- fix warnings of host programs
- fix "make tags" when COMPILE_SOURCE=1 is specified along with O=
- clarify help message of C=1 option
- fix dependency for ncurses compatibility check
- fix "make headers_install" for fakechroot environment
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Merge tag 'kbuild-fixes-v4.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:
"Nothing scary, just some random fixes:
- fix warnings of host programs
- fix "make tags" when COMPILED_SOURCE=1 is specified along with O=
- clarify help message of C=1 option
- fix dependency for ncurses compatibility check
- fix "make headers_install" for fakechroot environment"
* tag 'kbuild-fixes-v4.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kconfig: fix sparse warnings in nconfig
kbuild: fix header installation under fakechroot environment
kconfig: Check for libncurses before menuconfig
Kbuild: tiny correction on `make help`
tags: honor COMPILED_SOURCE with apart output directory
genksyms: add printf format attribute to error_with_pos()
There were a few bits and pieces left over from the now-disused DocBook
toolchain; git rid of them.
Reported-by: Markus Heiser <markus.heiser@darmarit.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
clang generates plenty of these warnings in different parts of the code,
to an extent that the warnings are little more than noise. Disable the
'address-of-packed-member' warning.
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Commit 90ac086bca ("Makefile: include arch/*/include/generated/uapi
before .../generated") introduced this for bisect'ability. The commit
chose to promote arch/*/include/generated/uapi in the search path
rather than cleaning stale headers.
After all, we found that approach was not enough, and ended up with
cleaning stale headers by commit cda2c65f98 ("kbuild: Remove stale
asm-generic wrappers").
So, the extra search path is no longer needed because Kbuild invokes
scripts/Makefile.asm-generic and remove stale headers before it starts
descending.
This commit is also reverting commit dc33db7c33 ("Kbuild: avoid
duplicate include path") because we have no more duplicated path.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The help info of `make C=1` is little confusing, make it clear.
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
This allows to detect -s (--silent) option without checking GNU Make
version.
As commit e36aaea289 ("kbuild: Fix silent builds with make-4")
pointed out, GNU Make 4.x changed the way/order it presents the
command line options into MAKEFLAGS.
In Make 3.8x, 's' is always the first in a group of short options.
The group may be prefixed with '-' in some cases.
In Make 4.x, 's' is always the last in a group of short options.
As commit e6ac89fabd ("kbuild: Correctly deal with make options
which contain an 's'") addressed, we also need to deal with long
options that contain 's', like --warn-undefined-variables.
Test cases:
[1] command line input: make --silent
-> MAKEFLAGS for Make 3.8x: s
-> MAKEFLAGS for Make 4.x : s
[2] command line input: make -srR
-> MAKEFLAGS for Make 3.8x: sRr
-> MAKEFLAGS for Make 4.x : rRs
[3] command line input: make -s -rR --warn-undefined-variables
-> MAKEFLAGS for Make 3.8x: --warn-undefined-variables -sRr
-> MAKEFLAGS for Make 4.x : rRs --warn-undefined-variables
My idea to cater to all the cases more easily is to filter out long
options (--%), then search 's' with $(findstring ...). This way will
be more future-proof even if future versions of Make put 's' in the
middle of the group.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Mauro says:
This patch series convert the remaining DocBooks to ReST.
The first version was originally
send as 3 patch series:
[PATCH 00/36] Convert DocBook documents to ReST
[PATCH 0/5] Convert more books to ReST
[PATCH 00/13] Get rid of DocBook
The lsm book was added as if it were a text file under
Documentation. The plan is to merge it with another file
under Documentation/security, after both this series and
a security Documentation patch series gets merged.
It also adjusts some Sphinx-pedantic errors/warnings on
some kernel-doc markups.
I also added some patches here to add PDF output for all
existing ReST books.
Since commit 61562f981e ("uapi: export all arch specifics
directories"), "make INSTALL_HDR_PATH=$root/usr headers_install"
deletes standard glibc headers and others in $(root)/usr/include.
The cause of the issue is that headers_install now starts descending
from arch/$(hdr-arch)/include/uapi with $(root)/usr/include for its
destination when installing asm headers. So, headers already there
are assumed to be unwanted.
When headers_install starts descending from include/uapi with
$(root)/usr/include for its destination, it works around the problem
by creating an dummy destination $(root)/usr/include/uapi, but this
is tricky.
To fix the problem in a clean way is to skip headers install/check
in include/uapi and arch/$(hdr-arch)/include/uapi because we know
there are only sub-directories in uapi directories. A good side
effect is the empty destination $(root)/usr/include/uapi will go
away.
I am also removing the trailing slash in the headers_check target to
skip checking in arch/$(hdr-arch)/include/uapi.
Fixes: 61562f981e ("uapi: export all arch specifics directories")
Reported-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Improvement of headers_install by Nicolas Dichtel.
It has been long since the introduction of uapi directories,
but the de-coupling of exported headers has not been completed.
Headers listed in header-y are exported whether they exist in
uapi directories or not. His work fixes this inconsistency.
All (and only) headers under uapi directories are now exported.
The asm-generic wrappers are still exceptions, but this is a big
step forward.
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Merge tag 'kbuild-uapi-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild UAPI updates from Masahiro Yamada:
"Improvement of headers_install by Nicolas Dichtel.
It has been long since the introduction of uapi directories, but the
de-coupling of exported headers has not been completed. Headers listed
in header-y are exported whether they exist in uapi directories or
not. His work fixes this inconsistency.
All (and only) headers under uapi directories are now exported. The
asm-generic wrappers are still exceptions, but this is a big step
forward"
* tag 'kbuild-uapi-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
arch/include: remove empty Kbuild files
uapi: export all arch specifics directories
uapi: export all headers under uapi directories
smc_diag.h: fix include from userland
btrfs_tree.h: fix include from userland
uapi: includes linux/types.h before exporting files
Makefile.headersinst: remove destination-y option
Makefile.headersinst: cleanup input files
x86: stop exporting msr-index.h to userland
nios2: put setup.h in uapi
h8300: put bitsperlong.h in uapi
- Improve Clang support
- Clean up various Makefiles
- Improve build log visibility (objtool, alpha, ia64)
- Improve compiler flag evaluation for better build performance
- Fix GCC version-dependent warning
- Fix genksyms
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Merge tag 'kbuild-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- improve Clang support
- clean up various Makefiles
- improve build log visibility (objtool, alpha, ia64)
- improve compiler flag evaluation for better build performance
- fix GCC version-dependent warning
- fix genksyms
* tag 'kbuild-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (23 commits)
kbuild: dtbinst: remove unnecessary __dtbs_install_prep target
ia64: beatify build log for gate.so and gate-syms.o
alpha: make short build log available for division routines
alpha: merge build rules of division routines
alpha: add $(src)/ rather than $(obj)/ to make source file path
Makefile: evaluate LDFLAGS_BUILD_ID only once
objtool: make it visible in make V=1 output
kbuild: clang: add -no-integrated-as to KBUILD_[AC]FLAGS
kbuild: Add support to generate LLVM assembly files
kbuild: Add better clang cross build support
kbuild: drop -Wno-unknown-warning-option from clang options
kbuild: fix asm-offset generation to work with clang
kbuild: consolidate redundant sed script ASM offset generation
frv: Use OFFSET macro in DEF_*REG()
kbuild: avoid conflict between -ffunction-sections and -pg on gcc-4.7
kbuild: Consolidate header generation from ASM offset information
kbuild: use -Oz instead of -Os when using clang
kbuild, LLVMLinux: Add -Werror to cc-option to support clang
Kbuild: make designated_init attribute fatal
kbuild: drop unneeded patterns '.*.orig' and '.*.rej' from distclean
...
This patch removes the need of subdir-y. Now all files/directories under
arch/<arch>/include/uapi/ are exported.
The only change for userland is the layout of the command 'make
headers_install_all': directories asm-<arch> are replaced by arch-<arch>/.
Those new directories contains all files/directories of the specified arch.
Note that only cris and tile have more directories than only asm:
- arch-v[10|32] for cris;
- arch for tile.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Add a top-level Makefile help target for Userspace tools.
Also make each help "heading" end with a colon ':'.
Link: http://lkml.kernel.org/r/55c986ff-3966-3e47-2984-7349da2cce51@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Evaluate LDFLAGS_BUILD_ID (which involves invoking the compiler) only
once instead of over and over.
This provides a ~20% reduction in null build time with x86 allnoconfig:
$ make allnoconfig && make -j8
$ perf stat -r5 -e sched:sched_process_exec make -j8
- 2 119 sched:sched_process_exec
+ 1 878 sched:sched_process_exec
- 1,238817018 seconds time elapsed
+ 0,971020553 seconds time elapsed
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
guide for user-space API documents, rather sparsely populated at the
moment, but it's a start. Markus improved the infrastructure for
converting diagrams. Mauro has converted much of the USB documentation
over to RST. Plus the usual set of fixes, improvements, and tweaks.
There's a bit more than the usual amount of reaching out of Documentation/
to fix comments elsewhere in the tree; I have acks for those where I could
get them.
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Merge tag 'docs-4.12' of git://git.lwn.net/linux
Pull documentation update from Jonathan Corbet:
"A reasonably busy cycle for documentation this time around. There is a
new guide for user-space API documents, rather sparsely populated at
the moment, but it's a start. Markus improved the infrastructure for
converting diagrams. Mauro has converted much of the USB documentation
over to RST. Plus the usual set of fixes, improvements, and tweaks.
There's a bit more than the usual amount of reaching out of
Documentation/ to fix comments elsewhere in the tree; I have acks for
those where I could get them"
* tag 'docs-4.12' of git://git.lwn.net/linux: (74 commits)
docs: Fix a couple typos
docs: Fix a spelling error in vfio-mediated-device.txt
docs: Fix a spelling error in ioctl-number.txt
MAINTAINERS: update file entry for HSI subsystem
Documentation: allow installing man pages to a user defined directory
Doc/PM: Sync with intel_powerclamp code behavior
zr364xx.rst: usb/devices is now at /sys/kernel/debug/
usb.rst: move documentation from proc_usb_info.txt to USB ReST book
convert philips.txt to ReST and add to media docs
docs-rst: usb: update old usbfs-related documentation
arm: Documentation: update a path name
docs: process/4.Coding.rst: Fix a couple of document refs
docs-rst: fix usb cross-references
usb: gadget.h: be consistent at kernel doc macros
usb: composite.h: fix two warnings when building docs
usb: get rid of some ReST doc build errors
usb.rst: get rid of some Sphinx errors
usb/URB.txt: convert to ReST and update it
usb/persist.txt: convert to ReST and add to driver-api book
usb/hotplug.txt: convert to ReST and add to driver-api book
...
The Linux Kernel relies on GCC's acceptance of inline assembly as an
opaque object which will not have any validation performed on the content.
The current behaviour in LLVM is to perform validation of the contents by
means of parsing the input if the MC layer can handle it.
Disable clangs integrated assembler and use the GNU assembler instead.
Wording-mostly-from: Saleem Abdulrasool <compnerd@compnerd.org>
Signed-off-by: Michael Davidson <md@google.com>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Add rules to kbuild in order to generate LLVM assembly files with the .ll
extension when using clang.
# from c code
make CC=clang kernel/pid.ll
Signed-off-by: Vinícius Tinti <viniciustinti@gmail.com>
Signed-off-by: Behan Webster <behanw@converseincode.com>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Add cross target to CC if using clang. Also add custom gcc toolchain
path for fallback gcc tools.
Clang will fallback to using things like ld, as, and libgcc if
(respectively) one of the llvm linkers isn't available, the integrated
assembler is turned off, or an appropriately cross-compiled version of
compiler-rt isn't available. To this end, you can specify the path to
this fallback gcc toolchain with GCC_TOOLCHAIN.
Signed-off-by: Behan Webster <behanw@converseincode.com>
Reviewed-by: Jan-Simon Möller <dl9pf@gmx.de>
Reviewed-by: Mark Charlebois <charlebm@gmail.com>
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Since commit c3f0d0bc5b ("kbuild, LLVMLinux: Add -Werror to
cc-option to support clang"), cc-option and friends work nicely
for clang.
However, -Wno-unknown-warning-option makes clang happy with any
unknown warning options even if -Werror is specified.
Once -Wno-unknown-warning-option is added, any succeeding call of
cc-disable-warning is evaluated positive, then unknown warning
options are accepted. This should be dropped.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Arnd Bergmann reported:
"When ftrace is enabled and we build with gcc-4.7 or older, we
get a warning for each file on architectures that select
CONFIG_LD_DEAD_CODE_DATA_ELIMINATION:
warning: -ffunction-sections disabled; it makes profiling impossible [enabled by default]
"
Since commit c3f0d0bc5b ("kbuild, LLVMLinux: Add -Werror to
cc-option to support clang"), warnings are treated as errors in
cc-option checks. CC_FLAGS_FTRACE is blindly added to KBUILD_CFLAGS,
so $(call cc-option,-ffunction-sections,) should be moved below it
in order to detect the conflict between the two options.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
- Hand-off primary maintainership of Kbuild
- Fix build warnings
- Fix build error when GCOV is enabled with old compiler
- Fix HAVE_ASM_GOTO check when GCC plugin is enabled
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Merge tag 'kbuild-fixes-v4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:
- hand-off primary maintainership of Kbuild
- fix build warnings
- fix build error when GCOV is enabled with old compiler
- fix HAVE_ASM_GOTO check when GCC plugin is enabled
* tag 'kbuild-fixes-v4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
gconfig: remove misleading parentheses around a condition
jump label: fix passing kbuild_cflags when checking for asm goto support
Kbuild: use cc-disable-warning consistently for maybe-uninitialized
kbuild: external module build warnings when KBUILD_OUTPUT set and W=1
MAINTAINERS: add Masahiro Yamada as a Kbuild maintainer
Documentation/sparse.txt has been moved to
Documentation/dev-tools/sparse.rst
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
If a structure is marked with __attribute__((designated_init)) from
GCC or Sparse, it needs to have all static initializers using designated
initialization. Fail the build for any missing cases. This attribute will
be used by the randstruct plugin to make sure randomized structures are
being correctly initialized.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The latest change of asm goto support check added passing of KBUILD_CFLAGS
to compiler. When these flags reference gcc plugins that are not built yet,
the check fails.
When one runs "make bzImage" followed by "make modules", the kernel is always
built with HAVE_JUMP_LABEL disabled, while the modules are built depending on
CONFIG_JUMP_LABEL. If HAVE_JUMP_LABEL macro happens to be different, modules
are built with undefined references, e.g.:
ERROR: "static_key_slow_inc" [net/netfilter/xt_TEE.ko] undefined!
ERROR: "static_key_slow_dec" [net/netfilter/xt_TEE.ko] undefined!
ERROR: "static_key_slow_dec" [net/netfilter/nft_meta.ko] undefined!
ERROR: "static_key_slow_inc" [net/netfilter/nft_meta.ko] undefined!
ERROR: "nf_hooks_needed" [net/netfilter/ipvs/ip_vs.ko] undefined!
ERROR: "nf_hooks_needed" [net/ipv6/ipv6.ko] undefined!
ERROR: "static_key_count" [net/ipv6/ipv6.ko] undefined!
ERROR: "static_key_slow_inc" [net/ipv6/ipv6.ko] undefined!
This change moves the check before all these references are added
to KBUILD_CFLAGS. This is correct because subsequent KBUILD_CFLAGS
modifications are not relevant to this check.
Reported-by: Anton V. Boyarshinov <boyarsh@altlinux.org>
Fixes: 35f860f9ba ("jump label: pass kbuild_cflags when checking for asm goto support")
Cc: stable@vger.kernel.org # v4.10
Signed-off-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: David Lin <dtwlin@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
In commit a76bcf557e ("Kbuild: enable -Wmaybe-uninitialized warning
for "make W=1""), I reverted another change that happened to fix a problem
with old compilers, and now we get this report again with old compilers
(prior to gcc-4.8) and GCOV enabled:
cc1: warnings being treated as errors
drivers/gpu/drm/i915/intel_ringbuffer.c: In function 'intel_ring_setup_status_page':
drivers/gpu/drm/i915/intel_ringbuffer.c:438: error: 'mmio.reg' may be used uninitialized in this function
At top level:
>> cc1: error: unrecognized command line option "-Wno-maybe-uninitialized"
The problem is that we turn off the warning conditionally in a number
of places as we should, but one of them does it unconditionally.
Instead, change it to call cc-disable-warning as we do elsewhere.
The original patch that caused it was merged into linux-4.7, then
4.8 removed the change and 4.9 brought it back, so we probably want
a backport to 4.9 once this is merged.
Use a ':=' assignment instead of '=' to force the cc-disable-warning
call to only be evaluated once instead of every time.
Cc: stable@vger.kernel.org
Fixes: a76bcf557e ("Kbuild: enable -Wmaybe-uninitialized warning for "make W=1"")
Fixes: e72e2dfe7c ("gcov: disable -Wmaybe-uninitialized warning")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The patterns '.*.orig' and '.*.rej' are cleaned away by '*.orig' and
'*.rej' seen two lines above.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Extra gcc checks like W=1 were moved to scripts/Makefile.exrawarn,
so the file name in comment needs to be fixed.
Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Pull objtool fixes from Ingo Molnar:
"A handful of objtool fixes related to unreachable code, plus a build
fix for out of tree modules"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool: Enclose contents of unreachable() macro in a block
objtool: Prevent GCC from merging annotate_unreachable()
objtool: Improve detection of BUG() and other dead ends
objtool: Fix CONFIG_STACK_VALIDATION=y warning for out-of-tree modules
Three more DocBook template files have been converted to RST; only 21 to
go. There are various build improvements and the usual array of
documentation improvements and fixes.
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Merge tag 'docs-4.11' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"A slightly quieter cycle for documentation this time around.
Three more DocBook template files have been converted to RST; only 21
to go. There are various build improvements and the usual array of
documentation improvements and fixes"
* tag 'docs-4.11' of git://git.lwn.net/linux: (44 commits)
docs / driver-api: Fix structure references in device_link.rst
PM / docs: Fix structure references in device.rst
Add a target to check broken external links in the Documentation
Documentation: Fix linux-api list typo
Documentation: DocBook/Makefile comment typo
Improve sparse documentation
Documentation: make Makefile.sphinx no-ops quieter
Documentation: DMA-ISA-LPC.txt
Documentation: input: fix path to input code definitions
docs: Remove the copyright year from conf.py
docs: Fix a warning in the Korean HOWTO.rst translation
PM / sleep / docs: Convert PM notifiers document to reST
PM / core / docs: Convert sleep states API document to reST
PM / core: Update kerneldoc comments in pm.h
doc-rst: Fix recursive make invocation from macros
doc-rst: Delete output of failed dot-SVG conversion
doc-rst: Break shell command sequences on failure
Documentation/sphinx: make targets independent of Sphinx work for HAVE_SPHINX=0
doc-rst: fixed cleandoc target when used with O=dir
Documentation/sphinx: prevent generation of .pyc files in the source tree
...
Pull perf updates from Ingo Molnar:
"On the kernel side the main changes in this cycle were:
- Add Intel Kaby Lake CPU support (Srinivas Pandruvada)
- AMD uncore driver updates for fam17 (Janakarajan Natarajan)
- Intel/PT updates and core events optimizations and cleanups
(Alexander Shishkin)
- cgroups events fixes (David Carrillo-Cisneros)
- kprobes improvements (Masami Hiramatsu)
- ... plus misc fixes and updates.
On the tooling side the main changes were:
- Support clang build in tools/{perf,lib/{bpf,traceevent,api}} with
CC=clang, to, for instance, take advantage of better warnings
(Arnaldo Carvalho de Melo):
- Introduce the 'delta-abs' 'perf diff' compute method, that orders
the histogram entries by the absolute value of the percentage delta
for a function in two perf.data files, i.e. the functions that
changed the most (increase or decrease in samples) comes first
(Namhyung Kim)
- Add support for parsing Intel uncore vendor event files and add
uncore vendor events for the Intel server processors (Haswell,
Broadwell, IvyBridge), Xeon Phi (Knights Landing) and Broadwell DE
(Andi Kleen)
- Introduce 'perf ftrace' a perf front end to the kernel's ftrace
function and function_graph tracer, defaulting to the
"function_graph" tracer, more work will be done in reviving this
effort, forward porting it from its initial patch submission
(Namhyung Kim)
- Add 'e' and 'c' hotkeys to expand/collapse call chains for a single
hist entry in the 'perf report' and 'perf top' TUI (Jiri Olsa)
- Account thread wait time (off CPU time) separately: sleep, iowait
and preempt, based on the prev_state of the last event, show the
breakdown when using "perf sched timehist --state" (Namhyumg Kim)
- Add more triggers to switch the output file (perf.data.TIMESTAMP).
Now, in addition to switching to a different output file when
receiving a SIGUSR2, one can also specify file size and time based
triggers:
perf record -a --switch-output=signal
is equivalent to what we had before:
perf record -a --switch-output
While we can also ask for the file to be "sliced" by size, taking
into account that that will happen only when we get woken up by the
kernel, i.e. one has to take into account the --mmap-pages (the
size of the perf mmap ring buffer):
perf record -a --switch-output=2G
will break the perf.data output into multiple files limited to 2GB
of samples, right when generating the output.
For time based samples, alert() will be used, so to have 1 minute
limited perf.data output files:
perf record -a --switch-output=1m
(Jiri Olsa)
- Improve 'perf trace' (Arnaldo Carvalho de Melo)
- 'perf kallsyms' toy tool to look for extended symbol information on
the running kernel and demonstrate the machine/thread/symbol APIs
for use in other tools, such as 'perf probe' (Arnaldo Carvalho de
Melo)
- ... plus tons of other changes, see the shortlog and Git log for
details"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (131 commits)
perf tools: Add missing parse_events_error() prototype
perf pmu: Fix check for unset alias->unit array
perf tools: Be consistent on the type of map->symbols[] interator
perf intel pt decoder: clang has no -Wno-override-init
perf evsel: Do not put a variable sized type not at the end of a struct
perf probe: Avoid accessing uninitialized 'map' variable
perf tools: Do not put a variable sized type not at the end of a struct
perf record: Do not put a variable sized type not at the end of a struct
perf tests: Synthesize struct instead of using field after variable sized type
perf bench numa: Make sure dprintf() is not defined
Revert "perf bench futex: Sanitize numeric parameters"
tools lib subcmd: Make it an error to pass a signed value to OPTION_UINTEGER
tools: Set the maximum optimization level according to the compiler being used
tools: Suppress request for warning options not existent in clang
samples/bpf: Reset global variables
samples/bpf: Ignore already processed ELF sections
samples/bpf: Add missing header
perf symbols: dso->name is an array, no need to check it against NULL
perf tests record: No need to test an array against NULL
perf symbols: No need to check if sym->name is NULL
...
When building a CONFIG_STACK_VALIDATION enabled kernel without the
libelf devel package installed, the Makefile prints a warning:
"Cannot use CONFIG_STACK_VALIDATION, please install libelf-dev, libelf-devel or elfutils-libelf-devel"
But when building an out-of-tree module, the warning doesn't show.
Instead it tries to use objtool, and the build fails with:
/bin/sh: ./tools/objtool/objtool: No such file or directory
Make sure the warning and the disabling of objtool occur in all cases,
by moving the CONFIG_STACK_VALIDATION checks outside the 'ifeq
($(KBUILD_EXTMOD),)' block in the Makefile.
Tested-By: Marc MERLIN <marc@merlins.org>
Suggested-by: Jessica Yu <jeyu@redhat.com>
Reported-by: Marc MERLIN <marc@merlins.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Jessica Yu <jeyu@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 3b27a0c85d ("objtool: Detect and warn if libelf is missing and don't break the build")
Link: http://lkml.kernel.org/r/b3088ae4a8698143d4851965793c61fec2135b1f.1487182864.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Documentation shouldn't have broken links.
sphinx linkcheck builder scans all documents for external links, tries
to open them with urllib2, and writes an overview which ones are broken
and redirected to standard output and to output.txt in the output
directory.
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Rémy Léone <remy.leone@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Some versions of ARM GCC compiler such as Android toolchain throws in a
'-fpic' flag by default. This causes the gcc-goto check script to fail
although some config would have '-fno-pic' flag in the KBUILD_CFLAGS.
This patch passes the KBUILD_CFLAGS to the check script so that the
script does not rely on the default config from different compilers.
Link: http://lkml.kernel.org/r/20170120234329.78868-1-dtwlin@google.com
Signed-off-by: David Lin <dtwlin@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Michal Marek <mmarek@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
New features:
. Allow configuring a 'perf ftrace' default --tracer (Taeung Song)
Infrastructure:
. Sync tools/arch/{powerpc,arm}/include/uapi/asm/kvm.h and
tools/arch/x86/include/asm/cpufeatures.h (Ingo Molnar)
. Add BPF program file system pinning APIs and respective
'perf test' entry (Joe Stringer)
. Make tools tree support 'make -s' (Josh Poimboeuf)
. Reference count maps in callchains, fixing SEGFAULT when
referencing maps after it is freed (Krister Johansen)
. Create for_each_event trace points iterator (Taeung Song)
. Do not consider an error not to have any perfconfig file
(Arnaldo Carvalho de Melo
. Propagate perf_config() errors (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo-4.11-20170201' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
New features:
- Allow configuring a 'perf ftrace' default --tracer (Taeung Song)
Infrastructure changes:
- Sync tools/arch/{powerpc,arm}/include/uapi/asm/kvm.h and
tools/arch/x86/include/asm/cpufeatures.h (Ingo Molnar)
- Add BPF program file system pinning APIs and respective
'perf test' entry (Joe Stringer)
- Make tools tree support 'make -s' (Josh Poimboeuf)
- Reference count maps in callchains, fixing SEGFAULT when
referencing maps after it is freed (Krister Johansen)
- Create for_each_event trace points iterator (Taeung Song)
- Do not consider an error not to have any perfconfig file
(Arnaldo Carvalho de Melo
- Propagate perf_config() errors (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When doing a kernel build with 'make -s', everything is silenced except
the objtool build. That's because the tools tree support for silent
builds is some combination of missing and broken.
Three changes are needed to fix it:
- Makefile: propagate '-s' to the sub-make's MAKEFLAGS variable so the
tools Makefiles can see it.
- tools/scripts/Makefile.include: fix the tools Makefiles' ability to
recognize '-s'. The MAKE_VERSION and MAKEFLAGS checks are copied from
the top-level Makefile. This silences the "DESCEND objtool" message.
- tools/build/Makefile.build: add support to the tools Build files for
recognizing '-s'. Again the MAKE_VERSION and MAKEFLAGS checks are
copied from the top-level Makefile. This silences all the object
compile/link messages.
Reported-and-Tested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Michal Marek <mmarek@suse.com>
Link: http://lkml.kernel.org/r/e8967562ef640c3ae9a76da4ae0f4e47df737c34.1484799200.git.jpoimboe@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When building a specific target such as bzImage, modules aren't normally
built. However if CONFIG_TRIM_UNUSED_KSYMS is enabled, no built modules
means none of the exported symbols are used and therefore they will all
be trimmed away from the final kernel. A subsequent "make modules" will
fail because modpost cannot find the needed symbols for those modules in
the kernel binary.
Let's make sure modules are also built whenever CONFIG_TRIM_UNUSED_KSYMS
is enabled and that the kernel binary is properly rebuilt accordingly.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some people are able to trigger a race where autoksyms.h is used before
its empty version is even created. Let's create it at the same time as
the directory holding it is created.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Prarit Bhargava <prarit@redhat.com>
Tested-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull kbuild fixes from Michal Marek:
"Here are some regression fixes for kbuild:
- modversion support for exported asm symbols (Nick Piggin). The
affected architectures need separate patches adding
asm-prototypes.h.
- fix rebuilds of lib-ksyms.o (Nick Piggin)
- -fno-PIE builds (Sebastian Siewior and Borislav Petkov). This is
not a kernel regression, but one of the Debian gcc package.
Nevertheless, it's quite annoying, so I think it should go into
mainline and stable now"
* 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
kbuild: Steal gcc's pie from the very beginning
kbuild: be more careful about matching preprocessed asm ___EXPORT_SYMBOL
x86/kexec: add -fno-PIE
scripts/has-stack-protector: add -fno-PIE
kbuild: add -fno-PIE
kbuild: modversions for EXPORT_SYMBOL() for asm
kbuild: prevent lib-ksyms.o rebuilds
So Sebastian turned off the PIE for kernel builds but that was too late
- Kbuild.include already uses KBUILD_CFLAGS and trying to disable gcc
options with, say cc-disable-warning, fails:
gcc -D__KERNEL__ -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs
...
-Wno-sign-compare -fno-asynchronous-unwind-tables -Wframe-address -c -x c /dev/null -o .31392.tmp
/dev/null:1:0: error: code model kernel does not support PIC mode
because that returns an error and we can't disable the warning. For
example in this case:
KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
which leads to gcc issuing all those warnings again.
So let's turn off PIE/PIC at the earliest possible moment, when we
declare KBUILD_CFLAGS so that cc-disable-warning picks it up too.
Also, we need the $(call cc-option ...) because -fno-PIE is supported
since gcc v3.4 and our lowest supported gcc version is 3.2 right now.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Michal Marek <mmarek@suse.com>
Traditionally, we have always had warnings about uninitialized variables
enabled, as this is part of -Wall, and generally a good idea [1], but it
also always produced false positives, mainly because this is a variation
of the halting problem and provably impossible to get right in all cases
[2].
Various people have identified cases that are particularly bad for false
positives, and in commit e74fc973b6 ("Turn off -Wmaybe-uninitialized
when building with -Os"), I turned off the warning for any build that
was done with CC_OPTIMIZE_FOR_SIZE. This drastically reduced the number
of false positive warnings in the default build but unfortunately had
the side effect of turning the warning off completely in 'allmodconfig'
builds, which in turn led to a lot of warnings (both actual bugs, and
remaining false positives) to go in unnoticed.
With commit 877417e6ff ("Kbuild: change CC_OPTIMIZE_FOR_SIZE
definition") enabled the warning again for allmodconfig builds in v4.7
and in v4.8-rc1, I had finally managed to address all warnings I get in
an ARM allmodconfig build and most other maybe-uninitialized warnings
for ARM randconfig builds.
However, commit 6e8d666e92 ("Disable "maybe-uninitialized" warning
globally") was merged at the same time and disabled it completely for
all configurations, because of false-positive warnings on x86 that I had
not addressed until then. This caused a lot of actual bugs to get
merged into mainline, and I sent several dozen patches for these during
the v4.9 development cycle. Most of these are actual bugs, some are for
correct code that is safe because it is only called under external
constraints that make it impossible to run into the case that gcc sees,
and in a few cases gcc is just stupid and finds something that can
obviously never happen.
I have now done a few thousand randconfig builds on x86 and collected
all patches that I needed to address every single warning I got (I can
provide the combined patch for the other warnings if anyone is
interested), so I hope we can get the warning back and let people catch
the actual bugs earlier.
This reverts the change to disable the warning completely and for now
brings it back at the "make W=1" level, so we can get it merged into
mainline without introducing false positives. A follow-up patch enables
it on all levels unless some configuration option turns it off because
of false-positives.
Link: https://rusty.ozlabs.org/?p=232 [1]
Link: https://gcc.gnu.org/wiki/Better_Uninitialized_Warnings [2]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Debian started to build the gcc with -fPIE by default so the kernel
build ends before it starts properly with:
|kernel/bounds.c:1:0: error: code model kernel does not support PIC mode
Also add to KBUILD_AFLAGS due to:
|gcc -Wp,-MD,arch/x86/entry/vdso/vdso32/.note.o.d … -mfentry -DCC_USING_FENTRY … vdso/vdso32/note.S
|arch/x86/entry/vdso/vdso32/note.S:1:0: sorry, unimplemented: -mfentry isn’t supported for 32-bit in combination with -fpic
Tagging it stable so it is possible to compile recent stable kernels as
well.
Cc: stable@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Michal Marek <mmarek@suse.com>
This update consists of:
- Fixes and improvements to existing tests
- Moving code from Documentation to selftests, samples, and tools.
Moves dnotify_test, prctl, ptp, vDSO, ia64, watchdog, and networking
tests from Documentation to selftests.
Moves mic/mpssd, misc-devices/mei, timers, watchdog, auxdisplay, and
blackfin examples from Documentation to samples.
Moves accounting, laptops/dslm, and pcmcia/crc32hash tools from
Documentation to tools.
Deletes BUILD_DOCSRC and its dependencies.
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Merge tag 'linux-kselftest-4.9-rc1-update' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kselftest updates from Shuah Khan:
"This update consists of:
- Fixes and improvements to existing tests
- Moving code from Documentation to selftests, samples, and tools:
* Moves dnotify_test, prctl, ptp, vDSO, ia64, watchdog, and
networking tests from Documentation to selftests.
* Moves mic/mpssd, misc-devices/mei, timers, watchdog, auxdisplay,
and blackfin examples from Documentation to samples.
* Moves accounting, laptops/dslm, and pcmcia/crc32hash tools from
Documentation to tools.
* Deletes BUILD_DOCSRC and its dependencies"
* tag 'linux-kselftest-4.9-rc1-update' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (21 commits)
selftests/futex: Check ANSI terminal color support
Doc: update 00-INDEX files to reflect the runnable code move
samples: move blackfin gptimers-example from Documentation
tools: move pcmcia crc32hash tool from Documentation
tools: move laptops dslm tool from Documentation
tools: move accounting tool from Documentation
samples: move auxdisplay example code from Documentation
samples: move watchdog example code from Documentation
samples: move timers example code from Documentation
samples: move misc-devices/mei example code from Documentation
samples: move mic/mpssd example code from Documentation
selftests: Move networking/timestamping from Documentation
selftests: move watchdog tests from Documentation/watchdog
selftests: move ia64 tests from Documentation/ia64
selftests: move vDSO tests from Documentation/vDSO
selftests: move ptp tests from Documentation/ptp
selftests: move prctl tests from Documentation/prctl
selftests: move dnotify_test from Documentation/filesystems
selftests/timers: Add missing error code assignment before test
selftests/zram: replace ZRAM_LZ4_COMPRESS
...
Pull kbuild updates from Michal Marek:
- EXPORT_SYMBOL for asm source by Al Viro.
This does bring a regression, because genksyms no longer generates
checksums for these symbols (CONFIG_MODVERSIONS). Nick Piggin is
working on a patch to fix this.
Plus, we are talking about functions like strcpy(), which rarely
change prototypes.
- Fixes for PPC fallout of the above by Stephen Rothwell and Nick
Piggin
- fixdep speedup by Alexey Dobriyan.
- preparatory work by Nick Piggin to allow architectures to build with
-ffunction-sections, -fdata-sections and --gc-sections
- CONFIG_THIN_ARCHIVES support by Stephen Rothwell
- fix for filenames with colons in the initramfs source by me.
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (22 commits)
initramfs: Escape colons in depfile
ppc: there is no clear_pages to export
powerpc/64: whitelist unresolved modversions CRCs
kbuild: -ffunction-sections fix for archs with conflicting sections
kbuild: add arch specific post-link Makefile
kbuild: allow archs to select link dead code/data elimination
kbuild: allow architectures to use thin archives instead of ld -r
kbuild: Regenerate genksyms lexer
kbuild: genksyms fix for typeof handling
fixdep: faster CONFIG_ search
ia64: move exports to definitions
sparc32: debride memcpy.S a bit
[sparc] unify 32bit and 64bit string.h
sparc: move exports to definitions
ppc: move exports to definitions
arm: move exports to definitions
s390: move exports to definitions
m68k: move exports to definitions
alpha: move exports to actual definitions
x86: move exports to actual definitions
...
This affectively reverts commit 377ccbb483 ("Makefile: Mute warning
for __builtin_return_address(>0) for tracing only") because it turns out
that it really isn't tracing only - it's all over the tree.
We already also had the warning disabled separately for mm/usercopy.c
(which this commit also removes), and it turns out that we will also
want to disable it for get_lock_parent_ip(), that is used for at least
TRACE_IRQFLAGS. Which (when enabled) ends up being all over the tree.
Steven Rostedt had a patch that tried to limit it to just the config
options that actually triggered this, but quite frankly, the extra
complexity and abstraction just isn't worth it. We have never actually
had a case where the warning is actually useful, so let's just disable
it globally and not worry about it.
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move blackfin gptimers-example to samples and remove it from Documentation
Makefile. Update samples Kconfig and Makefile to build gptimers-example.
blackfin is the last CONFIG_BUILD_DOCSRC target in Documentation/Makefile.
Hence this patch also includes changes to remove CONFIG_BUILD_DOCSRC from
Makefile and lib/Kconfig.debug and updates VIDEO_PCI_SKELETON dependency
on BUILD_DOCSRC.
Documentation/Makefile is not deleted to avoid braking make htmldocs and
make distclean.
Acked-by: Michal Marek <mmarek@suse.com>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reported-by: Valentin Rothberg <valentinrothberg@gmail.com>
Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
The Sphinx transition is still creating a fair amount of work. Here we
have a number of fixes and, importantly, a proper PDF output solution,
thanks to Jani Nikula, Mauro Carvalho Chehab and Markus Heiser.
I've started a couple of new books: a driver API book (based on the old
device-drivers.tmpl) and a development tools book. Both are meant to show
how we can integrate together our existing documentation into a more
coherent and accessible whole. It involves moving some stuff around and
formatting changes, but, I think, the results are worth it. The good news
is that most of our existing Documentation/*.txt files are *almost* in RST
format already; the amount of messing around required is minimal.
And, of course, there's the usual set of updates, typo fixes, and more.
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Merge tag 'docs-4.9' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"This is the documentation update pull for the 4.9 merge window.
The Sphinx transition is still creating a fair amount of work. Here we
have a number of fixes and, importantly, a proper PDF output solution,
thanks to Jani Nikula, Mauro Carvalho Chehab and Markus Heiser.
I've started a couple of new books: a driver API book (based on the
old device-drivers.tmpl) and a development tools book. Both are meant
to show how we can integrate together our existing documentation into
a more coherent and accessible whole. It involves moving some stuff
around and formatting changes, but, I think, the results are worth it.
The good news is that most of our existing Documentation/*.txt files
are *almost* in RST format already; the amount of messing around
required is minimal.
And, of course, there's the usual set of updates, typo fixes, and
more"
* tag 'docs-4.9' of git://git.lwn.net/linux: (120 commits)
URL changed for Linux Foundation TAB
dax : Fix documentation with respect to struct pages
iio: Documentation: Correct the path used to create triggers.
docs: Remove space-before-label guidance from CodingStyle
docs-rst: add inter-document cross references
Documentation/email-clients.txt: convert it to ReST markup
Documentation/kernel-docs.txt: reorder based on timestamp
Documentation/kernel-docs.txt: Add dates for online docs
Documentation/kernel-docs.txt: get rid of broken docs
Documentation/kernel-docs.txt: move in-kernel docs
Documentation/kernel-docs.txt: remove more legacy references
Documentation/kernel-docs.txt: add two published books
Documentation/kernel-docs.txt: sort books per publication date
Documentation/kernel-docs.txt: adjust LDD references
Documentation/kernel-docs.txt: some improvements on the ReST output
Documentation/kernel-docs.txt: Consistent indenting: 4 spaces
Documentation/kernel-docs.txt: Add 4 paper/book references
Documentation/kernel-docs.txt: Improve layouting of book list
Documentation/kernel-docs.txt: Remove offline or outdated entries
docs: Clean up bare :: lines
...
Allow architectures to create arch/xxx/Makefile.postlink with targets
for vmlinux, modules.ko, and clean, which will be invoked after final
linking of vmlinux and modules.
powerpc will use this to check vmlinux linker relocations for sanity,
and may use it to fix up alternate instruction patch branch addresses.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
Introduce LD_DEAD_CODE_DATA_ELIMINATION option for architectures to
select to build with -ffunction-sections, -fdata-sections, and link
with --gc-sections. It requires some work (documented) to ensure all
unreferenced entrypoints are live, and requires toolchain and build
verification, so it is made a per-arch option for now.
On a random powerpc64le build, this yelds a significant size saving,
it boots and runs fine, but there is a lot I haven't tested as yet, so
these savings may be reduced if there are bugs in the link.
text data bss dec filename
11169741 1180744 1923176 14273661 vmlinux
10445269 1004127 1919707 13369103 vmlinux.dce
~700K text, ~170K data, 6% removed from kernel image size.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
Sphinx supports LaTeX output. Sometimes, it is interesting to
call it directly, instead of also generating a PDF. As it comes
for free, add a target for it.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
When the compiler doesn't support gcc plugins (either due to missing
headers or too old a version), report the problem and abort the build
instead of emitting a warning and letting the build founder with arcane
compiler errors.
Signed-off-by: Kees Cook <keescook@chromium.org>
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Merge tag 'media/v4.8-5' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media DocBook removal and some fixups from Mauro Carvalho Chehab:
- removal of the media DocBook (since it's all in Sphinx now)
- videobuf2: Fix an allocation regression
- a few fixes related to the CEC drivers
* tag 'media/v4.8-5' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
[media] cec: fix off-by-one memset
[media] staging: add MEDIA_SUPPORT dependency
[media] vivid: don't handle CEC_MSG_SET_STREAM_PATH
[media] media: adv7180: Fix broken interrupt register access
[media] vb2: Fix allocation size of dma_parms
[media] vim2m: copy the other colorspace-related fields as well
[media] adv7511: fix VIC autodetect
doc-rst: Remove the media docbook
. Move the suppressing of the __builtin_return_address >0 warning to the
tracing directory only.
. metag recordmcount fix for newer glibc's
. Two tracing histogram fixes that were reported by KASAN
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Merge tag 'trace-v4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"A few updates and fixes:
- move the suppressing of the __builtin_return_address >0 warning to
the tracing directory only.
- metag recordmcount fix for newer glibc's
- two tracing histogram fixes that were reported by KASAN"
* tag 'trace-v4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix use-after-free in hist_register_trigger()
tracing: Fix use-after-free in hist_unreg_all/hist_enable_unreg_all
Makefile: Mute warning for __builtin_return_address(>0) for tracing only
ftrace/recordmcount: Work around for addition of metag magic but not relocations
Pull kbuild updates from Michal Marek:
- GCC plugin support by Emese Revfy from grsecurity, with a fixup from
Kees Cook. The plugins are meant to be used for static analysis of
the kernel code. Two plugins are provided already.
- reduction of the gcc commandline by Arnd Bergmann.
- IS_ENABLED / IS_REACHABLE macro enhancements by Masahiro Yamada
- bin2c fix by Michael Tautschnig
- setlocalversion fix by Wolfram Sang
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
gcc-plugins: disable under COMPILE_TEST
kbuild: Abort build on bad stack protector flag
scripts: Fix size mismatch of kexec_purgatory_size
kbuild: make samples depend on headers_install
Kbuild: don't add obj tree in additional includes
Kbuild: arch: look for generated headers in obtree
Kbuild: always prefix objtree in LINUXINCLUDE
Kbuild: avoid duplicate include path
Kbuild: don't add ../../ to include path
vmlinux.lds.h: replace config_enabled() with IS_ENABLED()
kconfig.h: allow to use IS_{ENABLE,REACHABLE} in macro expansion
kconfig.h: use already defined macros for IS_REACHABLE() define
export.h: use __is_defined() to check if __KSYM_* is defined
kconfig.h: use __is_defined() to check if MODULE is defined
kbuild: setlocalversion: print error to STDERR
Add sancov plugin
Add Cyclomatic complexity GCC plugin
GCC plugin infrastructure
Shared library support
With the latest gcc compilers, they give a warning if
__builtin_return_address() parameter is greater than 0. That is because if
it is used by a function called by a top level function (or in the case of
the kernel, by assembly), it can try to access stack frames outside the
stack and crash the system.
The tracing system uses __builtin_return_address() of up to 2! But it is
well aware of the dangers that it may have, and has even added precautions
to protect against it (see the thunk code in arch/x86/entry/thunk*.S)
Linus originally added KBUILD_CFLAGS that would suppress the warning for the
entire kernel, as simply adding KBUILD_CFLAGS to the tracing directory
wouldn't work. The tracing directory plays a bit with the CFLAGS and
requires a little more logic.
This adds that special logic to only suppress the warning for the tracing
directory. If it is used anywhere else outside of tracing, the warning will
still be triggered.
Link: http://lkml.kernel.org/r/20160728223043.51996267@grimm.local.home
Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Now that all media documentation was converted to Sphinx, we
should get rid of the old DocBook one, as we don't want people
to submit patches against the old stuff.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Newer versions of gcc warn about the use of __builtin_return_address()
with a non-zero argument when "-Wall" is specified:
kernel/trace/trace_irqsoff.c: In function ‘stop_critical_timings’:
kernel/trace/trace_irqsoff.c:433:86: warning: calling ‘__builtin_return_address’ with a nonzero argument is unsafe [-Wframe-address]
stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
[ .. repeats a few times for other similar cases .. ]
It is true that a non-zero argument is somewhat dangerous, and we do not
actually have very many uses of that in the kernel - but the ftrace code
does use it, and as Stephen Rostedt says:
"We are well aware of the danger of using __builtin_return_address() of
> 0. In fact that's part of the reason for having the "thunk" code in
x86 (See arch/x86/entry/thunk_{64,32}.S). [..] it adds extra frames
when tracking irqs off sections, to prevent __builtin_return_address()
from accessing bad areas. In fact the thunk_32.S states: 'Trampoline to
trace irqs off. (otherwise CALLER_ADDR1 might crash)'."
For now, __builtin_return_address() with a non-zero argument is the best
we can do, and the warning is not helpful and can end up making people
miss other warnings for real problems.
So disable the frame-address warning on compilers that need it.
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds