3509 Commits

Author SHA1 Message Date
Jani Nikula
fadc0b31cb kernel-doc: rewrite usage description, remove duplicated comments
Instead of having the kernel-doc usage in both comments and in output to
the user, merge them all to one here document. While at it, imrove the
text and make it pretty. Give shoemaker's children some shoes.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2016-05-14 09:56:25 -06:00
Maciej W. Rozycki
0d61ed17dd ld-version: Drop the 4th and 5th version components
... making upstream development binutils snapshots work as expected,
e.g.:

$ mips64el-linux-ld --version
GNU ld (GNU Binutils) 2.20.1.20100303
[...]
$

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Acked-by: Michal Marek <mmarek@suse.cz>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-kbuild@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12537/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:05 +02:00
Arnd Bergmann
c9c6837d39 kbuild: move -Wunused-const-variable to W=1 warning level
gcc-6 started warning by default about variables that are not
used anywhere and that are marked 'const', generating many
false positives in an allmodconfig build, e.g.:

arch/arm/mach-davinci/board-da830-evm.c:282:20: warning: 'da830_evm_emif25_pins' defined but not used [-Wunused-const-variable=]
arch/arm/plat-omap/dmtimer.c:958:34: warning: 'omap_timer_match' defined but not used [-Wunused-const-variable=]
drivers/bluetooth/hci_bcm.c:625:39: warning: 'acpi_bcm_default_gpios' defined but not used [-Wunused-const-variable=]
drivers/char/hw_random/omap-rng.c:92:18: warning: 'reg_map_omap4' defined but not used [-Wunused-const-variable=]
drivers/devfreq/exynos/exynos5_bus.c:381:32: warning: 'exynos5_busfreq_int_pm' defined but not used [-Wunused-const-variable=]
drivers/dma/mv_xor.c:1139:34: warning: 'mv_xor_dt_ids' defined but not used [-Wunused-const-variable=]

This is similar to the existing -Wunused-but-set-variable warning
that was added in an earlier release and that we disable by default
now and only enable when W=1 is set, so it makes sense to do
the same here. Once we have eliminated the majority of the
warnings for both, we can put them back into the default list.

We probably want this in backport kernels as well, to allow building
them with gcc-6 without introducing extra warnings.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Lee Jones <lee.jones@linaro.org>
Cc: stable@vger.kernel.org
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-11 13:05:40 +02:00
Masahiro Yamada
9c8fa9bc08 kbuild: fix if_change and friends to consider argument order
Currently, arg-check is implemented as follows:

  arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \
                      $(filter-out $(cmd_$@),   $(cmd_$(1))) )

This does not care about the order of arguments that appear in
$(cmd_$(1)) and $(cmd_$@).  So, if_changed and friends never rebuild
the target if only the argument order is changed.  This is a problem
when the link order is changed.

Apparently,

  obj-y += foo.o
  obj-y += bar.o

and

  obj-y += bar.o
  obj-y += foo.o

should be distinguished because the link order determines the probe
order of drivers.  So, built-in.o should be rebuilt when the order
of objects is changed.

This commit fixes arg-check to compare the old/current commands
including the argument order.

Of course, this change has a side effect; Kbuild will react to the
change of compile option order.  For example, "-DFOO -DBAR" and
"-DBAR -DFOO" should give no difference to the build result, but
false positive should be better than false negative.

I am moving space_escape to the top of Kbuild.include just for a
matter of preference.  In practical terms, space_escape can be
defined after arg-check because arg-check uses "=" flavor, not ":=".
Having said that, collecting convenient variables in one place makes
sense from the point of readability.

Chaining "%%%SPACE%%%" to "_-_SPACE_-_" is also a matter of taste
at this point.  Actually, it can be arbitrary as long as it is an
unlikely used string.  The only problem I see in "%%%SPACE%%%" is
that "%" is a special character in "$(patsubst ...)" context.  This
commit just uses "$(subst ...)" for arg-check, but I am fixing it now
in case we might want to use it in $(patsubst ...) context in the
future.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-10 21:21:14 +02:00
Dirk Gouders
fa64e5f6a3 kconfig/symbol.c: handle choice_values that depend on 'm' symbols
If choices consist of choice_values of type tristate that depend on
symbols set to 'm', those choice_values are not set to 'n' if the
choice is changed from 'm' to 'y' (in which case only one active
choice_value is allowed). Those values are also written to the config
file causing modules to be built when they should not.

The following config can be used to reproduce and examine the problem;
with the frontend of your choice set "Choice 0" and "Choice 1" to 'm',
then set "Tristate Choice" to 'y' and save the configuration:

config modules
	boolean modules
	default y
	option modules

config dependency
	tristate "Dependency"
	default m

choice
	prompt "Tristate Choice"
	default choice0

config choice0
	tristate "Choice 0"

config choice1
	tristate "Choice 1"
	depends on dependency

endchoice

This patch sets tristate choice_values' visibility that depend on
symbols set to 'm' to 'n' if the corresponding choice is set to 'y'.

This makes them disappear from the choice list and will also cause the
choice_values' value set to 'n' in sym_calc_value() and as a result
they are written as "not set" to the resulting .config file.

Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Dirk Gouders <dirk@gouders.net>
Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-10 21:14:27 +02:00
Azriel Samson
962475ac2f builddeb: fix missing headers in linux-headers package
The kernel headers package (linux-headers) doesn't include
header files from other architectures required to build
out-of-tree modules.

For e.g. on ARM64, opcodes.h includes the same file from ARM
which causes the following error:
./arch/arm64/include/asm/opcodes.h:1:43: fatal error:
../../arm/include/asm/opcodes.h: No such file or directory
compilation terminated.

Signed-off-by: Azriel Samson <asamson@codeaurora.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-10 17:44:53 +02:00
Bjørn Mork
697bbc7b83 builddeb: include objtool binary in headers package
"objtool" is required for building external m dules if "Compile-time
stack metadata validation" is enabled.  Otherwise all builds based
on the headers package fail with:

 make[1]: Entering directory '/usr/src/linux-headers-4.6.0-rc6'
 make[2]: *** No rule to make target 'tools/objtool/objtool', needed by 'foo.o'.  Stop.
 Makefile:1598: recipe for target 'foo.ko' failed
 make[1]: *** [foo.ko] Error 2
 make[1]: Leaving directory '/usr/src/linux-headers-4.6.0-rc6'

Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-10 17:41:01 +02:00
Nicolas Pitre
a7c65b9729 kbuild: fix adjust_autoksyms.sh for modules that need only one symbol
When only one symbol was listed and therefore the line didn't contain
any space to separate multiple symbols, that symbol got ignored.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-10 17:25:29 +02:00
Nicolas Pitre
f110e0fec8 kbuild: fix ksym_dep_filter when multiple EXPORT_SYMBOL() on the same line
In kernel/cgroup.c there is:

    #define SUBSYS(_x)                                             \
        DEFINE_STATIC_KEY_TRUE(_x ## _cgrp_subsys_enabled_key);    \
        DEFINE_STATIC_KEY_TRUE(_x ## _cgrp_subsys_on_dfl_key);     \
        EXPORT_SYMBOL_GPL(_x ## _cgrp_subsys_enabled_key);         \
        EXPORT_SYMBOL_GPL(_x ## _cgrp_subsys_on_dfl_key);

The expansion of this macro causes multiple EXPORT_SYMBOL_GPL() instances
to appear on the same preprocessor line output, confusing the sed script
expecting only one of them per line.  Unfortunately this can't be fixed
nicely in the sed script as sed's regexp can't do non greedy matching.

Fix this by turning any semicolon into a line break before filtering.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-10 17:24:15 +02:00
Paul Bolle
a466391139 kconfig: add unexpected data itself to warning
If the .config parser runs into unexpected data it emits warnings like:
    .config:6911:warning: unexpected data

Add the unexpected data itself to this warning. That makes it easier to
discover what is actually going wrong:
     .config:6911:warning: unexpected data: CONFOG_CHARGER_TPS65217=m

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-10 17:20:19 +02:00
Greg Kroah-Hartman
725d0123df Merge 4.6-rc7 into char-misc-testing
This resolves a merge issue with drivers/hv/ring_buffer.c

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-09 09:34:49 +02:00
Philipp Zabel
acbef7b766 modpost: fix module autoloading for OF devices with generic compatible property
Since the wildcard at the end of OF module aliases is gone, autoloading
of modules that don't match a device's last (most generic) compatible
value fails.

For example the CODA960 VPU on i.MX6Q has the SoC specific compatible
"fsl,imx6q-vpu" and the generic compatible "cnm,coda960".  Since the
driver currently only works with knowledge about the SoC specific
integration, it doesn't list "cnm,cod960" in the module device table.

This results in the device compatible
"of:NvpuT<NULL>Cfsl,imx6q-vpuCcnm,coda960" not matching the module alias
"of:N*T*Cfsl,imx6q-vpu" anymore, whereas before commit 2f632369ab79
("modpost: don't add a trailing wildcard for OF module aliases") it
matched the module alias "of:N*T*Cfsl,imx6q-vpu*".

This patch adds two module aliases for each compatible, one without the
wildcard and one with "C*" appended.

  $ modinfo coda | grep imx6q
  alias:          of:N*T*Cfsl,imx6q-vpuC*
  alias:          of:N*T*Cfsl,imx6q-vpu

Fixes: 2f632369ab79 ("modpost: don't add a trailing wildcard for OF module aliases")
Link: http://lkml.kernel.org/r/1462203339-15340-1-git-send-email-p.zabel@pengutronix.de
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Javier Martinez Canillas <javier@osg.samsung.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>	[4.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
Andreas Ziegler
38cbfe4fe8 checkkconfigsymbols.py: Fix typo in help message
Fix a typo in the help message for the -d parameter by removing one 'm'.

Signed-off-by: Andreas Ziegler <andreas.ziegler@fau.de>
Acked-by: Valentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-01 14:11:12 -07:00
Nicolas Pitre
366f4856f0 kbuild: adjust ksym_dep_filter for some cmd_* renames
The following renames occurred recently:

  cmd_cc_i_c --> cmd_cpp_i_c
  cmd_as_s_S --> cmd_cpp_s_S

The respective cc_*_c and as_*_S patterns no longer match the above
therefore additional patterns are needed.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-04-27 10:36:38 +02:00
Benjamin Poirier
5bcba792bb localmodconfig: Fix whitespace repeat count after "tristate"
Also recognize standalone "prompt".

Before this patch we incorrectly identified some symbols as not having a
prompt and potentially needing to be selected by something else.

Note that this patch could theoretically change the resulting .config,
causing it to have fewer symbols turned on. However, given the current set
of Kconfig files, this situation does not occur because the symbols newly
added to %prompts are absent from %selects.

Link: http://lkml.kernel.org/r/1461696998-3953-1-git-send-email-bpoirier@suse.com

Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-26 18:35:16 -04:00
Benjamin Poirier
96bab35d1c localmodconfig: Reset certificate paths
When using `make localmodconfig` and friends, if the input config comes
from a kernel that was built in a different environment (for example, the
canonical case of using localmodconfig to trim a distribution kernel
config) the key files for module signature checking will not be available
and should be regenerated or omitted. Otherwise, the user will be faced
with annoying errors when trying to build with the generated .config:

make[1]: *** No rule to make target 'keyring.crt', needed by 'certs/x509_certificate_list'.  Stop.
Makefile:1576: recipe for target 'certs/' failed

Link: http://lkml.kernel.org/r/1461696721-3001-1-git-send-email-bpoirier@suse.com

Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-26 15:48:20 -04:00
Benjamin Poirier
5169192bc1 localmodconfig: Add missing $ to reference a variable
That is clearly what the original intention was. This does not change the
output .config but it prevents some useless processing.

! eq "m" is changed to the simpler eq "y"; symbols with values other than
m|y are not included in %orig_configs.

Link: http://lkml.kernel.org/r/1460333193-16361-3-git-send-email-bpoirier@suse.com

Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-26 10:06:59 -04:00
Benjamin Poirier
a77ed525d0 localmodconfig: Fix parsing of "help" text
Help text may start with "help" or "---help---". This patch fixes
read_kconfig() to recognize the second variant.

This removes useless junk from %depends and %selects. That junk is due to
help text that contains the words "selects" and "depends".

Link: http://lkml.kernel.org/r/1460333193-16361-2-git-send-email-bpoirier@suse.com

Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-26 10:05:01 -04:00
Benjamin Poirier
27b7156886 localmodconfig: Recognize more keywords that end a menu entry
Based on the list in Documentation/kbuild/kconfig-language.txt

This removes junk from %depends because parsing of a menu entry spilled
over to another menu entry.

Link: http://lkml.kernel.org/r/1460333193-16361-1-git-send-email-bpoirier@suse.com

Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-26 10:04:42 -04:00
Benjamin Poirier
296471ad51 localmodconfig: Fix parsing of Kconfig "source" statements
The parameter of Kconfig "source" statements does not need to be quoted.
The current regex causes many kconfig files to be skipped and hence,
dependencies to be missed.

Also fix the whitespace repeat count.

Link: http://lkml.kernel.org/r/1459619722-13695-1-git-send-email-bpoirier@suse.com

Tested-by: Lee, Chun-Yi <jlee@suse.com>
Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-26 09:59:21 -04:00
Michal Marek
b42841b7bb kbuild: Get rid of KBUILD_STR
The compiler can accept -DKBUILD_MODNAME="foo", it's just a matter of
quoting. That way, we reduce the gcc command line a bit.

Signed-off-by: Michal Marek <mmarek@suse.com>
2016-04-20 10:50:06 +02:00
Masahiro Yamada
e0f41e52dd kbuild: rename cmd_as_s_S to cmd_cpp_s_S
This command just preprocesses .S files into .s files, so cmd_cpp_s_S
seems more suitable.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-04-20 10:49:09 +02:00
Masahiro Yamada
23d4384870 kbuild: rename cmd_cc_i_c to cmd_cpp_i_c
This command just preprocesses .c files into .i files, so cmd_cpp_i_c
seems more suitable.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-04-20 10:48:19 +02:00
Jiri Kosina
27c3bffd23 kbuild/mkspec: support 'update-bootloader'-based systems
When uninstalling kernel RPM, we're unconditionally calling
"new-kernel-pkg --remove". This is useless on systems which are based on
'update-bootloader' script instead.

Support update-bootloader removal method as well in case the script is
present; contrary to new-kernel-pkg, this needs to be done in %postun,
otherwise update-bootloader will refuse to remove entry for kernel for
which the binary still exists.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-04-20 10:01:30 +02:00
Wolfram Sang
f931362b38 scripts: coccinelle: remove check to move constants to right
The header mentions this check depends on personal taste. I agree.
Running coccicheck on patches before I apply them, this SmPL produced
enough false positives for me that I'd rather see it removed.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-04-20 09:53:27 +02:00
Vaishali Thakkar
531f50388f Coccinelle: setup_timer: Add space in front of parentheses
Add space in front of the offending parentheses to silent the
parse error for older Coccinelle versions. This makes the rule
usable with all Coccinelle versions.

Reported-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Vaishali Thakkar <vaishali.thakkar@oracle.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Fixes: c5eda8fd10c6 ("Coccinelle: Add api/setup_timer.cocci")
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-04-20 09:50:53 +02:00
Maxim Zhukov
4deaaa4deb scripts: genksyms: fix resource leak
This commit fixed resource leak at func main

Signed-off-by: Maxim Zhukov <mussitantesmortem@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-04-20 09:24:49 +02:00
Greg Kroah-Hartman
5614e77258 Merge 4.6-rc4 into driver-core-next
We want those fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-19 04:28:28 +09:00
Nicolai Stange
5103068eac debugfs, coccinelle: check for obsolete DEFINE_SIMPLE_ATTRIBUTE() usage
In order to protect against file removal races, debugfs files created via
debugfs_create_file() now get wrapped by a struct file_operations at their
opening.

If the original struct file_operations are known to be safe against removal
races by themselves already, the proxy creation may be bypassed by creating
the files through debugfs_create_file_unsafe().

In order to help debugfs users who use the common
  DEFINE_SIMPLE_ATTRIBUTE() + debugfs_create_file()
idiom to transition to removal safe struct file_operations, the helper
macro DEFINE_DEBUGFS_ATTRIBUTE() has been introduced.

Thus, the preferred strategy is to use
  DEFINE_DEBUGFS_ATTRIBUTE() + debugfs_create_file_unsafe()
now.

Introduce a Coccinelle script that searches for
DEFINE_SIMPLE_ATTRIBUTE()-defined struct file_operations handed into
debugfs_create_file(). Suggest to turn these usages into the
  DEFINE_DEBUGFS_ATTRIBUTE() + debugfs_create_file_unsafe()
pattern.

Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Acked-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12 14:14:21 -07:00
Ard Biesheuvel
2d95863999 ARM: 8553/1: kallsyms: remove --page-offset command line option
The --page-offset command line option was only used for ARM, to filter
symbol addresses below CONFIG_PAGE_OFFSET. This is no longer needed, so
remove the functionality altogether.

Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Chris Brandt <chris.brandt@renesas.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-04-07 21:57:16 +01:00
Ard Biesheuvel
d4ffe41819 ARM: 8552/1: kallsyms: remove special lower address limit for CONFIG_ARM
Now that we no longer emit .stubs symbols into a section VMA loaded
at absolute address 0x1000, we can drop the ARM-specific override that
sets a lower limit based on CONFIG_PAGE_OFFSET, below which symbols are
filtered from the kallsyms output.

Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Chris Brandt <chris.brandt@renesas.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-04-07 21:57:15 +01:00
Ard Biesheuvel
b9b74be163 ARM: 8555/1: kallsyms: ignore ARM mode switching veneers
On ARM, the linker may emit veneers to deal with relative branch
instructions that appear too far away from their targets. Since the
second kallsyms pass results in an increase of the kernel size, it may
result in additional veneers to be emitted, potentially affecting the
output of kallsyms itself if these symbols are visible to it, and for
that reason, symbols whose names end in '_veneer' are ignored explicitly.

However, when building Thumb2 kernels, such veneers are named differently
if they also incur a mode switch, and since they are not filtered by
kallsyms, they may cause the build to fail. So filter symbols whose names
end in '_from_arm' or '_from_thumb' as well.

Tested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-04-07 21:57:15 +01:00
Colin Ian King
952cca6a72 ASN.1: fix open failure check on headername
The check for a failed open on headername is incorrectly checking
on the out FILE pointer rather than the hdr. Fix this.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-06 14:06:48 +01:00
Rob Herring
bc553986a2 dtc: turn off dtc unit address warnings by default
The newly added dtc warning to check DT unit-address without reg
property and vice-versa generates lots of warnings. Turn off the check
unless building with W=1 or W=2.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: linux-kbuild@vger.kernel.org
2016-03-31 11:44:16 -05:00
Nicolas Pitre
23121ca2b5 kbuild: create/adjust generated/autoksyms.h
Given the list of exported symbols needed by all modules, we can create
a header file containing preprocessor defines for each of those symbols.
Also, when some symbols are added and/or removed from the list, we can
update the time on the corresponding files used as build dependencies for
those symbols. And finally, if any symbol did change state, the
corresponding source files must be rebuilt.

The insertion or removal of an EXPORT_SYMBOL() entry within a module may
create or remove the need for another exported symbol.  This is why this
operation has to be repeated until the list of needed exported symbols
becomes stable. Only then the final kernel and modules link take place.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
2016-03-29 16:30:57 -04:00
Nicolas Pitre
c1a95fda2a kbuild: add fine grained build dependencies for exported symbols
Like with kconfig options, we now have the ability to compile in and
out individual EXPORT_SYMBOL() declarations based on the content of
include/generated/autoksyms.h.  However we don't want the entire
world to be rebuilt whenever that file is touched.

Let's apply the same build dependency trick used for CONFIG_* symbols
where the time stamp of empty files whose paths matching those symbols
is used to trigger fine grained rebuilds. In our case the key is the
symbol name passed to EXPORT_SYMBOL().

However, unlike config options, we cannot just use fixdep to parse
the source code for EXPORT_SYMBOL(ksym) because several variants exist
and parsing them all in a separate tool, and keeping it in synch, is
not trivially maintainable.  Furthermore, there are variants such as

	EXPORT_SYMBOL_GPL(pci_user_read_config_##size);

that are instanciated via a macro for which we can't easily determine
the actual exported symbol name(s) short of actually running the
preprocessor on them.

Storing the symbol name string in a special ELF section doesn't work
for targets that output assembly or preprocessed source.

So the best way is really to leverage the preprocessor by having it
output actual symbol names anchored by a special sequence that can be
easily filtered out. Then the list of symbols is simply fed to fixdep
to be merged with the other dependencies.

That implies the preprocessor is executed twice for each source file.
A previous attempt relied on a warning pragma for each EXPORT_SYMBOL()
instance that was filtered apart from stderr by the build system with
a sed script during the actual compilation pass. Unfortunately the
preprocessor/compiler diagnostic output isn't stable between versions
and this solution, although more efficient, was deemed too fragile.

Because of the lowercasing performed by fixdep, there might be name
collisions triggering spurious rebuilds for similar symbols. But this
shouldn't be a big issue in practice. (This is the case for CONFIG_*
symbols and I didn't want to be different here, whatever the original
reason for doing so.)

To avoid needless build overhead, the exported symbol name gathering is
performed only when CONFIG_TRIM_UNUSED_KSYMS is selected.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
2016-03-29 16:30:56 -04:00
Nicolas Pitre
e4aca45950 kbuild: de-duplicate fixdep usage
The generation and postprocessing of automatic dependency rules is
duplicated in rule_cc_o_c, rule_as_o_S and if_changed_dep. Since
this is not a trivial one-liner action, it is now abstracted under
cmd_and_fixdep to simplify things and make future changes in this area
easier.

In the rule_cc_o_c and rule_as_o_S cases that means the order of some
commands has been altered, namely fixdep and related file manipulations
are executed earlier, but they didn't depend on those commands that now
execute later.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
2016-03-29 16:30:56 -04:00
Nicolas Pitre
d8329e35cc fixdep: accept extra dependencies on stdin
... and merge them in the list of parsed dependencies.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
2016-03-29 16:19:40 -04:00
Rob Herring
b993734718 scripts/dtc: Update to upstream version 53bf130b1cdd
Sync to upstream dtc commit 53bf130b1cdd ("libfdt: simplify
fdt_node_check_compatible()"). This adds the following commits from
upstream:

53bf130 libfdt: simplify fdt_node_check_compatible()
c9d9121 Warn on node name unit-address presence/absence mismatch
2e53f9d Catch unsigned 32bit overflow when parsing flattened device tree offsets

Signed-off-by: Rob Herring <robh@kernel.org>
2016-03-29 13:29:22 -05:00
Nicolas Pitre
9895c03d48 kbuild: record needed exported symbols for modules
Kernel modules are partially linked object files with some undefined
symbols that are expected to be matched with EXPORT_SYMBOL() entries
from elsewhere.

Each .tmp_versions/*.mod file currently contains two line of text
separated by a newline character. The first line has the actual module
file name while the second line has a list of object files constituting
that module. Those files are parsed by modpost (scripts/mod/sumversion.c),
scripts/Makefile.modpost, scripts/Makefile.modsign, etc.  Only the
modpost utility cares about the second line while the others retrieve
only the first line.

Therefore we can add a third line to record the list of undefined symbols
aka required EXPORT_SYMBOL() entries for each module into that file
without breaking anything. Like for the second line, symbols are separated
by a blank and the list is terminated with a newline character.

To avoid needless build overhead, the undefined symbols extraction is
performed only when CONFIG_TRIM_UNUSED_KSYMS is selected.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
2016-03-29 13:30:54 -04:00
Linus Torvalds
70c5eb8473 Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild misc updates from Michal Marek:
 "The non-critical part of kbuild for v4.6-rc1:

   - coccinelle cleanup and a new patch
   - make tags rule for kprobe helpers
   - make rpm fix to avoid spurious grub2 entries
   - make rpm support for %postun script (Fedora only at the moment)"

* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild/mkspec: clean boot loader configuration on rpm removal
  kbuild/mkspec: fix grub2 installkernel issue
  Coccinelle: Add api/setup_timer.cocci
  coccinelle: bugon: reduce rule applicability
  Coccinelle: pm_runtime: reduce rule applicability
  Coccinelle: array_size: reduce rule applicability
  Coccinelle: reduce rule applicability
  scripts/tags.sh: add regex to map kprobe helpers
  scripts/coccinelle: modernize &
2016-03-24 19:42:50 -07:00
Linus Torvalds
3a1ef0e03e Merge branch 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kconfig updates from Michal Marek:
 "Just two kconfig commits this time:

   - kconfig Makefile fix for make 3.80

   - Fix calculating symbols so that KCONFIG_ALLCONFIG=... does not
     disable CONFIG_MODULES silently"

* 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  unbreak allmodconfig KCONFIG_ALLCONFIG=...
  scripts/kconfig: allow building with make 3.80 again
2016-03-24 19:39:28 -07:00
Linus Torvalds
2162b80fca Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:

 - make dtbs_install fix

 - Error handling fix fixdep and link-vmlinux.sh

 - __UNIQUE_ID fix for clang

 - Fix for if_changed_* to suppress the "is up to date." message

 - The kernel is built with -Werror=incompatible-pointer-types

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild: Add option to turn incompatible pointer check into error
  kbuild: suppress annoying "... is up to date." message
  kbuild: fixdep: Check fstat(2) return value
  scripts/link-vmlinux.sh: force error on kallsyms failure
  Kbuild: provide a __UNIQUE_ID for clang
  dtbsinstall: don't move target directory out of the way
2016-03-24 19:26:47 -07:00
Helge Deller
0de798584b parisc: Use generic extable search and sort routines
Switch to the generic extable search and sort routines which were introduced
with commit a272858 from Ard Biesheuvel. This saves quite some memory in the
vmlinux binary with the 64bit kernel.

Signed-off-by: Helge Deller <deller@gmx.de>
2016-03-23 16:00:46 +01:00
Andrey Ryabinin
dde5cf39d4 ubsan: fix tree-wide -Wmaybe-uninitialized false positives
-fsanitize=* options makes GCC less smart than usual and increase number
of 'maybe-uninitialized' false-positives. So this patch does two things:

 * Add -Wno-maybe-uninitialized to CFLAGS_UBSAN which will disable all
   such warnings for instrumented files.

 * Remove CONFIG_UBSAN_SANITIZE_ALL from all[yes|mod]config builds. So
   the all[yes|mod]config build goes without -fsanitize=* and still with
   -Wmaybe-uninitialized.

Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Jan Kiszka
ad4db3b24a scripts/gdb: account for changes in module data structure
Commit 7523e4dc5057 ("module: use a structure to encapsulate layout.")
factored out the module_layout structure.  Adjust the symbol loader and
the lsmod command to this.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Kieran Bingham <kieran.bingham@linaro.org>
Tested-by: Kieran Bingham <kieran.bingham@linaro.org> (qemu-{ARM,x86})
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: <stable@vger.kernel.org>	[4.4+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Kieran Bingham
72bf92ec29 scripts/gdb: add cmdline reader command
lx-cmdline Report the Linux Commandline used in the current kernel

[jan.kiszka@siemens.com: remove blank line from help output and fix pep8 warning]
Signed-off-by: Kieran Bingham <kieran.bingham@linaro.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Kieran Bingham
2d061d9994 scripts/gdb: add version command
lx-version Report the Linux Version of the current kernel.

Add a command to identify the version specified by the banner in the
debugged kernel.

This lets the user identify the kernel of the running kernel, and will
let later scripts compare the banner of the attached kernel against the
banner in the vmlinux symbols files to verify that the files are
correct.

[jan.kiszka@siemens.com: remove blank line from help output and fix pep8 warning]
Signed-off-by: Kieran Bingham <kieran.bingham@linaro.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Dmitry Vyukov
5c9a8750a6 kernel: add kcov code coverage
kcov provides code coverage collection for coverage-guided fuzzing
(randomized testing).  Coverage-guided fuzzing is a testing technique
that uses coverage feedback to determine new interesting inputs to a
system.  A notable user-space example is AFL
(http://lcamtuf.coredump.cx/afl/).  However, this technique is not
widely used for kernel testing due to missing compiler and kernel
support.

kcov does not aim to collect as much coverage as possible.  It aims to
collect more or less stable coverage that is function of syscall inputs.
To achieve this goal it does not collect coverage in soft/hard
interrupts and instrumentation of some inherently non-deterministic or
non-interesting parts of kernel is disbled (e.g.  scheduler, locking).

Currently there is a single coverage collection mode (tracing), but the
API anticipates additional collection modes.  Initially I also
implemented a second mode which exposes coverage in a fixed-size hash
table of counters (what Quentin used in his original patch).  I've
dropped the second mode for simplicity.

This patch adds the necessary support on kernel side.  The complimentary
compiler support was added in gcc revision 231296.

We've used this support to build syzkaller system call fuzzer, which has
found 90 kernel bugs in just 2 months:

  https://github.com/google/syzkaller/wiki/Found-Bugs

We've also found 30+ bugs in our internal systems with syzkaller.
Another (yet unexplored) direction where kcov coverage would greatly
help is more traditional "blob mutation".  For example, mounting a
random blob as a filesystem, or receiving a random blob over wire.

Why not gcov.  Typical fuzzing loop looks as follows: (1) reset
coverage, (2) execute a bit of code, (3) collect coverage, repeat.  A
typical coverage can be just a dozen of basic blocks (e.g.  an invalid
input).  In such context gcov becomes prohibitively expensive as
reset/collect coverage steps depend on total number of basic
blocks/edges in program (in case of kernel it is about 2M).  Cost of
kcov depends only on number of executed basic blocks/edges.  On top of
that, kernel requires per-thread coverage because there are always
background threads and unrelated processes that also produce coverage.
With inlined gcov instrumentation per-thread coverage is not possible.

kcov exposes kernel PCs and control flow to user-space which is
insecure.  But debugfs should not be mapped as user accessible.

Based on a patch by Quentin Casasnovas.

[akpm@linux-foundation.org: make task_struct.kcov_mode have type `enum kcov_mode']
[akpm@linux-foundation.org: unbreak allmodconfig]
[akpm@linux-foundation.org: follow x86 Makefile layout standards]
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: syzkaller <syzkaller@googlegroups.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Tavis Ormandy <taviso@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Kees Cook <keescook@google.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: David Drysdale <drysdale@google.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Linus Torvalds
26660a4046 Merge branch 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull 'objtool' stack frame validation from Ingo Molnar:
 "This tree adds a new kernel build-time object file validation feature
  (ONFIG_STACK_VALIDATION=y): kernel stack frame correctness validation.
  It was written by and is maintained by Josh Poimboeuf.

  The motivation: there's a category of hard to find kernel bugs, most
  of them in assembly code (but also occasionally in C code), that
  degrades the quality of kernel stack dumps/backtraces.  These bugs are
  hard to detect at the source code level.  Such bugs result in
  incorrect/incomplete backtraces most of time - but can also in some
  rare cases result in crashes or other undefined behavior.

  The build time correctness checking is done via the new 'objtool'
  user-space utility that was written for this purpose and which is
  hosted in the kernel repository in tools/objtool/.  The tool's (very
  simple) UI and source code design is shaped after Git and perf and
  shares quite a bit of infrastructure with tools/perf (which tooling
  infrastructure sharing effort got merged via perf and is already
  upstream).  Objtool follows the well-known kernel coding style.

  Objtool does not try to check .c or .S files, it instead analyzes the
  resulting .o generated machine code from first principles: it decodes
  the instruction stream and interprets it.  (Right now objtool supports
  the x86-64 architecture.)

  From tools/objtool/Documentation/stack-validation.txt:

   "The kernel CONFIG_STACK_VALIDATION option enables a host tool named
    objtool which runs at compile time.  It has a "check" subcommand
    which analyzes every .o file and ensures the validity of its stack
    metadata.  It enforces a set of rules on asm code and C inline
    assembly code so that stack traces can be reliable.

    Currently it only checks frame pointer usage, but there are plans to
    add CFI validation for C files and CFI generation for asm files.

    For each function, it recursively follows all possible code paths
    and validates the correct frame pointer state at each instruction.

    It also follows code paths involving special sections, like
    .altinstructions, __jump_table, and __ex_table, which can add
    alternative execution paths to a given instruction (or set of
    instructions).  Similarly, it knows how to follow switch statements,
    for which gcc sometimes uses jump tables."

  When this new kernel option is enabled (it's disabled by default), the
  tool, if it finds any suspicious assembly code pattern, outputs
  warnings in compiler warning format:

    warning: objtool: rtlwifi_rate_mapping()+0x2e7: frame pointer state mismatch
    warning: objtool: cik_tiling_mode_table_init()+0x6ce: call without frame pointer save/setup
    warning: objtool:__schedule()+0x3c0: duplicate frame pointer save
    warning: objtool:__schedule()+0x3fd: sibling call from callable instruction with changed frame pointer

  ... so that scripts that pick up compiler warnings will notice them.
  All known warnings triggered by the tool are fixed by the tree, most
  of the commits in fact prepare the kernel to be warning-free.  Most of
  them are bugfixes or cleanups that stand on their own, but there are
  also some annotations of 'special' stack frames for justified cases
  such entries to JIT-ed code (BPF) or really special boot time code.

  There are two other long-term motivations behind this tool as well:

   - To improve the quality and reliability of kernel stack frames, so
     that they can be used for optimized live patching.

   - To create independent infrastructure to check the correctness of
     CFI stack frames at build time.  CFI debuginfo is notoriously
     unreliable and we cannot use it in the kernel as-is without extra
     checking done both on the kernel side and on the build side.

  The quality of kernel stack frames matters to debuggability as well,
  so IMO we can merge this without having to consider the live patching
  or CFI debuginfo angle"

* 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
  objtool: Only print one warning per function
  objtool: Add several performance improvements
  tools: Copy hashtable.h into tools directory
  objtool: Fix false positive warnings for functions with multiple switch statements
  objtool: Rename some variables and functions
  objtool: Remove superflous INIT_LIST_HEAD
  objtool: Add helper macros for traversing instructions
  objtool: Fix false positive warnings related to sibling calls
  objtool: Compile with debugging symbols
  objtool: Detect infinite recursion
  objtool: Prevent infinite recursion in noreturn detection
  objtool: Detect and warn if libelf is missing and don't break the build
  tools: Support relative directory path for 'O='
  objtool: Support CROSS_COMPILE
  x86/asm/decoder: Use explicitly signed chars
  objtool: Enable stack metadata validation on 64-bit x86
  objtool: Add CONFIG_STACK_VALIDATION option
  objtool: Add tool to perform compile-time stack metadata validation
  x86/kprobes: Mark kretprobe_trampoline() stack frame as non-standard
  sched: Always inline context_switch()
  ...
2016-03-20 18:23:21 -07:00