Commit 5318321d36 ("samples: disable CONFIG_SAMPLES for UML") used
a big hammer to fix the build errors under the samples/ directory.
Only some samples actually include uapi headers from usr/include.
Introduce CONFIG_HEADERS_INSTALL since 'depends on HEADERS_INSTALL' is
clearer than 'depends on !UML'. If this option is enabled, uapi headers
are installed before starting directory descending.
I added 'depends on HEADERS_INSTALL' to per-sample CONFIG options.
This allows UML to compile some samples.
$ make ARCH=um allmodconfig samples/
[ snip ]
CC [M] samples/configfs/configfs_sample.o
CC [M] samples/kfifo/bytestream-example.o
CC [M] samples/kfifo/dma-example.o
CC [M] samples/kfifo/inttype-example.o
CC [M] samples/kfifo/record-example.o
CC [M] samples/kobject/kobject-example.o
CC [M] samples/kobject/kset-example.o
CC [M] samples/trace_events/trace-events-sample.o
CC [M] samples/trace_printk/trace-printk.o
AR samples/vfio-mdev/built-in.a
AR samples/built-in.a
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
'gdb_script' needs headers generated by ./Kbuild, which is visited
by 'prepare0'. None of 'gdb_script' depends on 'prepare'.
Loosen the dependency.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Commit 8e2faea877 ("Make Documenation depend on headers_install")
dates back to 2014, which is before Sphinx was introduced for the
kernel documentation.
Since none of DOC_TARGET requires headers_install, it is strange to
run it only for the single target "Documentation/".
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
headers_install_all does not make much sense any more because different
architectures export different set of uapi/linux/ headers. As you see
in include/uapi/linux/Kbuild, the installation of a.out.h, kvm.h, and
kvm_para.h is arch-dependent. So, headers_install_all repeats the
installation/removal of them.
If somebody really thinks it is useful to do headers_install for all
architectures, it would be possible by small shell-scripting, but
the top Makefile does not have to provide entry targets just for that
purpose.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Current implementation of kselftest-merge only finds config files that
are one level deep using `$(srctree)/tools/testing/selftests/*/config`.
Often, config files are added in nested directories, and do not get
picked up by kselftest-merge.
Use `find` to catch all config files under
`$(srctree)/tools/testing/selftests` instead.
Signed-off-by: Dan Rue <dan.rue@linaro.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
In the recent build test of linux-next, Stephen saw a build error
caused by a broken .tmp_versions/*.mod file:
https://lkml.org/lkml/2019/5/13/991
drivers/net/phy/asix.ko and drivers/net/usb/asix.ko have the same
basename, and there is a race in generating .tmp_versions/asix.mod
Kbuild has not checked this before, and it suddenly shows up with
obscure error messages when this kind of race occurs.
Non-unique module names cause various sort of problems, but it is
not trivial to catch them by eyes.
Hence, this script.
It checks not only real modules, but also built-in modules (i.e.
controlled by tristate CONFIG option, but currently compiled with =y).
Non-unique names for built-in modules also cause problems because
/sys/modules/ would fall over.
For the latest kernel, I tested "make allmodconfig all" (or more
quickly "make allyesconfig modules"), and it detected the following:
warning: same basename if the following are built as modules:
drivers/regulator/88pm800.ko
drivers/mfd/88pm800.ko
warning: same basename if the following are built as modules:
drivers/gpu/drm/bridge/adv7511/adv7511.ko
drivers/media/i2c/adv7511.ko
warning: same basename if the following are built as modules:
drivers/net/phy/asix.ko
drivers/net/usb/asix.ko
warning: same basename if the following are built as modules:
fs/coda/coda.ko
drivers/media/platform/coda/coda.ko
warning: same basename if the following are built as modules:
drivers/net/phy/realtek.ko
drivers/net/dsa/realtek.ko
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
If the compiler specified by $(CC) is not present, the Kconfig stage
sprinkles 'not found' messages, then succeeds.
$ make CROSS_COMPILE=foo defconfig
/bin/sh: 1: foogcc: not found
/bin/sh: 1: foogcc: not found
*** Default configuration is based on 'x86_64_defconfig'
./scripts/gcc-version.sh: 17: ./scripts/gcc-version.sh: foogcc: not found
./scripts/gcc-version.sh: 18: ./scripts/gcc-version.sh: foogcc: not found
./scripts/gcc-version.sh: 19: ./scripts/gcc-version.sh: foogcc: not found
./scripts/gcc-version.sh: 17: ./scripts/gcc-version.sh: foogcc: not found
./scripts/gcc-version.sh: 18: ./scripts/gcc-version.sh: foogcc: not found
./scripts/gcc-version.sh: 19: ./scripts/gcc-version.sh: foogcc: not found
./scripts/clang-version.sh: 11: ./scripts/clang-version.sh: foogcc: not found
./scripts/gcc-plugin.sh: 11: ./scripts/gcc-plugin.sh: foogcc: not found
init/Kconfig:16:warning: 'GCC_VERSION': number is invalid
#
# configuration written to .config
#
Terminate parsing files immediately if $(CC) or $(LD) is not found.
"make *config" will fail more nicely.
$ make CROSS_COMPILE=foo defconfig
*** Default configuration is based on 'x86_64_defconfig'
scripts/Kconfig.include:34: compiler 'foogcc' not found
make[1]: *** [scripts/kconfig/Makefile;82: defconfig] Error 1
make: *** [Makefile;557: defconfig] Error 2
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
syncconfig is responsible for keeping auto.conf up-to-date, so if it
fails for any reason, the build must be terminated immediately.
However, since commit 9390dff66a ("kbuild: invoke syncconfig if
include/config/auto.conf.cmd is missing"), Kbuild continues running
even after syncconfig fails.
You can confirm this by intentionally making syncconfig error out:
diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c
index 08ba146..307b9de 100644
--- a/scripts/kconfig/confdata.c
+++ b/scripts/kconfig/confdata.c
@@ -1023,6 +1023,9 @@ int conf_write_autoconf(int overwrite)
FILE *out, *tristate, *out_h;
int i;
+ if (overwrite)
+ return 1;
+
if (!overwrite && is_present(autoconf_name))
return 0;
Then, syncconfig fails, but Make would not stop:
$ make -s mrproper allyesconfig defconfig
$ make
scripts/kconfig/conf --syncconfig Kconfig
*** Error during sync of the configuration.
make[2]: *** [scripts/kconfig/Makefile;69: syncconfig] Error 1
make[1]: *** [Makefile;557: syncconfig] Error 2
make: *** [include/config/auto.conf.cmd] Deleting file 'include/config/tristate.conf'
make: Failed to remake makefile 'include/config/auto.conf'.
SYSTBL arch/x86/include/generated/asm/syscalls_32.h
SYSHDR arch/x86/include/generated/asm/unistd_32_ia32.h
SYSHDR arch/x86/include/generated/asm/unistd_64_x32.h
SYSTBL arch/x86/include/generated/asm/syscalls_64.h
[ continue running ... ]
The reason is in the behavior of a pattern rule with multi-targets.
%/auto.conf %/auto.conf.cmd %/tristate.conf: $(KCONFIG_CONFIG)
$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
GNU Make knows this rule is responsible for making all the three files
simultaneously. As far as examined, auto.conf.cmd is the target in
question when this rule is invoked. It is probably because auto.conf.cmd
is included below the inclusion of auto.conf.
The inclusion of auto.conf is mandatory, while that of auto.conf.cmd
is optional. GNU Make does not care about the failure in the process
of updating optional include files.
I filed this issue (https://savannah.gnu.org/bugs/?56301) in case this
behavior could be improved somehow in future releases of GNU Make.
Anyway, it is quite easy to fix our Makefile.
Given that auto.conf is already a mandatory include file, there is no
reason to stick auto.conf.cmd optional. Make it mandatory as well.
Cc: linux-stable <stable@vger.kernel.org> # 5.0+
Fixes: 9390dff66a ("kbuild: invoke syncconfig if include/config/auto.conf.cmd is missing")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
We do not support old Clang versions. Upgrade your clang version
if any of these flags is unsupported.
Let's add all flags inside ifdef CONFIG_CC_IS_CLANG unconditionally.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Sedat Dilek <sedat.dilek@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
This is no longer a valid option in clang, it was removed in 3.5, which
we don't support.
cb3f812b6b
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
This flag is documented in the GCC 4.6 manual, and recognized by
Clang as well. Let's rip off the cc-option switch.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Sedat Dilek <sedat.dilek@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
This warning was disabled by commit bd664f6b3e ("disable new
gcc-7.1.1 warnings for now") just because it was too noisy.
Thanks to Arnd Bergmann, all warnings have been fixed. Now, we are
ready to re-enable it.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnd Bergmann <arnd@arndb.de>
- allow users to invoke 'make' out of the source tree
- refactor scripts/mkmakefile
- deprecate KBUILD_SRC, which was used to track the source tree
location for O= build.
- fix recordmcount.pl in case objdump output is localized
- turn unresolved symbols in external modules to errors from warnings
by default; pass KBUILD_MODPOST_WARN=1 to get them back to warnings
- generate modules.builtin.modinfo to collect .modinfo data from
built-in modules
- misc Makefile cleanups
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Merge tag 'kbuild-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- allow users to invoke 'make' out of the source tree
- refactor scripts/mkmakefile
- deprecate KBUILD_SRC, which was used to track the source tree
location for O= build.
- fix recordmcount.pl in case objdump output is localized
- turn unresolved symbols in external modules to errors from warnings
by default; pass KBUILD_MODPOST_WARN=1 to get them back to warnings
- generate modules.builtin.modinfo to collect .modinfo data from
built-in modules
- misc Makefile cleanups
* tag 'kbuild-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (21 commits)
.gitignore: add more all*.config patterns
moduleparam: Save information about built-in modules in separate file
Remove MODULE_ALIAS() calls that take undefined macro
.gitignore: add leading and trailing slashes to generated directories
scripts/tags.sh: fix direct execution of scripts/tags.sh
scripts: override locale from environment when running recordmcount.pl
samples: kobject: allow CONFIG_SAMPLE_KOBJECT to become y
samples: seccomp: turn CONFIG_SAMPLE_SECCOMP into a bool option
kbuild: move Documentation to vmlinux-alldirs
kbuild: move samples/ to KBUILD_VMLINUX_OBJS
modpost: make KBUILD_MODPOST_WARN also configurable for external modules
kbuild: check arch/$(SRCARCH)/include/generated before out-of-tree build
kbuild: remove unneeded dependency for include/config/kernel.release
memory: squash drivers/memory/Makefile.asm-offsets
kbuild: use $(srctree) instead of KBUILD_SRC to check out-of-tree build
kbuild: mkmakefile: generate a simple wrapper of top Makefile
kbuild: mkmakefile: do not check the generated Makefile marker
kbuild: allow Kbuild to start from any directory
kbuild: pass $(MAKECMDGOALS) to sub-make as is
kbuild: fix warning "overriding recipe for target 'Makefile'"
...
Pull networking updates from David Miller:
"Highlights:
1) Support AES128-CCM ciphers in kTLS, from Vakul Garg.
2) Add fib_sync_mem to control the amount of dirty memory we allow to
queue up between synchronize RCU calls, from David Ahern.
3) Make flow classifier more lockless, from Vlad Buslov.
4) Add PHY downshift support to aquantia driver, from Heiner
Kallweit.
5) Add SKB cache for TCP rx and tx, from Eric Dumazet. This reduces
contention on SLAB spinlocks in heavy RPC workloads.
6) Partial GSO offload support in XFRM, from Boris Pismenny.
7) Add fast link down support to ethtool, from Heiner Kallweit.
8) Use siphash for IP ID generator, from Eric Dumazet.
9) Pull nexthops even further out from ipv4/ipv6 routes and FIB
entries, from David Ahern.
10) Move skb->xmit_more into a per-cpu variable, from Florian
Westphal.
11) Improve eBPF verifier speed and increase maximum program size,
from Alexei Starovoitov.
12) Eliminate per-bucket spinlocks in rhashtable, and instead use bit
spinlocks. From Neil Brown.
13) Allow tunneling with GUE encap in ipvs, from Jacky Hu.
14) Improve link partner cap detection in generic PHY code, from
Heiner Kallweit.
15) Add layer 2 encap support to bpf_skb_adjust_room(), from Alan
Maguire.
16) Remove SKB list implementation assumptions in SCTP, your's truly.
17) Various cleanups, optimizations, and simplifications in r8169
driver. From Heiner Kallweit.
18) Add memory accounting on TX and RX path of SCTP, from Xin Long.
19) Switch PHY drivers over to use dynamic featue detection, from
Heiner Kallweit.
20) Support flow steering without masking in dpaa2-eth, from Ioana
Ciocoi.
21) Implement ndo_get_devlink_port in netdevsim driver, from Jiri
Pirko.
22) Increase the strict parsing of current and future netlink
attributes, also export such policies to userspace. From Johannes
Berg.
23) Allow DSA tag drivers to be modular, from Andrew Lunn.
24) Remove legacy DSA probing support, also from Andrew Lunn.
25) Allow ll_temac driver to be used on non-x86 platforms, from Esben
Haabendal.
26) Add a generic tracepoint for TX queue timeouts to ease debugging,
from Cong Wang.
27) More indirect call optimizations, from Paolo Abeni"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1763 commits)
cxgb4: Fix error path in cxgb4_init_module
net: phy: improve pause mode reporting in phy_print_status
dt-bindings: net: Fix a typo in the phy-mode list for ethernet bindings
net: macb: Change interrupt and napi enable order in open
net: ll_temac: Improve error message on error IRQ
net/sched: remove block pointer from common offload structure
net: ethernet: support of_get_mac_address new ERR_PTR error
net: usb: smsc: fix warning reported by kbuild test robot
staging: octeon-ethernet: Fix of_get_mac_address ERR_PTR check
net: dsa: support of_get_mac_address new ERR_PTR error
net: dsa: sja1105: Fix status initialization in sja1105_get_ethtool_stats
vrf: sit mtu should not be updated when vrf netdev is the link
net: dsa: Fix error cleanup path in dsa_init_module
l2tp: Fix possible NULL pointer dereference
taprio: add null check on sched_nest to avoid potential null pointer dereference
net: mvpp2: cls: fix less than zero check on a u32 variable
net_sched: sch_fq: handle non connected flows
net_sched: sch_fq: do not assume EDT packets are ordered
net: hns3: use devm_kcalloc when allocating desc_cb
net: hns3: some cleanup for struct hns3_enet_ring
...
- Consolidate memory initialization Kconfigs (Kees)
- Implement support for Clang's stack variable auto-init (Alexander)
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Merge tag 'meminit-v5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull compiler-based variable initialization updates from Kees Cook:
"This is effectively part of my gcc-plugins tree, but as this adds some
Clang support, it felt weird to still call it "gcc-plugins". :)
This consolidates Kconfig for the existing stack variable
initialization (via structleak and stackleak gcc plugins) and adds
Alexander Potapenko's support for Clang's new similar functionality.
Summary:
- Consolidate memory initialization Kconfigs (Kees)
- Implement support for Clang's stack variable auto-init (Alexander)"
* tag 'meminit-v5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
security: Implement Clang's stack initialization
security: Move stackleak config to Kconfig.hardening
security: Create "kernel hardening" config area
Pull livepatching updates from Jiri Kosina:
- livepatching kselftests improvements from Joe Lawrence and Miroslav
Benes
- making use of gcc's -flive-patching option when available, from
Miroslav Benes
- kobject handling cleanups, from Petr Mladek
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching:
livepatch: Remove duplicated code for early initialization
livepatch: Remove custom kobject state handling
livepatch: Convert error about unsupported reliable stacktrace into a warning
selftests/livepatch: Add functions.sh to TEST_PROGS_EXTENDED
kbuild: use -flive-patching when CONFIG_LIVEPATCH is enabled
selftests/livepatch: use TEST_PROGS for test scripts
Problem:
When a kernel module is compiled as a separate module, some important
information about the kernel module is available via .modinfo section of
the module. In contrast, when the kernel module is compiled into the
kernel, that information is not available.
Information about built-in modules is necessary in the following cases:
1. When it is necessary to find out what additional parameters can be
passed to the kernel at boot time.
2. When you need to know which module names and their aliases are in
the kernel. This is very useful for creating an initrd image.
Proposal:
The proposed patch does not remove .modinfo section with module
information from the vmlinux at the build time and saves it into a
separate file after kernel linking. So, the kernel does not increase in
size and no additional information remains in it. Information is stored
in the same format as in the separate modules (null-terminated string
array). Because the .modinfo section is already exported with a separate
modules, we are not creating a new API.
It can be easily read in the userspace:
$ tr '\0' '\n' < modules.builtin.modinfo
ext4.softdep=pre: crc32c
ext4.license=GPL
ext4.description=Fourth Extended Filesystem
ext4.author=Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others
ext4.alias=fs-ext4
ext4.alias=ext3
ext4.alias=fs-ext3
ext4.alias=ext2
ext4.alias=fs-ext2
md_mod.alias=block-major-9-*
md_mod.alias=md
md_mod.description=MD RAID framework
md_mod.license=GPL
md_mod.parmtype=create_on_open:bool
md_mod.parmtype=start_dirty_degraded:int
...
Co-Developed-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Signed-off-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Signed-off-by: Alexey Gladkov <gladkov.alexey@gmail.com>
Acked-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Handle samples/ like the other top-level directories to simplify
the Makefile.
Include include/config/auto.conf earlier to evaluate
drivers-$(CONFIG_SAMPLES).
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
We already did this for clang, but now gcc has that warning too. Yes,
yes, the address may be unaligned. And that's kind of the point.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
CONFIG_INIT_STACK_ALL turns on stack initialization based on
-ftrivial-auto-var-init in Clang builds, which has greater coverage
than CONFIG_GCC_PLUGINS_STRUCTLEAK_BYREF_ALL.
-ftrivial-auto-var-init Clang option provides trivial initializers for
uninitialized local variables, variable fields and padding.
It has three possible values:
pattern - uninitialized locals are filled with a fixed pattern
(mostly 0xAA on 64-bit platforms, see https://reviews.llvm.org/D54604
for more details, but 0x000000AA for 32-bit pointers) likely to cause
crashes when uninitialized value is used;
zero (it's still debated whether this flag makes it to the official
Clang release) - uninitialized locals are filled with zeroes;
uninitialized (default) - uninitialized locals are left intact.
This patch uses only the "pattern" mode when CONFIG_INIT_STACK_ALL is
enabled.
Developers have the possibility to opt-out of this feature on a
per-variable basis by using __attribute__((uninitialized)), but such
use should be well justified in comments.
Co-developed-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Alexander Potapenko <glider@google.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Daniel Borkmann says:
====================
pull-request: bpf-next 2019-04-12
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Improve BPF verifier scalability for large programs through two
optimizations: i) remove verifier states that are not useful in pruning,
ii) stop walking parentage chain once first LIVE_READ is seen. Combined
gives approx 20x speedup. Increase limits for accepting large programs
under root, and add various stress tests, from Alexei.
2) Implement global data support in BPF. This enables static global variables
for .data, .rodata and .bss sections to be properly handled which allows
for more natural program development. This also opens up the possibility
to optimize program workflow by compiling ELFs only once and later only
rewriting section data before reload, from Daniel and with test cases and
libbpf refactoring from Joe.
3) Add config option to generate BTF type info for vmlinux as part of the
kernel build process. DWARF debug info is converted via pahole to BTF.
Latter relies on libbpf and makes use of BTF deduplication algorithm which
results in 100x savings compared to DWARF data. Resulting .BTF section is
typically about 2MB in size, from Andrii.
4) Add BPF verifier support for stack access with variable offset from
helpers and add various test cases along with it, from Andrey.
5) Extend bpf_skb_adjust_room() growth BPF helper to mark inner MAC header
so that L2 encapsulation can be used for tc tunnels, from Alan.
6) Add support for input __sk_buff context in BPF_PROG_TEST_RUN so that
users can define a subset of allowed __sk_buff fields that get fed into
the test program, from Stanislav.
7) Add bpf fs multi-dimensional array tests for BTF test suite and fix up
various UBSAN warnings in bpftool, from Yonghong.
8) Generate a pkg-config file for libbpf, from Luca.
9) Dump program's BTF id in bpftool, from Prashant.
10) libbpf fix to use smaller BPF log buffer size for AF_XDP's XDP
program, from Magnus.
11) kallsyms related fixes for the case when symbols are not present in
BPF selftests and samples, from Daniel
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
After cross-compiling the kernel, "make mrproper" should be executed
with the proper ARCH= option. Otherwise, stale objects will remain
under arch/$(SRCARCH)/.
One bad scenario is like this:
$ make ARCH=arm defconfig all # cross-compile the kernel for arm
$ make mrproper # mrproper for host-arch (i.e. x86)
$ make ARCH=arm O=build_dir defconfig all
If you miss ARCH= for mrproper and cross-compile the kernel with O=
and ARCH= options, Kbuild will happily start to build, but may fail
due to stale objects in the srctree.
If $(srctree)/arch/$(SRCARCH)/include/generated/ exists, let's stop
the out-of-tree build. To detect this, mrproper should clean only
arch/$(SRCARCH)/include/generated/.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
This is unneeded since commit 43fee2b238 ("kbuild: do not redirect
the first prerequisite for filechk").
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
GCC 9 introduces a new option, -flive-patching. It disables certain
optimizations which could make a compilation unsafe for later live
patching of the running kernel.
The option is used only if CONFIG_LIVEPATCH is enabled and $(CC)
supports it.
Performance impact of the option was measured on three different
Intel machines - two bigger NUMA boxes and one smaller UMA box. Kernel
intensive (IO, scheduling, networking) benchmarks were selected, plus a
set of HPC workloads from NAS Parallel Benchmark. The tests were done on
upstream kernel 5.0-rc8 with openSUSE Leap 15.0 userspace.
The majority of the tests is unaffected. The only significant exception
is the scheduler section which suffers 1-3% degradation.
Evaluated-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
This patch adds new config option to trigger generation of BTF type
information from DWARF debuginfo for vmlinux and kernel modules through
pahole, which in turn relies on libbpf for btf_dedup() algorithm.
The intent is to record compact type information of all types used
inside kernel, including all the structs/unions/typedefs/etc. This
enables BPF's compile-once-run-everywhere ([0]) approach, in which
tracing programs that are inspecting kernel's internal data (e.g.,
struct task_struct) can be compiled on a system running some kernel
version, but would be possible to run on other kernel versions (and
configurations) without recompilation, even if the layout of structs
changed and/or some of the fields were added, removed, or renamed.
This is only possible if BPF loader can get kernel type info to adjust
all the offsets correctly. This patch is a first time in this direction,
making sure that BTF type info is part of Linux kernel image in
non-loadable ELF section.
BTF deduplication ([1]) algorithm typically provides 100x savings
compared to DWARF data, so resulting .BTF section is not big as is
typically about 2MB in size.
[0] http://vger.kernel.org/lpc-bpf2018.html#session-2
[1] https://facebookmicrosites.github.io/bpf/blog/2018/11/14/btf-enhancement.html
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
KBUILD_SRC was conventionally used for some different purposes:
[1] To remember the source tree path
[2] As a flag to check if sub-make is already done
[3] As a flag to check if Kbuild runs out of tree
For [1], we do not need to remember it because the top Makefile
can compute it by $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
[2] has been replaced with self-commenting 'sub_make_done'.
For [3], we can distinguish in-tree/out-of-tree by comparing
$(srctree) and '.'
This commit converts [3] to prepare for the KBUILD_SRC removal.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Kbuild always runs in the top of the output directory.
If Make starts in the source directory with O=, it relocates the
working directory to the location specified by O=.
Also, users can start build from the output directory by using the
Makefile generated by scripts/mkmakefile.
With a little more effort, Kbuild will be able to start from any
directory path.
This commit allows to specify the source directory by using
the -f option.
For example, you can do:
$ cd path/to/output/dir
$ make -f path/to/source/dir/Makefile
Or, for the equivalent behavior, you can do:
$ make O=path/to/output/dir -f path/to/source/dir/Makefile
KBUILD_SRC is now deprecated.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kieran Bingham <kbingham@kernel.org>
Manipulating $(MAKECMDGOALS) for sub-make seems odd to me.
[1] 'make O=foo sub-make' is turned into 'make O=foo', which builds
the default targets. It would make sense to terminate the build with:
*** No rule to make target 'sub-make'. Stop.
[2] 'make O=foo defconfig _all' is turned into 'make O=foo defconfig',
which changes the behavior.
Let's pass $(MAKECMDGOALS) as is.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
If you do "make Makefile" with GNU Make 3.x, the following warning
is displayed:
$ make Makefile
Makefile:165: warning: overriding recipe for target 'Makefile'
Makefile:51: warning: ignoring old recipe for target 'Makefile'
make[1]: Nothing to be done for 'Makefile'.
make: Nothing to be done for 'Makefile'.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
When you run a "make *config" target, the retpoline compiler flags
are evaluated for nothing because the code is located above the
'ifeq ($(config-targets),1)'.
Move it a bit below to avoid unneeded computation in the Kconfig stage.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Pull core fixes from Thomas Gleixner:
"A small set of core updates:
- Make the watchdog respect the selected CPU mask again. That was
broken by the rework of the watchdog thread management and caused
inconsistent state and NMI watchdog being unstoppable.
- Ensure that the objtool build can find the libelf location.
- Remove dead kcore stub code"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
watchdog: Respect watchdog cpumask on CPU hotplug
objtool: Query pkg-config for libelf location
proc/kcore: Remove unused kclist_add_remap()
- Remove harmful -Oz option of Clang
- Get back the original behavior (no recursion for in-tree build)
for GNU Make 4.x
- Some minor fixes for coccinelle patches
- Do not overwrite .gitignore in the output directory in case
it is version-controlled
- Fix missed record-mcount bug for dynamic ftrace
- Fix endianness bug in modversions for relative CRC
- Cater to '^H' key code in Kconfig ncurses programs
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Merge tag 'kbuild-fixes-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:
- Remove harmful -Oz option of Clang
- Get back the original behavior (no recursion for in-tree build) for
GNU Make 4.x
- Some minor fixes for coccinelle patches
- Do not overwrite .gitignore in the output directory in case it is
version-controlled
- Fix missed record-mcount bug for dynamic ftrace
- Fix endianness bug in modversions for relative CRC
- Cater to '^H' key code in Kconfig ncurses programs
* tag 'kbuild-fixes-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kconfig/[mn]conf: handle backspace (^H) key
kbuild: modversions: Fix relative CRC byte order interpretation
scripts: coccinelle: Fix description of badty.cocci
kbuild: strip whitespace in cmd_record_mcount findstring
kbuild: do not overwrite .gitignore in output directory
kbuild: skip parsing pre sub-make code for recursion
coccinelle: put_device: reduce false positives
kbuild: skip sub-make for in-tree build with GNU Make 4.x
Revert "kbuild: use -Oz instead of -Os when using clang"
Commit 3a51ff3442 ("kbuild: gitignore output directory") seemed to
bother people who version-control output directories.
Andre Przywara says:
"Unfortunately this breaks my setup, because I keep a totally separate
git repository in my build directories to track (various versions of)
.config. So .gitignore there is carefully crafted to ignore most build
artefacts, but not .config, for instance."
Link: https://lkml.org/lkml/2019/3/22/1819
Reported-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
When Make recurses to the top Makefile with sub-make-done unset,
the code block surrounded by 'ifneq ($(sub-make-done),1) ... endif'
is parsed multiple times. This happens for in-tree building of
include/config/auto.conf, *-pkg, etc. with GNU Make 4.x.
This is a slight regression by commit 688931a5ad ("kbuild: skip
sub-make for in-tree build with GNU Make 4.x") in terms of performance
since that code block contains one $(shell ...) invocation.
Fix it by exporting the variable irrespective of sub-make being run.
I renamed it because GNU Make cannot properly export variables
containing hyphens. This is probably a bug of GNU Make, and the issue
in Kbuild had already been reported by commit 2bfbe7881e ("kbuild:
Do not use hyphen in exported variable name").
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Commit 2b50f7ab63 ("kbuild: add workaround for Debian make-kpkg")
annoyed people who want to wrap the top Makefile with GNUmakefile
to customize it for their use.
On second thought, we do not need to run the sub-make for in-tree
build with Make 4.x because the 'MAKEFLAGS += -rR' issue only happens
on GNU Make 3.x.
With this commit, people will get back their workflow, and the Debian
make-kpkg will still work.
Fixes: 2b50f7ab63 ("kbuild: add workaround for Debian make-kpkg")
Reported-by: Andreas Schwab <schwab@suse.de>
Reported-by: David Howells <dhowells@redhat.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Andreas Schwab <schwab@suse.de>
Tested-by: David Howells <dhowells@redhat.com>
The clang option -Oz enables *aggressive* optimization for size,
which doesn't necessarily result in smaller images, but can have
negative impact on performance. Switch back to the less aggressive
-Os.
This reverts commit 6748cb3c29.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
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>
During a simple no-op (nothing changed) build I saw 39 invocations of
the C compiler with the argument "-print-file-name=include". We don't
need to call the C compiler 39 times for this--one time will suffice.
Let's change NOSTDINC_FLAGS to a simply expanded variable to avoid
this since there doesn't appear to be any reason it should be
recursively expanded.
On my build this shaved ~400 ms off my "no-op" build.
Note that the recursive expansion seems to date back to the (really
old) commit e8f5bdb02c ("[PATCH] Makefile include path ordering").
It's a little unclear to me if the point of that patch was to switch
the variable to be recursively expanded (which it did) or to avoid
directly assigning to NOSTDINC_FLAGS (AKA to switch to +=) because
someone else (out of tree?) was setting it. I presume later since if
the only goal was to switch to recursive expansion the patch would
have just removed the ":".
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Since commit 3812b8c5c5 ("kbuild: make -r/-R effective in top
Makefile for old Make versions"), make-kpkg is not working.
make-kpkg directly includes the top Makefile of Linux kernel, and
appends some debian_* targets.
/usr/share/kernel-package/ruleset/kernel_version.mk:
# Include the kernel makefile
override dot-config := 1
include Makefile
dot-config := 1
I did not know the kernel Makefile was used in that way, and it is
hard to guarantee the behavior when the kernel Makefile is included
by another Makefile from a different project.
It looks like Debian Stretch stopped providing make-kpkg. Maybe it is
obsolete and being replaced with 'make deb-pkg' etc. but still widely
used.
This commit adds a workaround; if the top Makefile is included by
another Makefile, skip sub-make in order to make the main part visible.
'MAKEFLAGS += -rR' does not become effective for GNU Make < 4.0, but
Debian/Ubuntu is already using newer versions.
The effect of this commit:
Debian 8 (Jessie) : Fixed
Debian 9 (Stretch) : make-kpkg (kernel-package) is not provided
Ubuntu 14.04 LTS : NOT Fixed
Ubuntu 16.04 LTS : Fixed
Ubuntu 18.04 LTS : Fixed
This commit cannot fix Ubuntu 14.04 because it installs GNU Make 3.81,
but its support will end in Apr 2019, which is before the Linux v5.1
release.
I added warning so that nobody would try to include the top Makefile.
Fixes: 3812b8c5c5 ("kbuild: make -r/-R effective in top Makefile for old Make versions")
Reported-by: Liz Zhang <lizzha@microsoft.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Lili Deng <v-lide@microsoft.com>
Cc: Manoj Srivastava <srivasta@debian.org>
- do not generate unneeded top-level built-in.a
- let git ignore O= directory entirely
- optimize scripts/kallsyms slightly
- exclude DWARF info from *.s regardless of config options
- fix GCC toolchain search path for Clang to prepare ld.lld support
- do not generate modules.order when CONFIG_MODULES is disabled
- simplify single target rules and remove VPATH for external module build
- allow to add optional flags to dpkg-buildpackage when building deb-pkg
- move some compiler option tests from Makefile to Kconfig
- various Makefile cleanups
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Merge tag 'kbuild-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- do not generate unneeded top-level built-in.a
- let git ignore O= directory entirely
- optimize scripts/kallsyms slightly
- exclude DWARF info from *.s regardless of config options
- fix GCC toolchain search path for Clang to prepare ld.lld support
- do not generate modules.order when CONFIG_MODULES is disabled
- simplify single target rules and remove VPATH for external module
build
- allow to add optional flags to dpkg-buildpackage when building
deb-pkg
- move some compiler option tests from Makefile to Kconfig
- various Makefile cleanups
* tag 'kbuild-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (40 commits)
kbuild: remove scripts/basic/% build target
kbuild: use -Werror=implicit-... instead of -Werror-implicit-...
kbuild: clean up scripts/gcc-version.sh
kbuild: remove cc-version macro
kbuild: update comment block of scripts/clang-version.sh
kbuild: remove commented-out INITRD_COMPRESS
kbuild: move -gsplit-dwarf, -gdwarf-4 option tests to Kconfig
kbuild: [bin]deb-pkg: add DPKG_FLAGS variable
kbuild: move ".config not found!" message from Kconfig to Makefile
kbuild: invoke syncconfig if include/config/auto.conf.cmd is missing
kbuild: simplify single target rules
kbuild: remove empty rules for makefiles
kbuild: make -r/-R effective in top Makefile for old Make versions
kbuild: move tools_silent to a more relevant place
kbuild: compute false-positive -Wmaybe-uninitialized cases in Kconfig
kbuild: refactor cc-cross-prefix implementation
kbuild: hardcode genksyms path and remove GENKSYMS variable
scripts/gdb: refactor rules for symlink creation
kbuild: create symlink to vmlinux-gdb.py in scripts_gdb target
scripts/gdb: do not descend into scripts/gdb from scripts
...
Here is the big driver core patchset for 5.1-rc1
More patches than "normal" here this merge window, due to some work in
the driver core by Alexander Duyck to rework the async probe
functionality to work better for a number of devices, and independant
work from Rafael for the device link functionality to make it work
"correctly".
Also in here is:
- lots of BUS_ATTR() removals, the macro is about to go away
- firmware test fixups
- ihex fixups and simplification
- component additions (also includes i915 patches)
- lots of minor coding style fixups and cleanups.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the big driver core patchset for 5.1-rc1
More patches than "normal" here this merge window, due to some work in
the driver core by Alexander Duyck to rework the async probe
functionality to work better for a number of devices, and independant
work from Rafael for the device link functionality to make it work
"correctly".
Also in here is:
- lots of BUS_ATTR() removals, the macro is about to go away
- firmware test fixups
- ihex fixups and simplification
- component additions (also includes i915 patches)
- lots of minor coding style fixups and cleanups.
All of these have been in linux-next for a while with no reported
issues"
* tag 'driver-core-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (65 commits)
driver core: platform: remove misleading err_alloc label
platform: set of_node in platform_device_register_full()
firmware: hardcode the debug message for -ENOENT
driver core: Add missing description of new struct device_link field
driver core: Fix PM-runtime for links added during consumer probe
drivers/component: kerneldoc polish
async: Add cmdline option to specify drivers to be async probed
driver core: Fix possible supplier PM-usage counter imbalance
PM-runtime: Fix __pm_runtime_set_status() race with runtime resume
driver: platform: Support parsing GpioInt 0 in platform_get_irq()
selftests: firmware: fix verify_reqs() return value
Revert "selftests: firmware: remove use of non-standard diff -Z option"
Revert "selftests: firmware: add CONFIG_FW_LOADER_USER_HELPER_FALLBACK to config"
device: Fix comment for driver_data in struct device
kernfs: Allocating memory for kernfs_iattrs with kmem_cache.
sysfs: remove unused include of kernfs-internal.h
driver core: Postpone DMA tear-down until after devres release
driver core: Document limitation related to DL_FLAG_RPM_ACTIVE
PM-runtime: Take suppliers into account in __pm_runtime_set_status()
device.h: Add __cold to dev_<level> logging functions
...
This build rule was introduced by commit cd05e6bdc6 ("[PATCH]
kbuild: fix split-include dependency") to handle the dependency of
scripts/basic/split-include.
Now, fixdep is the only tool in scripts/basic/, and this rule is
no longer used.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The flag '-Werror-implicit-function-declaration', present in GCC 2.95,
stopped to be documented in GCC 4.3, replaced by the more generic
'-Werror=...' form.
So, use the equivalent '-Werror=implicit-function-declaration' instead.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
This code has been commented out since commit b7000adef1
("Don't set the INITRD_COMPRESS environment variable automatically").
Clean it up now.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
CONFIG_DEBUG_INFO_SPLIT and CONFIG_DEBUG_INFO_DWARF4 enable extra
dwarf options if supported. You never know if they are really enabled
since Makefile may silently turn them off.
The actual behavior will match to the kernel configuration by
testing those compiler flags in the Kconfig stage.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
If you run "make" in a pristine source tree, currently Kbuild will
start to build Kconfig to let it show the error message.
It would be more straightforward to check it in Makefile and let
it fail immediately.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
If include/config/auto.conf.cmd is lost for some reasons, it is not
self-healing, so the top Makefile misses to run syncconfig.
Move include/config/auto.conf.cmd to the target side.
I used a pattern rule instead of a normal rule here although it is
a bit gross.
If the rule were written with a normal rule like this,
include/config/auto.conf \
include/config/auto.conf.cmd \
include/config/tristate.conf: $(KCONFIG_CONFIG)
$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
... syncconfig would be executed per target.
Using a pattern rule makes sure that syncconfig is executed just once
because Make assumes the recipe will create all of the targets.
Here is a quote from the GNU Make manual [1]:
"Pattern rules may have more than one target. Unlike normal rules,
this does not act as many different rules with the same prerequisites
and recipe. If a pattern rule has multiple targets, make knows that
the rule's recipe is responsible for making all of the targets. The
recipe is executed only once to make all the targets. When searching
for a pattern rule to match a target, the target patterns of a rule
other than the one that matches the target in need of a rule are
incidental: make worries only about giving a recipe and prerequisites
to the file presently in question. However, when this file's recipe is
run, the other targets are marked as having been updated themselves."
[1]: https://www.gnu.org/software/make/manual/html_node/Pattern-Intro.html
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The dependency will be checked anyway after Kbuild descends into a
sub-directory. Skip object/source dependency checks in top Makefile.
VPATH can be simpler since the top Makefile no longer checks the
presence of the source file, which is located in in the external
module directory.
One good thing is, it can compile an object from a generated source
file.
$ make crypto/rsapubkey.asn1.o
...
ASN.1 crypto/rsapubkey.asn1.c
CC crypto/rsapubkey.asn1.o
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The previous commit made 'MAKEFLAGS += -rR' effective in the top
Makefile regardless of O= option, GNU Make versions.
The top Makefile does not need to cancel implicit rules for makefiles.
There is still one place where an empty rule is useful. Since -rR is
effective only after sub-make, GNU Make would try implicit rules to
update the top Makefile. Although it is not a big overhead, cancel it
just in case.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Adding -rR to MAKEFLAGS is important because we do not want to
be bothered by built-in implicit rules or variables.
One problem that used to exist in older GNU Make versions is
MAKEFLAGS += -rR
... does not become effective in the current Makefile. When you are
building with O= option, it becomes effective in the top Makefile
since it recurses via 'sub-make' target. Otherwise, the top Makefile
tries implicit rules. That is why we explicitly add empty rules for
Makefiles, but we often miss to do that.
In fact, adding -d option to older GNU Make versions shows it is
trying a bunch of implicit pattern rules.
Considering target file `scripts/Makefile.kcov'.
Looking for an implicit rule for `scripts/Makefile.kcov'.
Trying pattern rule with stem `Makefile.kcov'.
Trying implicit prerequisite `scripts/Makefile.kcov.o'.
Trying pattern rule with stem `Makefile.kcov'.
Trying implicit prerequisite `scripts/Makefile.kcov.c'.
Trying pattern rule with stem `Makefile.kcov'.
Trying implicit prerequisite `scripts/Makefile.kcov.cc'.
Trying pattern rule with stem `Makefile.kcov'.
Trying implicit prerequisite `scripts/Makefile.kcov.C'.
...
This issue was fixed by GNU Make commit 58dae243526b ("[Savannah #20501]
Handle adding -r/-R to MAKEFLAGS in the makefile"). So, it is no longer
a problem if you use GNU Make 4.0 or later. However, older versions are
still widely used.
So, I decided to patch the kernel Makefile to invoke sub-make regardless
of O= option. This will allow further cleanups.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Since -Wmaybe-uninitialized was introduced by GCC 4.7, we have patched
various false positives:
- commit e74fc973b6 ("Turn off -Wmaybe-uninitialized when building
with -Os") turned off this option for -Os.
- commit 815eb71e71 ("Kbuild: disable 'maybe-uninitialized' warning
for CONFIG_PROFILE_ALL_BRANCHES") turned off this option for
CONFIG_PROFILE_ALL_BRANCHES
- commit a76bcf557e ("Kbuild: enable -Wmaybe-uninitialized warning
for "make W=1"") turned off this option for GCC < 4.9
Arnd provided more explanation in https://lkml.org/lkml/2017/3/14/903
I think this looks better by shifting the logic from Makefile to Kconfig.
Link: https://github.com/ClangBuiltLinux/linux/issues/350
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
The genksyms source was integrated into the kernel tree in 2003.
I do not expect anybody still using the external /sbin/genksyms.
Kbuild does not need to provide the ability to override GENKSYMS.
Let's remove the GENKSYMS variable, and use the hardcoded path.
Since it occurred in the pre-git era, I attached the commit message
in case somebody is interested in the historical background.
| Author: Kai Germaschewski <kai@tp1.ruhr-uni-bochum.de>
| Date: Wed Feb 19 04:17:28 2003 -0600
|
| kbuild: [PATCH] put genksyms in scripts dir
|
| This puts genksyms into scripts/genksyms/.
|
| genksyms used to be maintained externally, though the only possible user
| was the kernel build. Moving it into the kernel sources makes it easier to
| keep it uptodate, like for example updating it to generate linker scripts
| directly instead of postprocessing the generated header file fragments
| with sed, as we do currently.
|
| Also, genksyms does not handle __typeof__, which needs to be fixed since
| some of the exported symbol in the kernel are defined using __typeof__.
|
| (Rusty Russell/me)
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
It is weird to create gdb stuff as a side-effect of vmlinux.
Move it to a more relevant place.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Currently, Kbuild descends from scripts/Makefile to scripts/gdb/Makefile
just for creating symbolic links, but it does not need to do it so early.
Merge the two descending paths to simplify the code.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
scripts/gdb/linux/constants.py is never used in the kernel build
process. There is no good reason to create it so early.
Get it out of the 'prepare' stage.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Commit 06300b21f4 ("kbuild: support building individual files for
external modules") introduced the '/' target. It works only for
external modules to build all .o files, but skip the modpost stage.
However, 'make /' looks a bit weird to me. 'make ./' is more sensible
if you want to build all objects under the current directory, and it
works as expected.
Let's change '/' into a phony target that is an alias of './', but
I may feel like deprecating it in the future.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
It is fine to set KBUILD_MODULES=1 when CONFIG_MODULES is disabled.
It is actually how "make allnoconfig all" works.
On the other hand, KBUILD_MODULES=1 is unneeded for the %.ko pattern.
It is just a matter of whether modules.order is generated or not.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
This causes an issue when trying to build with `make LD=ld.lld` if
ld.lld and the rest of your cross tools aren't in the same directory
(ex. /usr/local/bin) (as is the case for Android's build system), as the
GCC_TOOLCHAIN_DIR then gets set based on `which $(LD)` which will point
where LLVM tools are, not GCC/binutils tools are located.
Instead, select the GCC_TOOLCHAIN_DIR based on another tool provided by
binutils for which LLVM does not provide a substitute for, such as
elfedit.
Fixes: 785f11aa59 ("kbuild: Add better clang cross build support")
Link: https://github.com/ClangBuiltLinux/linux/issues/341
Suggested-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
When compiling into output directory using O=, many files
created under KBUILD_OUTPUT that git considers
as new ones; git clients, ex. "git gui" lists it, and it clutters
file list making it difficult to see what was really changed
Generate .gitignore in output directory that ignores all
its content
Signed-off-by: Vladimir Kondratiev <vladimir.kondratiev@linux.intel.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
There is no build order among the following:
prepare3
outputmakefile
asm-generic
$(version_h)
$(autoksyms_h)
include/generated/utsrelease.h
It is meaningless to insert the prepare2 target between the first
three and the last three.
The comment says, "prepare2 creates a makefile if using a separate
output directory." Let me explain it more precisely. The prepare
targets cannot be executed without the .config file. Because the
configuration targets depend on the outputmakefile target, the
generated makefile is already there before the parepare2 is run.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The top Makefile does not need to export KBUILD_VMLINUX_INIT and
KBUILD_VMLINUX_MAIN separately.
Put every built-in.a into KBUILD_VMLINUX_OBJS. The order of
$(head-y), $(init-y), $(core-y), ... is still retained.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Currently, the 'firmware' directory only contains a single Makefile
to embed extra firmware into the kernel.
Move it to the more relevant place.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit c3ff2a5193 ("powerpc/32: add stack protector support")
caused kernel panic on PowerPC when an external module is used with
CONFIG_STACKPROTECTOR because the 'prepare' target was not executed
for the external module build.
Commit e07db28eea ("kbuild: fix single target build for external
module") turned it into a build error because the 'prepare' target is
now executed but the 'prepare0' target is missing for the external
module build.
External module on arm/arm64 with CONFIG_STACKPROTECTOR_PER_TASK is
also broken in the same way.
Move 'PHONY += prepare0' to the common place. GNU Make is fine with
missing rule for phony targets. I also removed the comment which is
wrong irrespective of this commit.
I minimize the change so it can be easily backported to 4.20.x
To fix v4.20, please backport e07db28eea ("kbuild: fix single target
build for external module"), and then this commit.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=201891
Fixes: e07db28eea ("kbuild: fix single target build for external module")
Fixes: c3ff2a5193 ("powerpc/32: add stack protector support")
Fixes: 189af46571 ("ARM: smp: add support for per-task stack canaries")
Fixes: 0a1213fa74 ("arm64: enable per-task stack canaries")
Cc: linux-stable <stable@vger.kernel.org> # v4.20
Reported-by: Samuel Holland <samuel@sholland.org>
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
You do not have to use define ... endef for filechk_* rules.
For simple cases, the use of assignment looks cleaner, IMHO.
I updated the usage for scripts/Kbuild.include in case somebody
misunderstands the 'define ... endif' is the requirement.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
filechk_* rules often consist of multiple 'echo' lines. They must be
surrounded with { } or ( ) to work correctly. Otherwise, only the
string from the last 'echo' would be written into the target.
Let's take care of that in the 'filechk' in scripts/Kbuild.include
to clean up filechk_* rules.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Currently, CONFIG_JUMP_LABEL just means "I _want_ to use jump label".
The jump label is controlled by HAVE_JUMP_LABEL, which is defined
like this:
#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL)
# define HAVE_JUMP_LABEL
#endif
We can improve this by testing 'asm goto' support in Kconfig, then
make JUMP_LABEL depend on CC_HAS_ASM_GOTO.
Ugly #ifdef HAVE_JUMP_LABEL will go away, and CONFIG_JUMP_LABEL will
match to the real kernel capability.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Pull Devicetree updates from Rob Herring:
"The biggest highlight here is the start of using json-schema for DT
bindings. Being able to validate bindings has been discussed for years
with little progress.
- Initial support for DT bindings using json-schema language. This is
the start of converting DT bindings from free-form text to a
structured format.
- Reworking of initrd address initialization. This moves to using the
phys address instead of virt addr in the DT parsing code. This
rework was motivated by CONFIG_DEV_BLK_INITRD causing unnecessary
rebuilding of lots of files.
- Fix stale phandle entries in phandle cache
- DT overlay validation improvements. This exposed several memory
leak bugs which have been fixed.
- Use node name and device_type helper functions in DT code
- Last remaining conversions to using %pOFn printk specifier instead
of device_node.name directly
- Create new common RTC binding doc and move all trivial RTC devices
out of trivial-devices.txt.
- New bindings for Freescale MAG3110 magnetometer, Cadence Sierra
PHY, and Xen shared memory
- Update dtc to upstream version v1.4.7-57-gf267e674d145"
* tag 'devicetree-for-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (68 commits)
of: __of_detach_node() - remove node from phandle cache
of: of_node_get()/of_node_put() nodes held in phandle cache
gpio-omap.txt: add reg and interrupts properties
dt-bindings: mrvl,intc: fix a trivial typo
dt-bindings: iio: magnetometer: add dt-bindings for freescale mag3110
dt-bindings: Convert trivial-devices.txt to json-schema
dt-bindings: arm: mrvl: amend Browstone compatible string
dt-bindings: arm: Convert Tegra board/soc bindings to json-schema
dt-bindings: arm: Convert ZTE board/soc bindings to json-schema
dt-bindings: arm: Add missing Xilinx boards
dt-bindings: arm: Convert Xilinx board/soc bindings to json-schema
dt-bindings: arm: Convert VIA board/soc bindings to json-schema
dt-bindings: arm: Convert ST STi board/soc bindings to json-schema
dt-bindings: arm: Convert SPEAr board/soc bindings to json-schema
dt-bindings: arm: Convert CSR SiRF board/soc bindings to json-schema
dt-bindings: arm: Convert QCom board/soc bindings to json-schema
dt-bindings: arm: Convert TI nspire board/soc bindings to json-schema
dt-bindings: arm: Convert TI davinci board/soc bindings to json-schema
dt-bindings: arm: Convert Calxeda board/soc bindings to json-schema
dt-bindings: arm: Convert Altera board/soc bindings to json-schema
...
Pull x86 fixes from Ingo Molnar:
"The biggest part is a series of reverts for the macro based GCC
inlining workarounds. It caused regressions in distro build and other
kernel tooling environments, and the GCC project was very receptive to
fixing the underlying inliner weaknesses - so as time ran out we
decided to do a reasonably straightforward revert of the patches. The
plan is to rely on the 'asm inline' GCC 9 feature, which might be
backported to GCC 8 and could thus become reasonably widely available
on modern distros.
Other than those reverts, there's misc fixes from all around the
place.
I wish our final x86 pull request for v4.20 was smaller..."
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "kbuild/Makefile: Prepare for using macros in inline assembly code to work around asm() related GCC inlining bugs"
Revert "x86/objtool: Use asm macros to work around GCC inlining bugs"
Revert "x86/refcount: Work around GCC inlining bug"
Revert "x86/alternatives: Macrofy lock prefixes to work around GCC inlining bugs"
Revert "x86/bug: Macrofy the BUG table section handling, to work around GCC inlining bugs"
Revert "x86/paravirt: Work around GCC inlining bugs when compiling paravirt ops"
Revert "x86/extable: Macrofy inline assembly code to work around GCC inlining bugs"
Revert "x86/cpufeature: Macrofy inline assembly code to work around GCC inlining bugs"
Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"
x86/mtrr: Don't copy uninitialized gentry fields back to userspace
x86/fsgsbase/64: Fix the base write helper functions
x86/mm/cpa: Fix cpa_flush_array() TLB invalidation
x86/vdso: Pass --eh-frame-hdr to the linker
x86/mm: Fix decoy address handling vs 32-bit builds
x86/intel_rdt: Ensure a CPU remains online for the region's pseudo-locking sequence
x86/dump_pagetables: Fix LDT remap address marker
x86/mm: Fix guard hole handling
For the same reason as commit 25896d073d ("x86/build: Fix compiler
support check for CONFIG_RETPOLINE"), you cannot put this $(error ...)
into the parse stage of the top Makefile.
Perhaps I'd propose a more sophisticated solution later, but this is
the best I can do for now.
Link: https://lkml.org/lkml/2017/12/25/211
Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Reported-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Reported-by: Qian Cai <cai@lca.pw>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Qian Cai <cai@lca.pw>
This flag is documented in the GCC 4.6 manual, and recognized by
Clang as well. Let's rip off the cc-option switch.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
-Wstrict-prototypes is added to KBUILD_CFLAGS first, then overridden
by -Werror=strict-prototypes later.
Let's add -Werror=strict-prototypes unconditionally because it is
supported by GCC 4.6, and also by Clang.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
This flag is documented in the GCC 4.6 manual, and recognized by
Clang as well. Let's rip off the cc-option switch.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
- Use conventional $(MAKE) $(asm-generic)=<dir> style
for directory descending
- Remove unneeded FORCE since "all" is a phony target
- Remove unneeded "_dummy :=" assignment
- Skip $(shell mkdir ...) when headers exist in the directory
- Misc cleanups
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
This adds the build infrastructure for checking DT binding schema
documents and validating dts files using the binding schema.
Check DT binding schema documents:
make dt_binding_check
Build dts files and check using DT binding schema:
make dtbs_check
Optionally, DT_SCHEMA_FILES can be passed in with a schema file(s) to
use for validation. This makes it easier to find and fix errors
generated by a specific schema.
Currently, the validation targets are separate from a normal build to
avoid a hard dependency on the external DT schema project and because
there are lots of warnings generated.
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: linux-doc@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-kbuild@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
When CONFIG_HEADERS_CHECK is enabled, the headers_check is executed
as a serialized task in the vmlinux recipe.
Make it independent of vmlinux so that parallel building can process
the headers_check and other build targets simultaneously.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Currently, fixdep writes dependencies to .*.tmp, which is renamed to
.*.cmd after everything succeeds. This is a very safe way to avoid
corrupted .*.cmd files. The if_changed_dep has carried this safety
mechanism since it was added in 2002.
If fixdep fails for some reasons or a user terminates the build while
fixdep is running, the incomplete output from the fixdep could be
troublesome.
This is my insight about some bad scenarios:
[1] If the compiler succeeds to generate *.o file, but fixdep fails
to write necessary dependencies to .*.cmd file, Make will miss
to rebuild the object when headers or CONFIG options are changed.
In this case, fixdep should not generate .*.cmd file at all so
that 'arg-check' will surely trigger the rebuild of the object.
[2] A partially constructed .*.cmd file may not be a syntactically
correct makefile. The next time Make runs, it would include it,
then fail to parse it. Once this happens, 'make clean' is be the
only way to fix it.
In fact, [1] is no longer a problem since commit 9c2af1c737 ("kbuild:
add .DELETE_ON_ERROR special target"). Make deletes a target file on
any failure in its recipe. Because fixdep is a part of the recipe of
*.o target, if it fails, the *.o is deleted anyway. However, I am a
bit worried about the slight possibility of [2].
So, here is a solution. Let fixdep directly write to a .*.cmd file,
but allow makefiles to include it only when its corresponding target
exists.
This effectively reverts commit 2982c95357 ("kbuild: remove redundant
$(wildcard ...) for cmd_files calculation"), and commit 00d78ab2ba
("kbuild: remove dead code in cmd_files calculation in top Makefile")
because now we must check the presence of targets.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Now that 'archprepare' depends on 'scripts', Kbuild can descend into
scripts/gcc-plugins in a more standard way.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Before start descending, Kbuild needs to run 'prepare' and 'scripts',
which has been orthogonal to each other.
Going forward, let's consider 'scripts' is a part of the preparation.
This will allow more cleanups.
Move 'scripts' to the prerequisite of 'archprepare', where UML starts
compiling target *.c files.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
I am eagar to build under the scripts/ directory only with $(HOSTCC),
but scripts/mod/ highly depends on the $(CC) and target arch headers.
That it why the 'scripts' target must depend on 'asm-generic',
'gcc-plugins', and $(autoksyms_h).
Move it to the 'prepare0' stage. I know this is a cheesy workaround,
but better than the current situation.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Building a single target in an external module fails due to missing
.tmp_versions directory.
For example,
$ make -C /lib/modules/$(uname -r)/build M=$PWD foo.o
will fail in the following way:
CC [M] /home/masahiro/foo/foo.o
/bin/sh: 1: cannot create /home/masahiro/foo/.tmp_versions/foo.mod: Directory nonexistent
This is because $(cmd_crmodverdir) is executed only before building
/, %/, %.ko single targets of external modules. Create .tmp_versions
in the 'prepare' target.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
SUBDIRS has been kept as a backward compatibility since
commit ("[PATCH] kbuild: external module support") in 2002.
We do not need multiple ways to do the same thing, so I will remove
SUBDIRS after the Linux 5.3 release. I cleaned up in-tree code, and
updated the document so that nobody would try to use it.
Meanwhile, display the following warning if SUBDIRS is used.
Makefile:189: ================= WARNING ================
Makefile:190: 'SUBDIRS' will be removed after Linux 5.3
Makefile:191: Please use 'M=' or 'KBUILD_EXTMOD' instead
Makefile:192: ==========================================
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Boris Brezillon <boris.brezillon@bootlin.com> # for scx200_docflash.c
Acked-by: Guenter Roeck <linux@roeck-us.net> # for scx200_wdt.c
The powerpc makefile will use these in it's boot wrapper.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Collect basic Clang options such as --target, --prefix, --gcc-toolchain,
-no-integrated-as into a single variable CLANG_FLAGS so that it can be
easily reused in other parts of Makefile.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Greg Hackmann <ghackmann@google.com>
We are still a way off the Clang's integrated assembler support for
the kernel. Hence, -no-integrated-as is mandatory to build the kernel
with Clang. If you had an ancient version of Clang that does not
recognize this option, you would not be able to compile the kernel
anyway.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
There is one more user of $(cc-name) in the top Makefile. It is supposed
to detect Clang before invoking Kconfig, so it should still be there
in the $(shell ...) form. All the other users of $(cc-name) have been
replaced with $(CONFIG_CC_IS_CLANG). Hence, scripts/Kbuild.include does
not need to define cc-name any more.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Evaluating cc-name invokes the compiler every time even when you are
not compiling anything, like 'make help'. This is not efficient.
The compiler type has been already detected in the Kconfig stage.
Use CONFIG_CC_IS_CLANG, instead.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Paul Burton <paul.burton@mips.com> (MIPS)
Acked-by: Joel Stanley <joel@jms.id.au>
- Remove unused fallback for BUILD_BUG_ON (which technically contains a VLA)
- Lift -Wvla to the top-level Makefile
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Merge tag 'vla-v4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull VLA removal from Kees Cook:
"Globally warn on VLA use.
This turns on "-Wvla" globally now that the last few trees with their
VLA removals have landed (crypto, block, net, and powerpc).
Arnd mentioned that there may be a couple more VLAs hiding in
hard-to-find randconfigs, but nothing big has shaken out in the last
month or so in linux-next.
We should be basically VLA-free now! Wheee. :)
Summary:
- Remove unused fallback for BUILD_BUG_ON (which technically contains
a VLA)
- Lift -Wvla to the top-level Makefile"
* tag 'vla-v4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
Makefile: Globally enable VLA warning
compiler.h: give up __compiletime_assert_fallback()
- optimize kallsyms slightly
- remove check for old CFLAGS usage
- add some compiler flags unconditionally instead of evaluating
$(call cc-option,...)
- fix variable shadowing in host tools
- refactor scripts/mkmakefile
- refactor various makefiles
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Merge tag 'kbuild-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- optimize kallsyms slightly
- remove check for old CFLAGS usage
- add some compiler flags unconditionally instead of evaluating
$(call cc-option,...)
- fix variable shadowing in host tools
- refactor scripts/mkmakefile
- refactor various makefiles
* tag 'kbuild-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
modpost: Create macro to avoid variable shadowing
ASN.1: Remove unnecessary shadowed local variable
kbuild: use 'else ifeq' for checksrc to improve readability
kbuild: remove unneeded link_multi_deps
kbuild: add -Wno-unused-but-set-variable flag unconditionally
kbuild: add -Wdeclaration-after-statement flag unconditionally
kbuild: add -Wno-pointer-sign flag unconditionally
modpost: remove leftover symbol prefix handling for module device table
kbuild: simplify command line creation in scripts/mkmakefile
kbuild: do not pass $(objtree) to scripts/mkmakefile
kbuild: remove user ID check in scripts/mkmakefile
kbuild: remove VERSION and PATCHLEVEL from $(objtree)/Makefile
kbuild: add --include-dir flag only for out-of-tree build
kbuild: remove dead code in cmd_files calculation in top Makefile
kbuild: hide most of targets when running config or mixed targets
kbuild: remove old check for CFLAGS use
kbuild: prefix Makefile.dtbinst path with $(srctree) unconditionally
kallsyms: remove left-over Blackfin code
kallsyms: reduce size a little on 64-bit
- Sync dtc with upstream version v1.4.7-14-gc86da84d30e4
- Work to get rid of direct accesses to struct device_node name and
type pointers in preparation for removing them. New helpers for
parsing DT cpu nodes and conversions to use the helpers. printk
conversions to %pOFn for printing DT node names. Most went thru
subystem trees, so this is the remainder.
- Fixes to DT child node lookups to actually be restricted to child
nodes instead of treewide.
- Refactoring of dtb targets out of arch code. This makes the support
more uniform and enables building all dtbs on c6x, microblaze, and
powerpc.
- Various DT binding updates for Renesas r8a7744 SoC
- Vendor prefixes for Facebook, OLPC
- Restructuring of some ARM binding docs moving some peripheral bindings
out of board/SoC binding files
- New "secure-chosen" binding for secure world settings on ARM
- Dual licensing of 2 DT IRQ binding headers
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Merge tag 'devicetree-for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull Devicetree updates from Rob Herring:
"A bit bigger than normal as I've been busy this cycle.
There's a few things with dependencies and a few things subsystem
maintainers didn't pick up, so I'm taking them thru my tree.
The fixes from Johan didn't get into linux-next, but they've been
waiting for some time now and they are what's left of what subsystem
maintainers didn't pick up.
Summary:
- Sync dtc with upstream version v1.4.7-14-gc86da84d30e4
- Work to get rid of direct accesses to struct device_node name and
type pointers in preparation for removing them. New helpers for
parsing DT cpu nodes and conversions to use the helpers. printk
conversions to %pOFn for printing DT node names. Most went thru
subystem trees, so this is the remainder.
- Fixes to DT child node lookups to actually be restricted to child
nodes instead of treewide.
- Refactoring of dtb targets out of arch code. This makes the support
more uniform and enables building all dtbs on c6x, microblaze, and
powerpc.
- Various DT binding updates for Renesas r8a7744 SoC
- Vendor prefixes for Facebook, OLPC
- Restructuring of some ARM binding docs moving some peripheral
bindings out of board/SoC binding files
- New "secure-chosen" binding for secure world settings on ARM
- Dual licensing of 2 DT IRQ binding headers"
* tag 'devicetree-for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (78 commits)
ARM: dt: relicense two DT binding IRQ headers
power: supply: twl4030-charger: fix OF sibling-node lookup
NFC: nfcmrvl_uart: fix OF child-node lookup
net: stmmac: dwmac-sun8i: fix OF child-node lookup
net: bcmgenet: fix OF child-node lookup
drm/msm: fix OF child-node lookup
drm/mediatek: fix OF sibling-node lookup
of: Add missing exports of node name compare functions
dt-bindings: Add OLPC vendor prefix
dt-bindings: misc: bk4: Add device tree binding for Liebherr's BK4 SPI bus
dt-bindings: thermal: samsung: Add SPDX license identifier
dt-bindings: clock: samsung: Add SPDX license identifiers
dt-bindings: timer: ostm: Add R7S9210 support
dt-bindings: phy: rcar-gen2: Add r8a7744 support
dt-bindings: can: rcar_can: Add r8a7744 support
dt-bindings: timer: renesas, cmt: Document r8a7744 CMT support
dt-bindings: watchdog: renesas-wdt: Document r8a7744 support
dt-bindings: thermal: rcar: Add device tree support for r8a7744
Documentation: dt: Add binding for /secure-chosen/stdout-path
dt-bindings: arm: zte: Move sysctrl bindings to their own doc
...
Pull locking and misc x86 updates from Ingo Molnar:
"Lots of changes in this cycle - in part because locking/core attracted
a number of related x86 low level work which was easier to handle in a
single tree:
- Linux Kernel Memory Consistency Model updates (Alan Stern, Paul E.
McKenney, Andrea Parri)
- lockdep scalability improvements and micro-optimizations (Waiman
Long)
- rwsem improvements (Waiman Long)
- spinlock micro-optimization (Matthew Wilcox)
- qspinlocks: Provide a liveness guarantee (more fairness) on x86.
(Peter Zijlstra)
- Add support for relative references in jump tables on arm64, x86
and s390 to optimize jump labels (Ard Biesheuvel, Heiko Carstens)
- Be a lot less permissive on weird (kernel address) uaccess faults
on x86: BUG() when uaccess helpers fault on kernel addresses (Jann
Horn)
- macrofy x86 asm statements to un-confuse the GCC inliner. (Nadav
Amit)
- ... and a handful of other smaller changes as well"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits)
locking/lockdep: Make global debug_locks* variables read-mostly
locking/lockdep: Fix debug_locks off performance problem
locking/pvqspinlock: Extend node size when pvqspinlock is configured
locking/qspinlock_stat: Count instances of nested lock slowpaths
locking/qspinlock, x86: Provide liveness guarantee
x86/asm: 'Simplify' GEN_*_RMWcc() macros
locking/qspinlock: Rework some comments
locking/qspinlock: Re-order code
locking/lockdep: Remove duplicated 'lock_class_ops' percpu array
x86/defconfig: Enable CONFIG_USB_XHCI_HCD=y
futex: Replace spin_is_locked() with lockdep
locking/lockdep: Make class->ops a percpu counter and move it under CONFIG_DEBUG_LOCKDEP=y
x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs
x86/cpufeature: Macrofy inline assembly code to work around GCC inlining bugs
x86/extable: Macrofy inline assembly code to work around GCC inlining bugs
x86/paravirt: Work around GCC inlining bugs when compiling paravirt ops
x86/bug: Macrofy the BUG table section handling, to work around GCC inlining bugs
x86/alternatives: Macrofy lock prefixes to work around GCC inlining bugs
x86/refcount: Work around GCC inlining bug
x86/objtool: Use asm macros to work around GCC inlining bugs
...
We have raised the compiler requirement from time to time.
With commit cafa0010cd ("Raise the minimum required gcc version
to 4.6"), the minimum for GCC is 4.6 now.
This flag was added by GCC 4.6, and it is recognized by ICC as well.
It is true that Clang does not support this flag but this commit is
just touching the else part of the "ifeq ($(cc-name),clang)" check.
Hence, Clang build is not affected.
Let's rip off the cc-disable-warning switch, and see if somebody
complains about it.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
We have raised the compiler requirement from time to time.
With commit cafa0010cd ("Raise the minimum required gcc version
to 4.6"), the minimum for GCC is 4.6 now.
This flag has been here since the pre-git era. It is documented in
the GCC 4.6 manual, and it is recognized by Clang and ICC as well.
Let's rip off the cc-option switch, and see if somebody complains
about it.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
We have raised the compiler requirement from time to time.
With commit cafa0010cd ("Raise the minimum required gcc version
to 4.6"), the minimum for GCC is 4.6 now.
The -Wno-pointer-sign has been here since the pre-git era. It is
documented in the GCC 4.6 manual, and it is recognized by Clang
and ICC as well.
Let's rip off the cc-disable-warning switch, and see if somebody
complains about it.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
- Fix warnings from recordmcount.pl when building with Clang
- Allow Clang to use GNU toolchains correctly
- Disable CONFIG_SAMPLES for UML to avoid build error
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Merge tag 'kbuild-fixes-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Masahiro writes:
"Kbuild fixes for v4.19 (2nd)
- Fix warnings from recordmcount.pl when building with Clang
- Allow Clang to use GNU toolchains correctly
- Disable CONFIG_SAMPLES for UML to avoid build error"
* tag 'kbuild-fixes-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
samples: disable CONFIG_SAMPLES for UML
kbuild: allow to use GCC toolchain not in Clang search path
ftrace: Build with CPPFLAGS to get -Qunused-arguments
Since $(objtree) is always '.', it is not useful to pass it to
scripts/mkmakefile. I assume nobody wants to run this script directly.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The --include-dir flag is used to include check-in Makefiles from
$(objtree) without $(srctree)/ prefix. Obviously, this is unneeded
for in-tree build. Add the flag just before changing the working
directory.
This becomes effective after invoking sub-make. Add a little bit
comments about it.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Using macros in inline assembly allows us to work around bugs
in GCC's inlining decisions.
Compile macros.S and use it to assemble all C files.
Currently only x86 will use it.
Background:
The inlining pass of GCC doesn't include an assembler, so it's not aware
of basic properties of the generated code, such as its size in bytes,
or that there are such things as discontiuous blocks of code and data
due to the newfangled linker feature called 'sections' ...
Instead GCC uses a lazy and fragile heuristic: it does a linear count of
certain syntactic and whitespace elements in inlined assembly block source
code, such as a count of new-lines and semicolons (!), as a poor substitute
for "code size and complexity".
Unsurprisingly this heuristic falls over and breaks its neck whith certain
common types of kernel code that use inline assembly, such as the frequent
practice of putting useful information into alternative sections.
As a result of this fresh, 20+ years old GCC bug, GCC's inlining decisions
are effectively disabled for inlined functions that make use of such asm()
blocks, because GCC thinks those sections of code are "large" - when in
reality they are often result in just a very low number of machine
instructions.
This absolute lack of inlining provess when GCC comes across such asm()
blocks both increases generated kernel code size and causes performance
overhead, which is particularly noticeable on paravirt kernels, which make
frequent use of these inlining facilities in attempt to stay out of the
way when running on baremetal hardware.
Instead of fixing the compiler we use a workaround: we set an assembly macro
and call it from the inlined assembly block. As a result GCC considers the
inline assembly block as a single instruction. (Which it often isn't but I digress.)
This uglifies and bloats the source code - for example just the refcount
related changes have this impact:
Makefile | 9 +++++++--
arch/x86/Makefile | 7 +++++++
arch/x86/kernel/macros.S | 7 +++++++
scripts/Kbuild.include | 4 +++-
scripts/mod/Makefile | 2 ++
5 files changed, 26 insertions(+), 3 deletions(-)
Yay readability and maintainability, it's not like assembly code is hard to read
and maintain ...
We also hope that GCC will eventually get fixed, but we are not holding
our breath for that. Yet we are optimistic, it might still happen, any decade now.
[ mingo: Wrote new changelog describing the background. ]
Tested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Nadav Amit <namit@vmware.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kbuild@vger.kernel.org
Link: http://lkml.kernel.org/r/20181003213100.189959-3-namit@vmware.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There is nothing arch specific about building dtb files other than their
location under /arch/*/boot/dts/. Keeping each arch aligned is a pain.
The dependencies and supported targets are all slightly different.
Also, a cross-compiler for each arch is needed, but really the host
compiler preprocessor is perfectly fine for building dtbs. Move the
build rules to a common location and remove the arch specific ones. This
is done in a single step to avoid warnings about overriding rules.
The build dependencies had been a mixture of 'scripts' and/or 'prepare'.
These pull in several dependencies some of which need a target compiler
(specifically devicetable-offsets.h) and aren't needed to build dtbs.
All that is really needed is dtc, so adjust the dependencies to only be
dtc.
This change enables support 'dtbs_install' on some arches which were
missing the target.
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Paul Burton <paul.burton@mips.com>
Acked-by: Ley Foon Tan <ley.foon.tan@intel.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-kbuild@vger.kernel.org
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: uclinux-h8-devel@lists.sourceforge.jp
Cc: linux-mips@linux-mips.org
Cc: nios2-dev@lists.rocketboards.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-xtensa@linux-xtensa.org
Signed-off-by: Rob Herring <robh@kernel.org>
When using a GCC cross toolchain which is not in a compiled in
Clang search path, Clang reverts to the system assembler and
linker. This leads to assembler or linker errors, depending on
which tool is first used for a given architecture.
It seems that Clang is not searching $PATH for a matching
assembler or linker.
Make sure that Clang picks up the correct assembler or linker by
passing the cross compilers bin directory as search path.
This allows to use Clang provided by distributions with GCC
toolchains not in /usr/bin.
Link: https://github.com/ClangBuiltLinux/linux/issues/78
Signed-off-by: Stefan Agner <stefan@agner.ch>
Reviewed-and-tested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Masahiro Yamada