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
Merge fixes for -Wmaybe-uninitialized from Arnd Bergmann:
"It took a while for some patches to make it into mainline through
maintainer trees, but the 28-patch series is now reduced to 10, with
one tiny patch added at the end.
Aside from patches that are no longer required, I did these changes
compared to version 1:
- Dropped "iio: maxim_thermocouple: detect invalid storage size in
read()", which is currently in linux-next as commit 32cb7d27e6.
This is the only remaining warning I see for a couple of corner
cases (kbuild bot reports it on blackfin, kernelci bot and arm-soc
bot both report it on arm64)
- Dropped "brcmfmac: avoid maybe-uninitialized warning in
brcmf_cfg80211_start_ap", which is currently in net/master merge
pending.
- Dropped two x86 patches, "x86: math-emu: possible uninitialized
variable use" and "x86: mark target address as output in 'insb'
asm" as they do not seem to trigger for a default build, and I got
no feedback on them. Both of these are ancient issues and seem
harmless, I will send them again to the x86 maintainers once the
rest is merged.
- Dropped "rbd: false-postive gcc-4.9 -Wmaybe-uninitialized" based on
feedback from Ilya Dryomov, who already has a different fix queued
up for v4.10. The kbuild bot reports this as a warning for xtensa.
- Replaced "crypto: aesni: avoid -Wmaybe-uninitialized warning" with
a simpler patch, this one always triggers but my first solution
would not be safe for linux-4.9 any more at this point. I'll follow
up with the larger patch as a cleanup for 4.10.
- Replaced "dib0700: fix nec repeat handling" with a better one,
contributed by Sean Young"
* -Wmaybe-uninitialized fixes:
Kbuild: enable -Wmaybe-uninitialized warnings by default
pcmcia: fix return value of soc_pcmcia_regulator_set
infiniband: shut up a maybe-uninitialized warning
crypto: aesni: shut up -Wmaybe-uninitialized warning
rc: print correct variable for z8f0811
dib0700: fix nec repeat handling
s390: pci: don't print uninitialized data for debugging
nios2: fix timer initcall return value
x86: apm: avoid uninitialized data
NFSv4.1: work around -Wmaybe-uninitialized warning
Kbuild: enable -Wmaybe-uninitialized warning for "make W=1"
Previously the warnings were added back at the W=1 level and above, this
now turns them on again by default, assuming that we have addressed all
warnings and again have a clean build for v4.10.
I found a number of new warnings in linux-next already and submitted
bugfixes for those. Hopefully they are caught by the 0day builder in
the future as soon as this patch is merged.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
Fix piping output to a program which quickly exits (read: head -n1)
$ ./scripts/bloat-o-meter ../vmlinux-000 ../obj/vmlinux | head -n1
add/remove: 0/0 grow/shrink: 9/60 up/down: 124/-305 (-181)
close failed in file object destructor:
sys.excepthook is missing
lost sys.stderr
Link: http://lkml.kernel.org/r/20161028204618.GA29923@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The CRC code for asm exports grabs the preprocessed asm, finds the
___EXPORT_SYMBOL and turns those into EXPORT_SYMBOL in a C program
that can be preprocessed and parsed to create the CRC signatures from
the type.
The existing regex matching and replacement is too strict, and doesn't
deal well with whitespace among other things. The line
" EXPORT_SYMBOL(sym)" in a .S file would not match due to initial
whitespace, for example, which resulted in x86's ___preempt_schedule
failing to get CRCs.
Reported-by: Philip Müller <philm@manjaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
Adding -no-PIE to the fstack protector check. -no-PIE was introduced
before -fstack-protector so there is no need for a runtime check.
Without it the build stops:
|Cannot use CONFIG_CC_STACKPROTECTOR_STRONG: -fstack-protector-strong available but compiler is broken
due to -mcmodel=kernel + -fPIE if -fPIE is enabled by default.
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>
Allow architectures to create asm/asm-prototypes.h file that
provides C prototypes for exported asm functions, which enables
proper CRC versions to be generated for them.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
The stack frame size could grow too large when the plugin used long long
on 32-bit architectures when the given function had too many basic blocks.
The gcc warning was:
drivers/pci/hotplug/ibmphp_ebda.c: In function 'ibmphp_access_ebda':
drivers/pci/hotplug/ibmphp_ebda.c:409:1: warning: the frame size of 1108 bytes is larger than 1024 bytes [-Wframe-larger-than=]
This switches latent_entropy from u64 to unsigned long.
Thanks to PaX Team and Emese Revfy for the patch.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reported-by: Russell King <rmk+kernel@armlinux.org.uk>
Tested-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Michal Marek <mmarek@suse.com>
extract as much possible uncertainty from a running system at boot time as
possible, hoping to capitalize on any possible variation in CPU operation
(due to runtime data differences, hardware differences, SMP ordering,
thermal timing variation, cache behavior, etc).
At the very least, this plugin is a much more comprehensive example for
how to manipulate kernel code using the gcc plugin internals.
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Merge tag 'gcc-plugins-v4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull gcc plugins update from Kees Cook:
"This adds a new gcc plugin named "latent_entropy". It is designed to
extract as much possible uncertainty from a running system at boot
time as possible, hoping to capitalize on any possible variation in
CPU operation (due to runtime data differences, hardware differences,
SMP ordering, thermal timing variation, cache behavior, etc).
At the very least, this plugin is a much more comprehensive example
for how to manipulate kernel code using the gcc plugin internals"
* tag 'gcc-plugins-v4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
latent_entropy: Mark functions with __latent_entropy
gcc-plugins: Add latent_entropy plugin
Pull misc kbuild changes from Michal Marek:
"Just a few patches on the kbuild.git#misc branch this time:
- New Coccinelle patch by Nicholas Mc Guire
- Existing patch fixes by Julia Lawall
- Minor comment fix by Markus Elfring"
* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
Coccinelle: flag conditions with no effect
scripts/coccicheck: Update reference for the corresponding documentation
Coccinelle: pm_runtime: ensure relevance of pm_runtime reports
Coccinelle: limit memdup_user transformation to GFP_KERNEL case
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
...
The function calls with octal permissions commonly span multiple lines.
The current test is line oriented and fails to find some matches.
Make the test use the $stat variable instead of the $line variable to span
multiple lines.
Also add a few functions to the known functions with permissions list.
Move the SYMBOLIC_PERMS test to a separate section to find all the S_<FOO>
permissions in any form not just those that have specific function names.
This can now find and fix permissions uses like:
.mode = S_<FOO> | S_<BAR>;
Link: http://lkml.kernel.org/r/b51bab60530912aae4ac420119d465c5b206f19f.1475030406.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Tested-by: Ramiro Oliveira <roliveir@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It is possible for a multiple line macro definition to have a false positive
report when an argument is used on a line after a continuation \.
This line might have a leading '+' as the initial character that could be
confused by checkpatch as an operator.
Avoid the leading character on multiple line macro definitions.
Link: http://lkml.kernel.org/r/60229d13399f9b6509db5a32e30d4c16951a60cd.1473836073.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a test for macro arguents that have a non-comma leading or trailing
operator where the argument isn't parenthesized to avoid possible precedence
issues.
Link: http://lkml.kernel.org/r/47715508972f8d786f435e583ff881dbeee3a114.1473745855.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If a macro argument is used multiple times in the macro definition, the
macro argument may have an unexpected side-effect.
Add a test (MACRO_ARG_REUSE) for that condition which is only
emitted with command-line option --strict.
Link: http://lkml.kernel.org/r/b6d67a87cafcafd15499e91780dc63b15dec0aa0.1473744906.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
An "uninitialized value" is emitted when a block comment starts on
the same line as a statement.
Fix this and make the test use a little fewer cpu cycles too.
Link: http://lkml.kernel.org/r/3c9993320c2182d37f53ac540878cfef59c3f62d.1473365956.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Charlemagne Lasse <charlemagnelasse@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Adding -f to the get_maintainer.pl invocation means git isn't invoked
by get_maintainer.pl for known filenames.
This reduces the overall time to run checkpatch.
Link: http://lkml.kernel.org/r/22991e3a295aeb399b43af0478b6e5809106ccee.1472684066.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Using const is generally a good idea.
Julia Lawall has created a list of always const and almost always const
structs in the kernel sources.
Link: https://lkml.org/lkml/2016/8/28/95
Add the most frequently used (> 50 cases) that are almost always or
always const.
Link: http://lkml.kernel.org/r/1e16020f8027654db0095bbfbcc11da51025365c.1472664220.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make it easier to add new structs that should be const.
Link: http://lkml.kernel.org/r/e5a8da43e7c11525bafbda1ca69a8323614dd942.1472664220.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
< sigh > Comment these tests out.
These are just too enticing to people that don't verify that
both source and dest addresses really must be __aligned(2).
It helps make Dan Carpenter happy too.
Link: http://lkml.kernel.org/r/dc32ec66d24647f4cdf824c8dfbbc59aa7ce7b7d.1472665676.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Greg <gvrose8192@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
S_<FOO> uses should be avoided where octal is more intelligible.
Linus didst say:
: It's *much* easier to parse and understand the octal numbers, while the
: symbolic macro names are just random line noise and hard as hell to
: understand. You really have to think about it.
:
: So we should rather go the other way: convert existing bad symbolic
: permission bit macro use to just use the octal numbers.
:
: The symbolic names are good for the *other* bits (ie sticky bit, and the
: inode mode _type_ numbers etc), but for the permission bits, the symbolic
: names are just insane crap. Nobody sane should ever use them. Not in the
: kernel, not in user space.
(http://lkml.kernel.org/r/CA+55aFw5v23T-zvDZp-MmD_EYxF8WbafwwB59934FV7g21uMGQ@mail.gmail.com)
Link: http://lkml.kernel.org/r/7232ef011d05a92f4caa86a5e9830d87966a2eaf.1470180926.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use get_maintainer to check the status of individual files. If
"obsolete", suggest leaving the files alone.
Link: http://lkml.kernel.org/r/7ceaa510dc9d2df05ec4b456baed7bb1415550b3.1471889575.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: SF Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Report code constructs where the if and else branch are functionally
identical. In cases where this is intended it really should be
documented - most reported cases probably are bugs.
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
Use the current name (in a comment at the beginning of this script) for
the file which was converted to the documentation format "reStructuredText"
in August 2016.
Fixes: 4b9033a334 ("docs: sphinxify coccinelle.txt and add it to dev-tools")
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.com>
This adds a new gcc plugin named "latent_entropy". It is designed to
extract as much possible uncertainty from a running system at boot time as
possible, hoping to capitalize on any possible variation in CPU operation
(due to runtime data differences, hardware differences, SMP ordering,
thermal timing variation, cache behavior, etc).
At the very least, this plugin is a much more comprehensive example for
how to manipulate kernel code using the gcc plugin internals.
The need for very-early boot entropy tends to be very architecture or
system design specific, so this plugin is more suited for those sorts
of special cases. The existing kernel RNG already attempts to extract
entropy from reliable runtime variation, but this plugin takes the idea to
a logical extreme by permuting a global variable based on any variation
in code execution (e.g. a different value (and permutation function)
is used to permute the global based on loop count, case statement,
if/then/else branching, etc).
To do this, the plugin starts by inserting a local variable in every
marked function. The plugin then adds logic so that the value of this
variable is modified by randomly chosen operations (add, xor and rol) and
random values (gcc generates separate static values for each location at
compile time and also injects the stack pointer at runtime). The resulting
value depends on the control flow path (e.g., loops and branches taken).
Before the function returns, the plugin mixes this local variable into
the latent_entropy global variable. The value of this global variable
is added to the kernel entropy pool in do_one_initcall() and _do_fork(),
though it does not credit any bytes of entropy to the pool; the contents
of the global are just used to mix the pool.
Additionally, the plugin can pre-initialize arrays with build-time
random contents, so that two different kernel builds running on identical
hardware will not have the same starting values.
Signed-off-by: Emese Revfy <re.emese@gmail.com>
[kees: expanded commit message and code comments]
Signed-off-by: Kees Cook <keescook@chromium.org>
No need to correct the correct.
Link: http://lkml.kernel.org/r/1472490791.3425.38.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When doing an nmi backtrace of many cores, most of which are idle, the
output is a little overwhelming and very uninformative. Suppress
messages for cpus that are idling when they are interrupted and just
emit one line, "NMI backtrace for N skipped: idling at pc 0xNNN".
We do this by grouping all the cpuidle code together into a new
.cpuidle.text section, and then checking the address of the interrupted
PC to see if it lies within that section.
This commit suitably tags x86 and tile idle routines, and only adds in
the minimal framework for other architectures.
Link: http://lkml.kernel.org/r/1472487169-14923-5-git-send-email-cmetcalf@mellanox.com
Signed-off-by: Chris Metcalf <cmetcalf@mellanox.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Daniel Thompson <daniel.thompson@linaro.org> [arm]
Tested-by: Petr Mladek <pmladek@suse.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The big change is the addition of the hwlat tracer. It not only detects
SMIs, but also other latency that's caused by the hardware. I have detected
some latency from large boxes having bus contention.
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Merge tag 'trace-v4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"This release cycle is rather small. Just a few fixes to tracing.
The big change is the addition of the hwlat tracer. It not only
detects SMIs, but also other latency that's caused by the hardware. I
have detected some latency from large boxes having bus contention"
* tag 'trace-v4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Call traceoff trigger after event is recorded
ftrace/scripts: Add helper script to bisect function tracing problem functions
tracing: Have max_latency be defined for HWLAT_TRACER as well
tracing: Add NMI tracing in hwlat detector
tracing: Have hwlat trace migrate across tracing_cpumask CPUs
tracing: Add documentation for hwlat_detector tracer
tracing: Added hardware latency tracer
ftrace: Access ret_stack->subtime only in the function profiler
function_graph: Handle TRACE_BPUTS in print_graph_comment
tracing/uprobe: Drop isdigit() check in create_trace_uprobe
Pull s390 updates from Martin Schwidefsky:
"The new features and main improvements in this merge for v4.9
- Support for the UBSAN sanitizer
- Set HAVE_EFFICIENT_UNALIGNED_ACCESS, it improves the code in some
places
- Improvements for the in-kernel fpu code, in particular the overhead
for multiple consecutive in kernel fpu users is recuded
- Add a SIMD implementation for the RAID6 gen and xor operations
- Add RAID6 recovery based on the XC instruction
- The PCI DMA flush logic has been improved to increase the speed of
the map / unmap operations
- The time synchronization code has seen some updates
And bug fixes all over the place"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (48 commits)
s390/con3270: fix insufficient space padding
s390/con3270: fix use of uninitialised data
MAINTAINERS: update DASD maintainer
s390/cio: fix accidental interrupt enabling during resume
s390/dasd: add missing \n to end of dev_err messages
s390/config: Enable config options for Docker
s390/dasd: make query host access interruptible
s390/dasd: fix panic during offline processing
s390/dasd: fix hanging offline processing
s390/pci_dma: improve lazy flush for unmap
s390/pci_dma: split dma_update_trans
s390/pci_dma: improve map_sg
s390/pci_dma: simplify dma address calculation
s390/pci_dma: remove dma address range check
iommu/s390: simplify registration of I/O address translation parameters
s390: migrate exception table users off module.h and onto extable.h
s390: export header for CLP ioctl
s390/vmur: fix irq pointer dereference in int handler
s390/dasd: add missing KOBJ_CHANGE event for unformatted devices
s390: enable UBSAN
...
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
...
Here's the "big" char and misc driver update for 4.9-rc1.
Lots of little things here, all over the driver tree for subsystems that
flow through me. Nothing major that I can discern, full details are in
the shortlog.
All have been in the linux-next tree with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH:
"Here's the "big" char and misc driver update for 4.9-rc1.
Lots of little things here, all over the driver tree for subsystems
that flow through me. Nothing major that I can discern, full details
are in the shortlog.
All have been in the linux-next tree with no reported issues"
* tag 'char-misc-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (144 commits)
drivers/misc/hpilo: Changes to support new security states in iLO5 FW
at25: fix debug and error messaging
misc/genwqe: ensure zero initialization
vme: fake: remove unexpected unlock in fake_master_set()
vme: fake: mark symbols static where possible
spmi: pmic-arb: Return an error code if sanity check fails
Drivers: hv: get rid of id in struct vmbus_channel
Drivers: hv: make VMBus bus ids persistent
mcb: Add a dma_device to mcb_device
mcb: Enable PCI bus mastering by default
mei: stop the stall timer worker if not needed
clk: probe common clock drivers earlier
vme: fake: fix build for 64-bit dma_addr_t
ttyprintk: Neaten and simplify printing
mei: me: add kaby point device ids
coresight: tmc: mark symbols static where possible
coresight: perf: deal with error condition properly
Drivers: hv: hv_util: Avoid dynamic allocation in time synch
fpga manager: Add hardware dependency to Zynq driver
Drivers: hv: utils: Support TimeSync version 4.0 protocol samples.
...
pm_runtime.cocci starts with one rule that searches for a variety of
functions calls, followed by various rules that report errors. Previously,
the only connection between the first rule and the rest was to check that
the first rule had matched somewhere. Change the rules to propagate a
position from the first rule to the others, to make sure that the sites
reported on are the same as the sites that were identified as having the
relevant functions.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.com>
Memdup_user encapsulates a memory allocation with the flag GFP_KERNEL, so
only allow this flag in the original code.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.com>
be7635e728 ("arch, ftrace: for KASAN put hard/soft IRQ entries into
separate sections") added .softirqentry.text section, but it was not added
to recordmcount. So functions in the section are untracable. Add the
section to scripts/recordmcount.c and scripts/recordmcount.pl.
Fixes: be7635e728 ("arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections")
Link: http://lkml.kernel.org/r/1474902626-73468-1-git-send-email-dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Steve Rostedt <rostedt@goodmis.org>
Cc: <stable@vger.kernel.org> [4.6+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Special characters are problematic in depfiles, but we can fix colons
easily.
Reported-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
Every so often, with a special config or a architecture change, running
function or function_graph tracing can cause the machien to hard reboot,
crash, or simply hard lockup. There's some functions in the function graph
tracer that can not be traced otherwise it causes the function tracer to
recurse before the recursion protection mechanisms are in place.
When this occurs, using the dynamic ftrace featuer that allows limiting what
actually gets traced can be used to bisect down to the problem function.
This adds a script that helps with this process in the scripts/tracing
directory, called ftrace-bisect.sh
The set up is to read all the functions that can be traced from
available_filter_functions into a file (full_file). Then run this script
passing it the full_file and a "test_file" and "non_test_file", where the
test_file will be add to set_ftrace_filter. What ftarce_bisect.sh does, is
to copy half of the functions in full_file into the test_file and the other
half into the non_test_file. This way, one can cat the test_file into the
set_ftrace_filter functions and only test the functions that are in that
file. If it works, then we run the process again after copying non_test_file
to full_file and repeating the process. If the system crashed, then the bad
function is in the test_file and after a reboot, the test_file becomes the
new full_file in the next iteration.
When we get down to a single function in the full_file, then
ftrace_bisect.sh will report that as the bad function.
Full documentation of how to use this simple script is within the script
file itself.
Link: http://lkml.kernel.org/r/20160920100716.131d3647@gandalf.local.home
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Some architectures use a hardware defined structure at address zero.
Checking for a null pointer will result in many ubsan reports.
Allow users to disable the null sanitizer.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Due to our compiler include directives, the build pathnames for header
files often end up being of the form "$srcdir/./include/linux/xyz.h",
which ends up having that extra "." path component after the build base
in it.
Teach faddr2line to skip that too, to make code generated in inline
functions in header files match the filename for the regular C files.
Rabin Vincent pointed out that I can't make a stricter regexp match by
using the " at " prefix for the pathname, because that ends up being
locale-dependent. But this does require that the path match be preceded
by a space, to make it a bit more strict (that matters mainly if we
didn't find any base_dir at all, and we only end up with the "./" part
of the match)
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Rabin Vincent <rabin@rab.in>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
addr2line doesn't work with KASLR addresses. Add a basic addr2line
wrapper script which takes the 'func+offset/size' format as input.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
ld -r is an incremental link used to create built-in.o files in build
subdirectories. It produces relocatable object files containing all
its input files, and these are are then pulled together and relocated
in the final link. Aside from the bloat, this constrains the final
link relocations, which has bitten large powerpc builds with
unresolvable relocations in the final link.
Alan Modra has recommended the kernel use thin archives for linking.
This is an alternative and means that the linker has more information
available to it when it links the kernel.
This patch enables a config option architectures can select, which
causes all built-in.o files to be built as thin archives. built-in.o
files in subdirectories do not get symbol table or index attached,
which improves speed and size. The final link pass creates a
built-in.o archive in the root output directory which includes the
symbol table and index. The linker then uses takes this file to link.
The --whole-archive linker option is required, because the linker now
has visibility to every individual object file, and it will otherwise
just completely avoid including those without external references
(consider a file with EXPORT_SYMBOL or initcall or hardware exceptions
as its only entry points). The traditional built works "by luck" as
built-in.o files are large enough that they're going to get external
references. However this optimisation is unpredictable for the kernel
(due to above external references), ineffective at culling unused, and
costly because the .o files have to be searched for references.
Superior alternatives for link-time culling should be used instead.
Build characteristics for inclink vs thinarc, on a small powerpc64le
pseries VM with a modest .config:
inclink thinarc
sizes
vmlinux 15 618 680 15 625 028
sum of all built-in.o 56 091 808 1 054 334
sum excluding root built-in.o 151 430
find -name built-in.o | xargs rm ; time make vmlinux
real 22.772s 21.143s
user 13.280s 13.430s
sys 4.310s 2.750s
- Final kernel pulled in only about 6K more, which shows how
ineffective the object file culling is.
- Build performance looks improved due to less pagecache activity.
On IO constrained systems it could be a bigger win.
- Build size saving is significant.
Side note, the toochain understands archives, so there's some tricks,
$ ar t built-in.o # list all files you linked with
$ size built-in.o # and their sizes
$ objdump -d built-in.o # disassembly (unrelocated) with filenames
Implementation by sfr, minor tweaks by npiggin.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
Add yet another regex to kernel-doc to trap @param() references separately
and not produce corrupt RST markup.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
As far as I can tell, the handling of "..." arguments has never worked
right, so any documentation provided was ignored in favor of "variable
arguments." This makes kernel-doc handle "@...:" as documented. It does
*not* fix spots in kerneldoc comments that don't follow that convention,
but they are no more broken than before.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
