01 Aug, 2014
2 commits
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commit 2062afb4f804afef61cbe62a30cac9a46e58e067 upstream.
Michel Dänzer and a couple of other people reported inexplicable random
oopses in the scheduler, and the cause turns out to be gcc mis-compiling
the load_balance() function when debugging is enabled. The gcc bug
apparently goes back to gcc-4.5, but slight optimization changes means
that it now showed up as a problem in 4.9.0 and 4.9.1.The instruction scheduling problem causes gcc to schedule a spill
operation to before the stack frame has been created, which in turn can
corrupt the spilled value if an interrupt comes in. There may be other
effects of this bug too, but that's the code generation problem seen in
Michel's case.This is fixed in current gcc HEAD, but the workaround as suggested by
Markus Trippelsdorf is pretty simple: use -fno-var-tracking-assignments
when compiling the kernel, which disables the gcc code that causes the
problem. This can result in slightly worse debug information for
variable accesses, but that is infinitely preferable to actual code
generation problems.Doing this unconditionally (not just for CONFIG_DEBUG_INFO) also allows
non-debug builds to verify that the debug build would be identical: we
can doexport GCC_COMPARE_DEBUG=1
to make gcc internally verify that the result of the build is
independent of the "-g" flag (it will make the compiler build everything
twice, toggling the debug flag, and compare the results).Without the "-fno-var-tracking-assignments" option, the build would fail
(even with 4.8.3 that didn't show the actual stack frame bug) with a gcc
compare failure.See also gcc bugzilla:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61801
Reported-by: Michel Dänzer
Suggested-by: Markus Trippelsdorf
Cc: Jakub Jelinek
Signed-off-by: Linus Torvalds
Signed-off-by: Greg Kroah-Hartman
28 Jul, 2014
1 commit
18 Jul, 2014
1 commit
10 Jul, 2014
1 commit
07 Jul, 2014
1 commit
01 Jul, 2014
1 commit
27 Jun, 2014
1 commit
17 Jun, 2014
1 commit
09 Jun, 2014
1 commit
02 Jun, 2014
1 commit
26 May, 2014
1 commit
22 May, 2014
1 commit
10 May, 2014
1 commit
05 May, 2014
1 commit
28 Apr, 2014
1 commit
21 Apr, 2014
1 commit
14 Apr, 2014
1 commit
13 Apr, 2014
1 commit
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Pull misc kbuild changes from Michal Marek:
"Here is the non-critical part of kbuild:
- One bogus coccinelle check removed, one check fixed not to suggest
the obsolete PTR_RET macro
- scripts/tags.sh does not index the generated *.mod.c files
- new objdiff tool to list differences between two versions of an
object file
- A fix for scripts/bootgraph.pl"* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
scripts/coccinelle: Use PTR_ERR_OR_ZERO
scripts/bootgraph.pl: Add graphic header
scripts: objdiff: detect object code changes between two commits
Coccicheck: Remove memcpy to struct assignment test
scripts/tags.sh: Ignore *.mod.c
10 Apr, 2014
1 commit
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Add support to toplevel Makefile for compiling with clang, both for
HOSTCC and CC. Use cc-option to prevent gcc option from breaking clang, and
from clang options from breaking gcc.Clang 3.4 semantics are the same as gcc semantics for unsupported flags. For
unsupported warnings clang 3.4 returns true but shows a warning and gcc shows
a warning and returns false.Signed-off-by: Behan Webster
Signed-off-by: Jan-Simon Möller
Signed-off-by: Mark Charlebois
Cc: PaX Team
08 Apr, 2014
2 commits
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objdiff is useful when doing large code cleanups. For example, when
removing checkpatch warnings and errors from new drivers in the staging
tree.objdiff can be used in conjunction with a git rebase to confirm that
each commit made no changes to the resulting object code. It has the
same return values as diff(1).This was written specifically to support adding the skein and threefish
cryto drivers to the staging tree. I needed a programmatic way to
confirm that commits changing >90% of the lines didn't inadvertently
change the code.Temporary files (objdump output) are stored in
/path/to/linux/.tmp_objdiff
'make mrproper' will remove this directory.
Signed-off-by: Jason Cooper
Signed-off-by: Michal Marek -
Pull kbuild changes from Michal Marek:
- cleanups in the main Makefiles and Documentation/DocBook/Makefile
- make O=... directory is automatically created if needed
- mrproper/distclean removes the old include/linux/version.h to make
life easier when bisecting across the commit that moved the version.h
file* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
kbuild: docbook: fix the include error when executing "make help"
kbuild: create a build directory automatically for out-of-tree build
kbuild: remove redundant '.*.cmd' pattern from make distclean
kbuild: move "quote" to Kbuild.include to be consistent
kbuild: docbook: use $(obj) and $(src) rather than specific path
kbuild: unconditionally clobber include/linux/version.h on distclean
kbuild: docbook: specify KERNELDOC dependency correctly
kbuild: docbook: include cmd files more simply
kbuild: specify build_docproc as a phony target
03 Apr, 2014
1 commit
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Pull devicetree changes from Grant Likely:
"Updates to devicetree core code. This branch contains the following
notable changes:- add reserved memory binding
- make struct device_node a kobject and remove legacy
/proc/device-tree
- ePAPR conformance fixes
- update in-kernel DTC copy to version v1.4.0
- preparatory changes for dynamic device tree overlays
- minor bug fixes and documentation changesThe most significant change in this branch is the conversion of struct
device_node to be a kobject that is exposed via sysfs and removal of
the old /proc/device-tree code. This simplifies the device tree
handling code and tightens up the lifecycle on device tree nodes.[updated: added fix for dangling select PROC_DEVICETREE]"
* tag 'dt-for-linus' of git://git.secretlab.ca/git/linux: (29 commits)
dt: Remove dangling "select PROC_DEVICETREE"
of: Add support for ePAPR "stdout-path" property
of: device_node kobject lifecycle fixes
of: only scan for reserved mem when fdt present
powerpc: add support for reserved memory defined by device tree
arm64: add support for reserved memory defined by device tree
of: add missing major vendors
of: add vendor prefix for SMSC
of: remove /proc/device-tree
of/selftest: Add self tests for manipulation of properties
of: Make device nodes kobjects so they show up in sysfs
arm: add support for reserved memory defined by device tree
drivers: of: add support for custom reserved memory drivers
drivers: of: add initialization code for dynamic reserved memory
drivers: of: add initialization code for static reserved memory
of: document bindings for reserved-memory nodes
Revert "of: fix of_update_property()"
kbuild: dtbs_install: new make target
ARM: mvebu: Allows to get the SoC ID even without PCI enabled
of: Allows to use the PCI translator without the PCI core
...
01 Apr, 2014
2 commits
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Kbuild supports saving output files in a separate directory.
But the build directory must be created beforehand. For example,$ mkdir -p dir/to/store/output/files
$ make O=dir/to/store/output/files defconfigCreating a build directory automatically would be useful.
Signed-off-by: Masahiro Yamada
Acked-by: Sam Ravnborg
Signed-off-by: Michal Marek -
'.*.cmd' files are cleaned-up by "make clean".
The same pattern in "make distclean" is unnecessary.Signed-off-by: Masahiro Yamada
Signed-off-by: Michal Marek
31 Mar, 2014
2 commits
30 Mar, 2014
1 commit
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As of v3.7, the UAPI changes relocated headers around such that the
kernel version header lived in a new place.If a person is bisecting and if you go back to pre-UAPI days,
you will create an include/linux/version.h -- then if you checkout a
post-UAPI kernel, and even run "make distclean" it still won't delete
that old version file. So you get a situation like this:$ grep -R LINUX_VERSION_CODE include/
include/generated/uapi/linux/version.h:#define LINUX_VERSION_CODE 200192
include/linux/version.h:#define LINUX_VERSION_CODE 132646The value in that second line is representative of a v2.6.38 version.
And it will be sourced/used, hence leading to strange behaviours, such
as drivers/staging content (which typically hasn't been purged of version
ifdefs) failing to build.Since it is a subtle mode of failure, lets always clobber the old
file when doing a distclean.Signed-off-by: Paul Gortmaker
Acked-by: David Howells
Signed-off-by: Michal Marek
25 Mar, 2014
1 commit
17 Mar, 2014
1 commit
10 Mar, 2014
1 commit
04 Mar, 2014
1 commit
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Linux 3.14-rc5
03 Mar, 2014
1 commit
26 Feb, 2014
2 commits
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According to Documentation/Changes, make 3.80 is still being supported
for building the kernel, hence make files must not make (unconditional)
use of features introduced only in newer versions. Commit 8779657d29c0
("stackprotector: Introduce CONFIG_CC_STACKPROTECTOR_STRONG") however
introduced an "else ifdef" construct which make 3.80 doesn't understand.Also correct a warning message still referencing the old config option
name.Apart from that I question the use of "ifdef" here (but it was used that
way already prior to said commit): ifeq (,y) would seem more to the
point.Signed-off-by: Jan Beulich
Acked-by: Kees Cook
Cc: Ingo Molnar
Cc: Michal Marek
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
An extra parenthesis typo introduced in 19952a92037e ("stackprotector:
Unify the HAVE_CC_STACKPROTECTOR logic between architectures") is
causing the following error when CONFIG_CC_STACKPROTECTOR_REGULAR is
enabled:Makefile:608: Cannot use CONFIG_CC_STACKPROTECTOR: -fstack-protector not supported by compiler
Makefile:608: *** missing separator. Stop.Signed-off-by: Fathi Boudra
Acked-by: Kees Cook
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
24 Feb, 2014
1 commit
20 Feb, 2014
1 commit
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Unlike other build products in the Linux kernel, there is no 'make
*install' mechanism to put devicetree blobs in a standard place.This commit adds a new 'dtbs_install' make target which copies all of
the dtbs into the INSTALL_DTBS_PATH directory. INSTALL_DTBS_PATH can be
set before calling make to change the default install directory. If not
set then it defaults to:$INSTALL_PATH/dtbs/$KERNELRELEASE.
This is done to keep dtbs from different kernel versions separate until
things have settled down. Once the dtbs are stable, and not so strongly
linked to the kernel version, the devicetree files will most likely move
to their own repo. Users will need to upgrade install scripts at that
time.v7: (reworked by Grant Likely)
- Moved rules from arch/arm/Makefile to arch/arm/boot/dts/Makefile so
that each dtb install could have a separate target and be reported as
part of the make output.
- Fixed dependency problem to ensure $KERNELRELEASE is calculated before
attempting to install
- Removed option to call external script. Copying the files should be
sufficient and a build system can post-process the install directory.
Despite the fact an external script is used for installing the kernel,
I don't think that is a pattern that should be encouraged. I would
rather see buildroot type tools post process the install directory to
rename or move dtb files after installing to a staging directory.
- Plus it is easy to add a hook after the fact without blocking the
rest of this feature.
- Move the helper targets into scripts/Makefile.lib with the rest of the
common dtb rulesSigned-off-by: Jason Cooper
Signed-off-by: Grant Likely
Cc: Michal Marek
Cc: Russell King
Cc: Rob Herring
17 Feb, 2014
1 commit
10 Feb, 2014
1 commit
06 Feb, 2014
1 commit
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CONFIG_MODVERSIONS=y results in a .mod.c for every compiled file in the
kernel. Issuing a 'make cscope' on a compiled kernel tree results in
the cscope files containing *.mod.c files.[prarit@prarit linux]# make cscope
[prarit@prarit linux]# cat cscope.files | grep mod.c | wc -l
4807These files are not useful for cscope and should be ignored. For example,
# line filename / context / line
1 105 arch/x86/kvm/kvm-intel.mod.c <>
{ 0x618911fc, __VMLINUX_SYMBOL_STR(numa_node) },
2 508 drivers/block/mtip32xx/mtip32xx.h <>
int numa_node;
3 55 drivers/block/mtip32xx/mtip32xx.mod.c <>
{ 0x618911fc, __VMLINUX_SYMBOL_STR(numa_node) },
4 37 drivers/cpufreq/acpi-cpufreq.mod.c <>
{ 0x618911fc, __VMLINUX_SYMBOL_STR(numa_node) },
Add an export to RCS_FIND_IGNORE so it can be used in scripts/tags.sh
and add explicitly ignore *.mod.c files.Signed-off-by: Prarit Bhargava
Cc: Andrew Morton
Cc: Kirill Tkhai
Cc: Michael Opdenacker
Cc: Rusty Russell
Signed-off-by: Michal Marek
