introduce hostprogs-always-y and userprogs-always-y
kbuild: sort hostprogs before passing it to ifneq
kbuild: move host .so build rules to scripts/gcc-plugins/Makefile
kbuild: Replace HTTP links with HTTPS ones
kbuild: trace functions in subdirectories of lib/
kbuild: introduce ccflags-remove-y and asflags-remove-y
kbuild: do not export LDFLAGS_vmlinux
kbuild: always create directories of targets
powerpc/boot: add DTB to 'targets'
kbuild: buildtar: add dtbs support
kbuild: remove cc-option test of -ffreestanding
kbuild: remove cc-option test of -fno-stack-protector
Revert "kbuild: Create directory for target DTB"
kbuild: run the checker after the compiler
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>
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
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>
Steps on the way to 5.9-rc1
Resolves conflicts in:
drivers/irqchip/qcom-pdc.c
include/linux/device.h
net/xfrm/xfrm_state.c
security/lsm_audit.c
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I4aeb3d04f4717714a421721eb3ce690c099bb30a
Pull documentation updates from Jonathan Corbet:
"It's been a busy cycle for documentation - hopefully the busiest for a
while to come. Changes include:
- Some new Chinese translations
- Progress on the battle against double words words and non-HTTPS
URLs
- Some block-mq documentation
- More RST conversions from Mauro. At this point, that task is
essentially complete, so we shouldn't see this kind of churn again
for a while. Unless we decide to switch to asciidoc or
something...:)
- Lots of typo fixes, warning fixes, and more"
* tag 'docs-5.9' of git://git.lwn.net/linux: (195 commits)
scripts/kernel-doc: optionally treat warnings as errors
docs: ia64: correct typo
mailmap: add entry for <alobakin@marvell.com>
doc/zh_CN: add cpu-load Chinese version
Documentation/admin-guide: tainted-kernels: fix spelling mistake
MAINTAINERS: adjust kprobes.rst entry to new location
devices.txt: document rfkill allocation
PCI: correct flag name
docs: filesystems: vfs: correct flag name
docs: filesystems: vfs: correct sync_mode flag names
docs: path-lookup: markup fixes for emphasis
docs: path-lookup: more markup fixes
docs: path-lookup: fix HTML entity mojibake
CREDITS: Replace HTTP links with HTTPS ones
docs: process: Add an example for creating a fixes tag
doc/zh_CN: add Chinese translation prefer section
doc/zh_CN: add clearing-warn-once Chinese version
doc/zh_CN: add admin-guide index
doc:it_IT: process: coding-style.rst: Correct __maybe_unused compiler label
futex: MAINTAINERS: Re-add selftests directory
...
Add support for installing out-of-tree kernel headers. The
"headers_install" target was copied to the external module compilation
section (lines 1245:1270), and the src/obj variables were tweaked to
include $(KBUILD_EXTMODULE).
Bug: 162332589
Change-Id: I2e2c7598612bea94267e6a9bc6d0793da53915ac
Signed-off-by: Elliot Berman <eberman@codeaurora.org>
Some Makefiles already pass -fno-stack-protector unconditionally.
For example, arch/arm64/kernel/vdso/Makefile, arch/x86/xen/Makefile.
No problem report so far about hard-coding this option. So, we can
assume all supported compilers know -fno-stack-protector.
GCC 4.8 and Clang support this option (https://godbolt.org/z/_HDGzN)
Get rid of cc-option from -fno-stack-protector.
Remove CONFIG_CC_HAS_STACKPROTECTOR_NONE, which is always 'y'.
Note:
arch/mips/vdso/Makefile adds -fno-stack-protector twice, first
unconditionally, and second conditionally. I removed the second one.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Commit cd238effef ("docs: kbuild: convert docs to ReST and rename to
*.rst") missed a ReST header and a verbatim file content area.
Signed-off-by: Dov Murik <dovmurik@linux.vnet.ibm.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This is a left-over of commit 39808e451f ("kbuild: do not read
$(KBUILD_EXTMOD)/Module.symvers").
Kbuild no longer supports this way.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.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>
As Documentation/kbuild/llvm.rst implies, building the kernel with a
full set of LLVM tools gets very verbose and unwieldy.
Provide a single switch LLVM=1 to use Clang and LLVM tools instead
of GCC and Binutils. You can pass it from the command line or as an
environment variable.
Please note LLVM=1 does not turn on the integrated assembler. You need
to pass LLVM_IAS=1 to use it. When the upstream kernel is ready for the
integrated assembler, I think we can make it default.
We discussed what we need, and we agreed to go with a simple boolean
flag that switches both target and host tools:
https://lkml.org/lkml/2020/3/28/494https://lkml.org/lkml/2020/4/3/43
Some items discussed, but not adopted:
- LLVM_DIR
When multiple versions of LLVM are installed, I just thought supporting
LLVM_DIR=/path/to/my/llvm/bin/ might be useful.
CC = $(LLVM_DIR)clang
LD = $(LLVM_DIR)ld.lld
...
However, we can handle this by modifying PATH. So, we decided to not do
this.
- LLVM_SUFFIX
Some distributions (e.g. Debian) package specific versions of LLVM with
naming conventions that use the version as a suffix.
CC = clang$(LLVM_SUFFIX)
LD = ld.lld(LLVM_SUFFIX)
...
will allow a user to pass LLVM_SUFFIX=-11 to use clang-11 etc.,
but the suffixed versions in /usr/bin/ are symlinks to binaries in
/usr/lib/llvm-#/bin/, so this can also be handled by PATH.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com> # build
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
The 'AS' variable is unused for building the kernel. Only the remaining
usage is to turn on the integrated assembler. A boolean flag is a better
fit for this purpose.
AS=clang was added for experts. So, I replaced it with LLVM_IAS=1,
breaking the backward compatibility.
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Pull Kbuild updates from Masahiro Yamada:
"Build system:
- add CONFIG_UNUSED_KSYMS_WHITELIST, which will be useful to define a
fixed set of export symbols for Generic Kernel Image (GKI)
- allow to run 'make dt_binding_check' without .config
- use full schema for checking DT examples in *.yaml files
- make modpost fail for missing MODULE_IMPORT_NS(), which makes more
sense because we know the produced modules are never loadable
- Remove unused 'AS' variable
Kconfig:
- sanitize DEFCONFIG_LIST, and remove ARCH_DEFCONFIG from Kconfig
files
- relax the 'imply' behavior so that symbols implied by 'y' can
become 'm'
- make 'imply' obey 'depends on' in order to make 'imply' really weak
Misc:
- add documentation on building the kernel with Clang/LLVM
- revive __HAVE_ARCH_STRLEN for 32bit sparc to use optimized strlen()
- fix warning from deb-pkg builds when CONFIG_DEBUG_INFO=n
- various script and Makefile cleanups"
* tag 'kbuild-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits)
Makefile: Update kselftest help information
kbuild: deb-pkg: fix warning when CONFIG_DEBUG_INFO is unset
kbuild: add outputmakefile to no-dot-config-targets
kbuild: remove AS variable
net: wan: wanxl: refactor the firmware rebuild rule
net: wan: wanxl: use $(M68KCC) instead of $(M68KAS) for rebuilding firmware
net: wan: wanxl: use allow to pass CROSS_COMPILE_M68k for rebuilding firmware
kbuild: add comment about grouped target
kbuild: add -Wall to KBUILD_HOSTCXXFLAGS
kconfig: remove unused variable in qconf.cc
sparc: revive __HAVE_ARCH_STRLEN for 32bit sparc
kbuild: refactor Makefile.dtbinst more
kbuild: compute the dtbs_install destination more simply
Makefile: disallow data races on gcc-10 as well
kconfig: make 'imply' obey the direct dependency
kconfig: allow symbols implied by y to become m
net: drop_monitor: use IS_REACHABLE() to guard net_dm_hw_report()
modpost: return error if module is missing ns imports and MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS=n
modpost: rework and consolidate logging interface
kbuild: allow to run dt_binding_check without kernel configuration
...
Pull documentation updates from Jonathan Corbet:
"This has been a busy cycle for documentation work.
Highlights include:
- Lots of RST conversion work by Mauro, Daniel ALmeida, and others.
Maybe someday we'll get to the end of this stuff...maybe...
- Some organizational work to bring some order to the core-api
manual.
- Various new docs and additions to the existing documentation.
- Typo fixes, warning fixes, ..."
* tag 'docs-5.7' of git://git.lwn.net/linux: (123 commits)
Documentation: x86: exception-tables: document CONFIG_BUILDTIME_TABLE_SORT
MAINTAINERS: adjust to filesystem doc ReST conversion
docs: deprecated.rst: Add BUG()-family
doc: zh_CN: add translation for virtiofs
doc: zh_CN: index files in filesystems subdirectory
docs: locking: Drop :c:func: throughout
docs: locking: Add 'need' to hardirq section
docs: conf.py: avoid thousands of duplicate label warning on Sphinx
docs: prevent warnings due to autosectionlabel
docs: fix reference to core-api/namespaces.rst
docs: fix pointers to io-mapping.rst and io_ordering.rst files
Documentation: Better document the softlockup_panic sysctl
docs: hw-vuln: tsx_async_abort.rst: get rid of an unused ref
docs: perf: imx-ddr.rst: get rid of a warning
docs: filesystems: fuse.rst: supress a Sphinx warning
docs: translations: it: avoid duplicate refs at programming-language.rst
docs: driver.rst: supress two ReSt warnings
docs: trace: events.rst: convert some new stuff to ReST format
Documentation: Add io_ordering.rst to driver-api manual
Documentation: Add io-mapping.rst to driver-api manual
...
In order to preserve backwards compatability with kmod tools, we have to
move the namespace field in Module.symvers last, as the depmod -e -E
option looks at the first three fields in Module.symvers to check symbol
versions (and it's expected they stay in the original order of crc,
symbol, module).
In addition, update an ancient comment above read_dump() in modpost that
suggested that the export type field in Module.symvers was optional. I
suspect that there were historical reasons behind that comment that are
no longer accurate. We have been unconditionally printing the export
type since 2.6.18 (commit bd5cbcedf4), which is over a decade ago now.
Fix up read_dump() to treat each field as non-optional. I suspect the
original read_dump() code treated the export field as optional in order
to support pre <= 2.6.18 Module.symvers (which did not have the export
type field). Note that although symbol namespaces are optional, the
field will not be omitted from Module.symvers if a symbol does not have
a namespace. In this case, the field will simply be empty and the next
delimiter or end of line will follow.
Cc: stable@vger.kernel.org
Fixes: cb9b55d21f ("modpost: add support for symbol namespaces")
Tested-by: Matthias Maennich <maennich@google.com>
Reviewed-by: Matthias Maennich <maennich@google.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The 'imply' statement may create unmet direct dependency when the
implied symbol depends on m.
[Test Code]
config FOO
tristate "foo"
imply BAZ
config BAZ
tristate "baz"
depends on BAR
config BAR
def_tristate m
config MODULES
def_bool y
option modules
If you set FOO=y, BAZ is also promoted to y, which results in the
following .config file:
CONFIG_FOO=y
CONFIG_BAZ=y
CONFIG_BAR=m
CONFIG_MODULES=y
This does not meet the dependency 'BAZ depends on BAR'.
Unlike 'select', what is worse, Kconfig never shows the
'WARNING: unmet direct dependencies detected for ...' for this case.
Because 'imply' is considered to be weaker than 'depends on', Kconfig
should take the direct dependency into account.
For clarification, describe this case in kconfig-language.rst too.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
The 'imply' keyword restricts a symbol to y or n, excluding m
when it is implied by y. This is the original behavior since
commit 237e3ad0f1 ("Kconfig: Introduce the "imply" keyword").
However, the author of this feature, Nicolas Pitre, stated that
the 'imply' keyword should not impose any restrictions.
(https://lkml.org/lkml/2020/2/19/714)
I agree, and want to get rid of this tricky behavior.
Suggested-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Information about GCC plugins is relevant to kernel building, so move this
document to the kbuild manual.
Acked-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
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>
Pull Kconfig updates from Masahiro Yamada:
- add 'yes2modconfig' and 'mod2yesconfig' targets (useful mainly for
turning syzbot configs into more modular ones as a step to minimizing
the result)
- sanitize help text
- various code cleanups
* tag 'kconfig-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kconfig: fix documentation typos
kconfig: fix an "implicit declaration of function" warning
kconfig: fix nesting of symbol help text
kconfig: distinguish between dependencies and visibility in help text
kconfig: list all definitions of a symbol in help text
kconfig: Add yes2modconfig and mod2yesconfig targets.
kconfig: use $(PERL) in Makefile
kconfig: fix too deep indentation in Makefile
kconfig: localmodconfig: fix indentation for closing brace
kconfig: localmodconfig: remove unused $config
kconfig: squash prop_alloc() into menu_add_prop()
kconfig: remove sym from struct property
kconfig: remove 'prompt' argument from menu_add_prop()
kconfig: move prompt handling to menu_add_prompt() from menu_add_prop()
kconfig: remove 'prompt' symbol
kconfig: drop T_WORD from the RHS of 'prompt' symbol
kconfig: use parent->dep as the parentdep of 'menu'
kconfig: remove the rootmenu check in menu_add_prop()
Commit bc081dd6e9 ("kbuild: generate modules.builtin") added
infrastructure to generate modules.builtin, the list of all
builtin modules.
Basically, it works like this:
- Kconfig generates include/config/tristate.conf, the list of
tristate CONFIG options with a value in a capital letter.
- scripts/Makefile.modbuiltin makes Kbuild descend into
directories to collect the information of builtin modules.
I am not a big fan of it because Kbuild ends up with traversing
the source tree twice.
I am not sure how perfectly it should work, but this approach cannot
avoid false positives; even if the relevant CONFIG option is tristate,
some Makefiles forces obj-m to obj-y.
Some examples are:
arch/powerpc/platforms/powermac/Makefile:
obj-$(CONFIG_NVRAM:m=y) += nvram.o
net/ipv6/Makefile:
obj-$(subst m,y,$(CONFIG_IPV6)) += inet6_hashtables.o
net/netlabel/Makefile:
obj-$(subst m,y,$(CONFIG_IPV6)) += netlabel_calipso.o
Nobody has complained about (or noticed) it, so it is probably fine to
have false positives in modules.builtin.
This commit simplifies the implementation. Let's exploit the fact
that every module has MODULE_LICENSE(). (modpost shows a warning if
MODULE_LICENSE is missing. If so, 0-day bot would already have blocked
such a module.)
I added MODULE_FILE to <linux/module.h>. When the code is being compiled
as builtin, it will be filled with the file path of the module, and
collected into modules.builtin.info. Then, scripts/link-vmlinux.sh
extracts the list of builtin modules out of it.
This new approach fixes the false-positives above, but adds another
type of false-positives; non-modular code may have MODULE_LICENSE()
by mistake. This is not a big deal, it is just the code is always
orphan. We can clean it up if we like. You can see cleanup examples by:
$ git log --grep='make.* explicitly non-modular'
To sum up, this commits deletes lots of code, but still produces almost
equivalent results. Please note it does not increase the vmlinux size at
all. As you can see in include/asm-generic/vmlinux.lds.h, the .modinfo
section is discarded in the link stage.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Elliot Berman