Commit Graph

87 Commits

Author SHA1 Message Date
Linus Torvalds
3ef2bc099d DeviceTree for 4.12:
- Fix sparse warnings in drivers/of/.
 
 - Add more overlay unittests.
 
 - Update dtc to v1.4.4-8-g756ffc4f52f6. This adds more checks on dts
 files such as unit-address formatting and stricter character sets for
 node and property names.
 
 - Add a common DT modalias function.
 
 - Move trivial-devices.txt up and out of i2c dir.
 
 - ARM NVIC interrupt controller binding.
 
 - Vendor prefixes for Sensirion, Dioo, Nordic, ROHM.
 
 - Correct some binding file locations.
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Merge tag 'devicetree-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

Pull DeviceTree updates from Rob Herring:

 - fix sparse warnings in drivers/of/

 - add more overlay unittests

 - update dtc to v1.4.4-8-g756ffc4f52f6. This adds more checks on dts
   files such as unit-address formatting and stricter character sets for
   node and property names

 - add a common DT modalias function

 - move trivial-devices.txt up and out of i2c dir

 - ARM NVIC interrupt controller binding

 - vendor prefixes for Sensirion, Dioo, Nordic, ROHM

 - correct some binding file locations

* tag 'devicetree-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (24 commits)
  of: fix sparse warnings in fdt, irq, reserved mem, and resolver code
  of: fix sparse warning in of_pci_range_parser_one
  of: fix sparse warnings in of_find_next_cache_node
  of/unittest: Missing unlocks on error
  of: fix uninitialized variable warning for overlay test
  of: fix unittest build without CONFIG_OF_OVERLAY
  of: Add unit tests for applying overlays
  of: per-file dtc compiler flags
  fpga: region: add missing DT documentation for config complete timeout
  of: Add vendor prefix for ROHM Semiconductor
  of: fix "/cpus" reference leak in of_numa_parse_cpu_nodes()
  of: Add vendor prefix for Nordic Semiconductor
  dt-bindings: arm,nvic: Binding for ARM NVIC interrupt controller on Cortex-M
  dtc: update warning settings for new bus and node/property name checks
  scripts/dtc: Update to upstream version v1.4.4-8-g756ffc4f52f6
  scripts/dtc: automate getting dtc version and log in update script
  of: Add function for generating a DT modalias with a newline
  of: fix of_device_get_modalias returned length when truncating buffers
  Documentation: devicetree: move trivial-devices out of I2C realm
  dt-bindings: add vendor prefix for Dioo
  ..
2017-05-05 19:33:07 -07:00
Frank Rowand
331f741679 of: per-file dtc compiler flags
The dtc compiler version that adds initial support was available
in 4.11-rc1.  Add the ability to set an additional dtc compiler
flag is needed by overlays.

Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2017-04-27 17:23:54 -05:00
Rob Herring
8654cb8d03 dtc: update warning settings for new bus and node/property name checks
dtc gained new warnings checking PCI and simple buses, unit address
formatting, and stricter node and property name checking. Disable the
new dtc warnings by default as there are 1000s. As before, warnings are
enabled with W=1 or W=2. The strict node and property name checks are a
bit subjective, so they are only enabled for W=2.

Signed-off-by: Rob Herring <robh@kernel.org>
2017-03-29 16:49:41 -05:00
Allan, Bruce W
4607ebf04b kbuild: external module build warnings when KBUILD_OUTPUT set and W=1
Commit db547ef190 ("Kbuild: don't add obj tree in additional includes")
causes warnings (-Wmissing-include-dirs) when compiling external modules
with KBUILD_OUTPUT set and W=1.  This is because $src can be an absolute
path to the external module source which when prefixed with -I$(srctree)/
generates an incorrect directory path.

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-03-11 11:25:57 +09:00
Linus Torvalds
d52bd54db8 Merge branch 'akpm' (patches from Andrew)
Merge yet more updates from Andrew Morton:

 - the rest of ocfs2

 - various hotfixes, mainly MM

 - quite a bit of misc stuff - drivers, fork, exec, signals, etc.

 - printk updates

 - firmware

 - checkpatch

 - nilfs2

 - more kexec stuff than usual

 - rapidio updates

 - w1 things

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (111 commits)
  ipc: delete "nr_ipc_ns"
  kcov: allow more fine-grained coverage instrumentation
  init/Kconfig: add clarification for out-of-tree modules
  config: add android config fragments
  init/Kconfig: ban CONFIG_LOCALVERSION_AUTO with allmodconfig
  relay: add global mode support for buffer-only channels
  init: allow blacklisting of module_init functions
  w1:omap_hdq: fix regression
  w1: add helper macro module_w1_family
  w1: remove need for ida and use PLATFORM_DEVID_AUTO
  rapidio/switches: add driver for IDT gen3 switches
  powerpc/fsl_rio: apply changes for RIO spec rev 3
  rapidio: modify for rev.3 specification changes
  rapidio: change inbound window size type to u64
  rapidio/idt_gen2: fix locking warning
  rapidio: fix error handling in mbox request/release functions
  rapidio/tsi721_dma: advance queue processing from transfer submit call
  rapidio/tsi721: add messaging mbox selector parameter
  rapidio/tsi721: add PCIe MRRS override parameter
  rapidio/tsi721_dma: add channel mask and queue size parameters
  ...
2016-08-02 21:08:07 -04:00
Vegard Nossum
a4691deabf kcov: allow more fine-grained coverage instrumentation
For more targeted fuzzing, it's better to disable kernel-wide
instrumentation and instead enable it on a per-subsystem basis.  This
follows the pattern of UBSAN and allows you to compile in the kcov
driver without instrumenting the whole kernel.

To instrument a part of the kernel, you can use either

    # for a single file in the current directory
    KCOV_INSTRUMENT_filename.o := y

or

    # for all the files in the current directory (excluding subdirectories)
    KCOV_INSTRUMENT := y

or

    # (same as above)
    ccflags-y += $(CFLAGS_KCOV)

or

    # for all the files in the current directory (including subdirectories)
    subdir-ccflags-y += $(CFLAGS_KCOV)

Link: http://lkml.kernel.org/r/1464008380-11405-1-git-send-email-vegard.nossum@oracle.com
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02 19:35:43 -04:00
Arnd Bergmann
db547ef190 Kbuild: don't add obj tree in additional includes
When building with separate object directories and driver specific
Makefiles that add additional header include paths, Kbuild adjusts
the gcc flags so that we include both the directory in the source
tree and in the object tree.

However, due to another bug I fixed earlier, this did not actually
include the correct directory in the object tree, so we know that
we only really need the source tree here. Also, including the
object tree sometimes causes warnings about nonexisting directories
when the include path only exists in the source.

This changes the logic to only emit the -I argument for the srctree,
not for objects. We still need both $(srctree)/$(src) and $(obj)
though, so I'm adding them manually.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-07-18 21:31:35 +02:00
Linus Torvalds
5b26fc8824 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:

 - new option CONFIG_TRIM_UNUSED_KSYMS which does a two-pass build and
   unexports symbols which are not used in the current config [Nicolas
   Pitre]

 - several kbuild rule cleanups [Masahiro Yamada]

 - warning option adjustments for gcov etc [Arnd Bergmann]

 - a few more small fixes

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (31 commits)
  kbuild: move -Wunused-const-variable to W=1 warning level
  kbuild: fix if_change and friends to consider argument order
  kbuild: fix adjust_autoksyms.sh for modules that need only one symbol
  kbuild: fix ksym_dep_filter when multiple EXPORT_SYMBOL() on the same line
  gcov: disable -Wmaybe-uninitialized warning
  gcov: disable tree-loop-im to reduce stack usage
  gcov: disable for COMPILE_TEST
  Kbuild: disable 'maybe-uninitialized' warning for CONFIG_PROFILE_ALL_BRANCHES
  Kbuild: change CC_OPTIMIZE_FOR_SIZE definition
  kbuild: forbid kernel directory to contain spaces and colons
  kbuild: adjust ksym_dep_filter for some cmd_* renames
  kbuild: Fix dependencies for final vmlinux link
  kbuild: better abstract vmlinux sequential prerequisites
  kbuild: fix call to adjust_autoksyms.sh when output directory specified
  kbuild: Get rid of KBUILD_STR
  kbuild: rename cmd_as_s_S to cmd_cpp_s_S
  kbuild: rename cmd_cc_i_c to cmd_cpp_i_c
  kbuild: drop redundant "PHONY += FORCE"
  kbuild: delete unnecessary "@:"
  kbuild: mark help target as PHONY
  ...
2016-05-26 22:01:22 -07:00
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
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
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
Rob Herring
6b22b3d161 kbuild: Allow using host dtc instead of kernel's copy
Development of dtc happens in its own upstream repository, but testing
dtc changes against the kernel tree is useful. Change dtc to a variable
that users can override.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: linux-kbuild@vger.kernel.org
2016-02-23 10:23:55 -06:00
Andrey Ryabinin
c6d308534a UBSAN: run-time undefined behavior sanity checker
UBSAN uses compile-time instrumentation to catch undefined behavior
(UB).  Compiler inserts code that perform certain kinds of checks before
operations that could cause UB.  If check fails (i.e.  UB detected)
__ubsan_handle_* function called to print error message.

So the most of the work is done by compiler.  This patch just implements
ubsan handlers printing errors.

GCC has this capability since 4.9.x [1] (see -fsanitize=undefined
option and its suboptions).
However GCC 5.x has more checkers implemented [2].
Article [3] has a bit more details about UBSAN in the GCC.

[1] - https://gcc.gnu.org/onlinedocs/gcc-4.9.0/gcc/Debugging-Options.html
[2] - https://gcc.gnu.org/onlinedocs/gcc/Debugging-Options.html
[3] - http://developerblog.redhat.com/2014/10/16/gcc-undefined-behavior-sanitizer-ubsan/

Issues which UBSAN has found thus far are:

Found bugs:

 * out-of-bounds access - 97840cb67f ("netfilter: nfnetlink: fix
   insufficient validation in nfnetlink_bind")

undefined shifts:

 * d48458d4a7 ("jbd2: use a better hash function for the revoke
   table")

 * 10632008b9 ("clockevents: Prevent shift out of bounds")

 * 'x << -1' shift in ext4 -
   http://lkml.kernel.org/r/<5444EF21.8020501@samsung.com>

 * undefined rol32(0) -
   http://lkml.kernel.org/r/<1449198241-20654-1-git-send-email-sasha.levin@oracle.com>

 * undefined dirty_ratelimit calculation -
   http://lkml.kernel.org/r/<566594E2.3050306@odin.com>

 * undefined roundown_pow_of_two(0) -
   http://lkml.kernel.org/r/<1449156616-11474-1-git-send-email-sasha.levin@oracle.com>

 * [WONTFIX] undefined shift in __bpf_prog_run -
   http://lkml.kernel.org/r/<CACT4Y+ZxoR3UjLgcNdUm4fECLMx2VdtfrENMtRRCdgHB2n0bJA@mail.gmail.com>

   WONTFIX here because it should be fixed in bpf program, not in kernel.

signed overflows:

 * 32a8df4e0b ("sched: Fix odd values in effective_load()
   calculations")

 * mul overflow in ntp -
   http://lkml.kernel.org/r/<1449175608-1146-1-git-send-email-sasha.levin@oracle.com>

 * incorrect conversion into rtc_time in rtc_time64_to_tm() -
   http://lkml.kernel.org/r/<1449187944-11730-1-git-send-email-sasha.levin@oracle.com>

 * unvalidated timespec in io_getevents() -
   http://lkml.kernel.org/r/<CACT4Y+bBxVYLQ6LtOKrKtnLthqLHcw-BMp3aqP3mjdAvr9FULQ@mail.gmail.com>

 * [NOTABUG] signed overflow in ktime_add_safe() -
   http://lkml.kernel.org/r/<CACT4Y+aJ4muRnWxsUe1CMnA6P8nooO33kwG-c8YZg=0Xc8rJqw@mail.gmail.com>

[akpm@linux-foundation.org: fix unused local warning]
[akpm@linux-foundation.org: fix __int128 build woes]
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yury Gribov <y.gribov@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-20 17:09:18 -08:00
Linus Torvalds
d9569f003c Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:
 - Make <modname>-m in makefiles work like <modname>-y and fix the
   fallout
 - Minor genksyms fix
 - Fix race with make -j install modules_install
 - Move -Wsign-compare from make W=1 to W=2
 - Other minor fixes

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild: Demote 'sign-compare' warning to W=2
  Makefile: revert "Makefile: Document ability to make file.lst and file.S" partially
  kbuild: Do not run modules_install and install in paralel
  genksyms: Handle string literals with spaces in reference files
  fixdep: constify strrcmp arguments
  ath10k: Fix build with CONFIG_THERMAL=m
  Revert "drm: Hack around CONFIG_AGP=m build failures"
  kbuild: Allow to specify composite modules with modname-m
  staging/ad7606: Actually build the interface modules
2016-01-20 09:45:43 -08:00
Heiko Carstens
a7e137eb94 kbuild: add AFLAGS_REMOVE_(basename).o option
It is already possible to remove CFLAGS with the CFLAGS_REMOVE option
that was introduced with commit 656ee82cc8 ("kbuild: create new
CFLAGS_REMOVE_(basename).o option").  However it is not possible to
remove AFLAGS for assembler files.

So this patch just adds the AFLAGS_REMOVE option which works the same
like CFLAGS_REMOVE.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Michal Marek <mmarek@suse.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-12-18 14:59:25 +01:00
Michal Marek
cf4f21938e kbuild: Allow to specify composite modules with modname-m
This allows to write

  drm-$(CONFIG_AGP) += drm_agpsupport.o

without having to handle CONFIG_AGP=y vs. CONFIG_AGP=m. Only support
this syntax for modules, since built-in code depending on something
modular cannot work and init/Makefile actually relies on the current
semantics. There are a few drivers which adapted to the current
semantics out of necessity; these are fixed to also work when the
respective subsystem is modular.

Acked-by: Peter Chen <peter.chen@freescale.com> [chipidea]
Signed-off-by: Michal Marek <mmarek@suse.com>
2015-11-25 11:23:25 +01:00
Nathan Rossi
77479b38e2 kbuild: Create directory for target DTB
When building specific DTBs out of the kernel tree the vendor subdirs
(boot/dts/<vendor>) are not created, ensure that they are before
building the DTB.

Signed-off-by: Nathan Rossi <nathan.rossi@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2015-04-03 13:52:28 -07:00
Andrey Ryabinin
0b24becc81 kasan: add kernel address sanitizer infrastructure
Kernel Address sanitizer (KASan) is a dynamic memory error detector.  It
provides fast and comprehensive solution for finding use-after-free and
out-of-bounds bugs.

KASAN uses compile-time instrumentation for checking every memory access,
therefore GCC > v4.9.2 required.  v4.9.2 almost works, but has issues with
putting symbol aliases into the wrong section, which breaks kasan
instrumentation of globals.

This patch only adds infrastructure for kernel address sanitizer.  It's
not available for use yet.  The idea and some code was borrowed from [1].

Basic idea:

The main idea of KASAN is to use shadow memory to record whether each byte
of memory is safe to access or not, and use compiler's instrumentation to
check the shadow memory on each memory access.

Address sanitizer uses 1/8 of the memory addressable in kernel for shadow
memory and uses direct mapping with a scale and offset to translate a
memory address to its corresponding shadow address.

Here is function to translate address to corresponding shadow address:

     unsigned long kasan_mem_to_shadow(unsigned long addr)
     {
                return (addr >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET;
     }

where KASAN_SHADOW_SCALE_SHIFT = 3.

So for every 8 bytes there is one corresponding byte of shadow memory.
The following encoding used for each shadow byte: 0 means that all 8 bytes
of the corresponding memory region are valid for access; k (1 <= k <= 7)
means that the first k bytes are valid for access, and other (8 - k) bytes
are not; Any negative value indicates that the entire 8-bytes are
inaccessible.  Different negative values used to distinguish between
different kinds of inaccessible memory (redzones, freed memory) (see
mm/kasan/kasan.h).

To be able to detect accesses to bad memory we need a special compiler.
Such compiler inserts a specific function calls (__asan_load*(addr),
__asan_store*(addr)) before each memory access of size 1, 2, 4, 8 or 16.

These functions check whether memory region is valid to access or not by
checking corresponding shadow memory.  If access is not valid an error
printed.

Historical background of the address sanitizer from Dmitry Vyukov:

	"We've developed the set of tools, AddressSanitizer (Asan),
	ThreadSanitizer and MemorySanitizer, for user space. We actively use
	them for testing inside of Google (continuous testing, fuzzing,
	running prod services). To date the tools have found more than 10'000
	scary bugs in Chromium, Google internal codebase and various
	open-source projects (Firefox, OpenSSL, gcc, clang, ffmpeg, MySQL and
	lots of others): [2] [3] [4].
	The tools are part of both gcc and clang compilers.

	We have not yet done massive testing under the Kernel AddressSanitizer
	(it's kind of chicken and egg problem, you need it to be upstream to
	start applying it extensively). To date it has found about 50 bugs.
	Bugs that we've found in upstream kernel are listed in [5].
	We've also found ~20 bugs in out internal version of the kernel. Also
	people from Samsung and Oracle have found some.

	[...]

	As others noted, the main feature of AddressSanitizer is its
	performance due to inline compiler instrumentation and simple linear
	shadow memory. User-space Asan has ~2x slowdown on computational
	programs and ~2x memory consumption increase. Taking into account that
	kernel usually consumes only small fraction of CPU and memory when
	running real user-space programs, I would expect that kernel Asan will
	have ~10-30% slowdown and similar memory consumption increase (when we
	finish all tuning).

	I agree that Asan can well replace kmemcheck. We have plans to start
	working on Kernel MemorySanitizer that finds uses of unitialized
	memory. Asan+Msan will provide feature-parity with kmemcheck. As
	others noted, Asan will unlikely replace debug slab and pagealloc that
	can be enabled at runtime. Asan uses compiler instrumentation, so even
	if it is disabled, it still incurs visible overheads.

	Asan technology is easily portable to other architectures. Compiler
	instrumentation is fully portable. Runtime has some arch-dependent
	parts like shadow mapping and atomic operation interception. They are
	relatively easy to port."

Comparison with other debugging features:
========================================

KMEMCHECK:

  - KASan can do almost everything that kmemcheck can.  KASan uses
    compile-time instrumentation, which makes it significantly faster than
    kmemcheck.  The only advantage of kmemcheck over KASan is detection of
    uninitialized memory reads.

    Some brief performance testing showed that kasan could be
    x500-x600 times faster than kmemcheck:

$ netperf -l 30
		MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to localhost (127.0.0.1) port 0 AF_INET
		Recv   Send    Send
		Socket Socket  Message  Elapsed
		Size   Size    Size     Time     Throughput
		bytes  bytes   bytes    secs.    10^6bits/sec

no debug:	87380  16384  16384    30.00    41624.72

kasan inline:	87380  16384  16384    30.00    12870.54

kasan outline:	87380  16384  16384    30.00    10586.39

kmemcheck: 	87380  16384  16384    30.03      20.23

  - Also kmemcheck couldn't work on several CPUs.  It always sets
    number of CPUs to 1.  KASan doesn't have such limitation.

DEBUG_PAGEALLOC:
	- KASan is slower than DEBUG_PAGEALLOC, but KASan works on sub-page
	  granularity level, so it able to find more bugs.

SLUB_DEBUG (poisoning, redzones):
	- SLUB_DEBUG has lower overhead than KASan.

	- SLUB_DEBUG in most cases are not able to detect bad reads,
	  KASan able to detect both reads and writes.

	- In some cases (e.g. redzone overwritten) SLUB_DEBUG detect
	  bugs only on allocation/freeing of object. KASan catch
	  bugs right before it will happen, so we always know exact
	  place of first bad read/write.

[1] https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel
[2] https://code.google.com/p/address-sanitizer/wiki/FoundBugs
[3] https://code.google.com/p/thread-sanitizer/wiki/FoundBugs
[4] https://code.google.com/p/memory-sanitizer/wiki/FoundBugs
[5] https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel#Trophies

Based on work by Andrey Konovalov.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Acked-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:40 -08:00
Robert Richter
9fb5e53722 dts, kbuild: Factor out dtbs install rules to Makefile.dtbinst
Move dtbs install rules to Makefile.dtbinst. This change is needed to
implement support for dts vendor subdirs. The change makes Makefiles
easier and smaller as no longer the dtbs_install rule needs to be
defined. Another advantage is that install goals are not encoded in
targets anymore (%.dtb_dtbinst_).

Signed-off-by: Robert Richter <rrichter@cavium.com>
2014-10-21 18:06:58 +02:00
Masahiro Yamada
c8589d1e9e kbuild: handle multi-objs dependency appropriately
The comment in scripts/Makefile.build says as follows:

  We would rather have a list of rules like
        foo.o: $(foo-objs)
  but that's not so easy, so we rather make all composite objects depend
  on the set of all their parts

This commit makes it possible!

For example, assume a Makefile like this

  obj-m = foo.o bar.o
  foo-objs := foo1.o foo2.o
  bar-objs := bar1.o bar2.o

Without this patch, foo.o depends on all of
foo1.o foo2.o bar1.o bar2.o.
It looks funny that foo.o is regenerated when bar1.c is updated.

Now we can handle the dependency of foo.o and bar.o separately.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-08-19 10:26:19 +02:00
Masahiro Yamada
38385f8f01 kbuild: trivial - remove trailing spaces
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-04-30 17:34:32 +02:00
Linus Torvalds
b003d7706a Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
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
2014-04-07 17:52:31 -07:00
Masahiro Yamada
13338935f1 kbuild: move "quote" to Kbuild.include to be consistent
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-03-29 22:03:55 +01:00
Grant Likely
dab2310d9d Linux 3.14-rc5
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Merge tag 'v3.14-rc5' into HEAD

Linux 3.14-rc5
2014-03-04 16:44:10 +08:00
Jason Cooper
f4d4ffc03e kbuild: dtbs_install: new make target
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 rules

Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Rob Herring <robh+dt@kernel.org>
2014-02-20 15:53:39 +00:00
Grant Likely
b5190516b2 of: Move testcase FDT data into drivers/of
The testcase data is usable by any platform. This patch moves it into
the drivers/of directory so it can be included by any architecture.

Using the test cases requires manually adding #include <testcases.dtsi>
to the end of the boards .dtsi file and enabling CONFIG_OF_SELFTEST. Not
pretty though. A useful project would be to make the testcase code
easier to execute.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
2014-02-20 11:52:08 +00:00
Linus Torvalds
cb63fc2662 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:
 - fix for make headers_install argv explosion with too long path
 - scripts/setlocalversion does not call git update-index needlessly
 - fix for the src.rpm produced by make rpm-pkg.  The new make
   image_name can be useful also for other packaging tools.
 - scripts/mod/devicetable-offsets.o is not rebuilt during each make run
 - make modules_install dependency fix
 - scripts/sortextable portability fix
 - fix for kbuild to generate the output directory for all object files
   in subdirs.
 - a couple of minor fixes

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild: create directory for dir/file.o
  tools/include: use stdint types for user-space byteshift headers
  Makefile: Fix install error with make -j option
  Fix a build warning in scripts/mod/file2alias.c
  improve modalias building
  scripts/mod: Spelling s/DEVICEVTABLE/DEVICETABLE/
  kbuild: fix error when building from src rpm
  scripts/setlocalversion on write-protected source tree
  Makefile.lib: align DTB quiet_cmd
  kbuild: fix make headers_install when path is too long
2013-07-10 16:05:40 -07:00
Kyungsik Lee
e76e1fdfa8 lib: add support for LZ4-compressed kernel
Add support for extracting LZ4-compressed kernel images, as well as
LZ4-compressed ramdisk images in the kernel boot process.

Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Florian Fainelli <florian@openwrt.org>
Cc: Yann Collet <yann.collet.73@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:30 -07:00
张忠山
4d47dde47f kbuild: create directory for dir/file.o
When add a obj with dir to obj-y, like this

    obj-y += dir/file.o

The $(obj)/dir not created, this patch fix this.

When try to add a file(which in a subdir) to my board's obj-y, the build
progress crashed.

For example, I use at91rm9200ek board, and in kernel dir run:

  mkdir objtree
  make O=objtree at91rm9200_defconfig
  mkdir arch/arm/mach-at91/dir
  touch arch/arm/mach-at91/dir/file.c

and edit arch/arm/mach-at91/dir/file.c to add some code.
then edit arch/arm/mach-at91/Makefile, change the following line:

  obj-$(CONFIG_MACH_AT91RM9200EK) += board-rm9200ek.o

to:

  obj-$(CONFIG_MACH_AT91RM9200EK) += board-rm9200ek.o dir/file.o

Now build it:

  make O=objtree

Then the error appears:
  ...
  CC      arch/arm/mach-at91/board-rm9200dk.o
  CC      arch/arm/mach-at91/board-rm9200ek.o
  CC      arch/arm/mach-at91/dir/file.o
  linux-2.6/arch/arm/mach-at91/dir/file.c:5:
    fatal error: opening dependency file
    arch/arm/mach-at91/dir/.file.o.d: No such file or directory

Check the objtree:
  LANG=en ls objtree/arch/arm/mach-at91/dir
  ls: cannot access objtree/arch/arm/mach-at91/dir: No such file or directory

It's apparently that the target dir not created for file.o

Check kbuild source code. It seems that kbuild create dirs for that in
$(obj-dirs).  But if the dir need not to create a built-in.o, It should
never in  $(obj-dirs).

So I make this patch to make sure It in  $(obj-dirs)

this bug caused by commit
   f5fb976520

Signed-off-by: 张忠山 <zzs0213@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2013-07-03 22:47:08 +02:00
Ian Campbell
b0a4d8b3cf kbuild: make sure we clean up DTB temporary files
Various temporary files used when building DTB files were not suffixed with
.tmp and therefore were not cleaned up by "make clean".

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
2013-06-13 22:12:13 +01:00
James Hogan
1c00a47e48 Makefile.lib: align DTB quiet_cmd
The unaligned dtb.S filename in make output started to irritate me:
  DTC     arch/metag/boot/dts/skeleton.dtb
  DTB    arch/metag/boot/dts/skeleton.dtb.S
  AS      arch/metag/boot/dts/skeleton.dtb.o
  LD      arch/metag/boot/dts/built-in.o

Add an extra space to quiet_cmd_dt_S_dtb so the dtb.S filename aligns
with all the others.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Dirk Brandewie <dirk.brandewie@gmail.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: trivial@kernel.org
Signed-off-by: Michal Marek <mmarek@suse.cz>
2013-06-13 15:59:39 +02:00
Matthijs Kooijman
ad06156876 kbuild: Don't assume dts files live in arch/*/boot/dts
In commit b40b25ff (kbuild: always run gcc -E on *.dts, remove cmd_dtc_cpp),
dts building was changed to always use the C preprocessor. This meant
that the .dts file passed to dtc is not the original, but the
preprocessed one.

When compiling with a separate build directory (i.e., with O=), this
preprocessed file will not live in the same directory as the original.
When the .dts file includes .dtsi files, dtc will look for them in the
build directory, not in the source directory and compilation will fail.

The commit referenced above tried to fix this by passing arch/*/boot/dts
as an include path to dtc. However, for mips, the .dts files are not in
this directory, so dts compilation on mips breaks for some targets.

Instead of hardcoding this particular include path, this commit just
uses the directory of the .dts file that is being compiled, which
effectively restores the previous behaviour wrt includes. For most .dts
files, this path is just the same as the previous hardcoded
arch/*/boot/dts path.

This was tested on a mips (rt3052) and an arm (bcm2835) target.

Signed-off-by: Matthijs Kooijman <matthijs@stdin.nl>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2013-05-23 10:14:34 +02:00
Linus Torvalds
f8ce1faf55 We get rid of the general module prefix confusion with a binary config option,
fix a remove/insert race which Never Happens, and (my favorite) handle the
 case when we have too many modules for a single commandline.  Seriously,
 the kernel is full, please go away!
 
 Cheers,
 Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull mudule updates from Rusty Russell:
 "We get rid of the general module prefix confusion with a binary config
  option, fix a remove/insert race which Never Happens, and (my
  favorite) handle the case when we have too many modules for a single
  commandline.  Seriously, the kernel is full, please go away!"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  modpost: fix unwanted VMLINUX_SYMBOL_STR expansion
  X.509: Support parse long form of length octets in Authority Key Identifier
  module: don't unlink the module until we've removed all exposure.
  kernel: kallsyms: memory override issue, need check destination buffer length
  MODSIGN: do not send garbage to stderr when enabling modules signature
  modpost: handle huge numbers of modules.
  modpost: add -T option to read module names from file/stdin.
  modpost: minor cleanup.
  genksyms: pass symbol-prefix instead of arch
  module: fix symbol versioning with symbol prefixes
  CONFIG_SYMBOL_PREFIX: cleanup.
2013-05-05 10:58:06 -07:00
Stephen Warren
b40b25fff8 kbuild: always run gcc -E on *.dts, remove cmd_dtc_cpp
Replace cmd_dtc with cmd_dtc_cpp, and delete the latter.

Previously, a special file extension (.dtsp) was required to trigger
the C pre-processor to run on device tree files. This was ugly. Now that
previous changes have enhanced cmd_dtc_cpp to collect dependency
information from both gcc -E and dtc, we can transparently run the pre-
processor on all device tree files, irrespective of whether they
use /include/ or #include syntax to include *.dtsi.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
2013-04-05 12:23:07 -06:00
Stephen Warren
85f02be8e5 kbuild: cmd_dtc_cpp: extract deps from both gcc -E and dtc
Prior to this change, when compiling *.dts to *.dtb, the dependency
output from dtc would be used, and when compiling *.dtsp to *.dtb, the
dependency output from gcc -E alone would be used, despite dtc also
being invoked (on a temporary file that was guaranteed to have no
dependencies).

With this change, when compiling *.dtsp to *.dtb, the dependency files
from both gcc -E and dtc are used. This will allow cmd_dtc_cpp to
replace cmd_dtc in a future change. In turn, that will allow the C pre-
processor to be run transparently on *.dts, without the need to a
separate rule or file extension to trigger it.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
2013-04-05 12:23:04 -06:00
Stephen Warren
c58299aa87 kbuild: create an "include chroot" for DT bindings
The recent dtc+cpp support allows header files and C pre-processor
defines/macros to be used when compiling device tree files. These
headers will typically define various constants that are part of the
device tree bindings.

The original patch which set up the dtc+cpp include path only considered
using those headers from device tree files. However, most are also
useful for kernel code which needs to interpret the device tree.

In both the DT files and the kernel, I'd like to include the DT-related
headers in the same way, for example, <dt-bindings/gpio/tegra-gpio.h>.
That will simplify any text which discusses the DT header locations.

Creating a <dt-bindings/> for kernel source to use is as simple as
placing files into include/dt-bindings/.

However, when compiling DT files, the include path should be restricted
so that only the dt-bindings path is available; arbitrary kernel headers
shouldn't be exposed. For this reason, create a specific include
directory for use by dtc+cpp, and symlink dt-bindings from there to the
actual location of include/dt-bindings/. For want of a better location,
place this "include chroot" into the existing dts/ directory.

arch/*/boot/dts/include/dt-bindings -> ../../../../../include/dt-bindings

Some headers used by device tree files may not be useful to the kernel;
they may be used simply to aid in constructing the DT file (e.g. macros
to create a node), but not define any information that the kernel needs
to share. These may be placed directly into arch/*/boot/dts/ along with
the DT files themselves.

Acked-by: Michal Marek <mmarek@suse.cz>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-04-05 12:22:32 -06:00
Rusty Russell
b92021b09d CONFIG_SYMBOL_PREFIX: cleanup.
We have CONFIG_SYMBOL_PREFIX, which three archs define to the string
"_".  But Al Viro broke this in "consolidate cond_syscall and
SYSCALL_ALIAS declarations" (in linux-next), and he's not the first to
do so.

Using CONFIG_SYMBOL_PREFIX is awkward, since we usually just want to
prefix it so something.  So various places define helpers which are
defined to nothing if CONFIG_SYMBOL_PREFIX isn't set:

1) include/asm-generic/unistd.h defines __SYMBOL_PREFIX.
2) include/asm-generic/vmlinux.lds.h defines VMLINUX_SYMBOL(sym)
3) include/linux/export.h defines MODULE_SYMBOL_PREFIX.
4) include/linux/kernel.h defines SYMBOL_PREFIX (which differs from #7)
5) kernel/modsign_certificate.S defines ASM_SYMBOL(sym)
6) scripts/modpost.c defines MODULE_SYMBOL_PREFIX
7) scripts/Makefile.lib defines SYMBOL_PREFIX on the commandline if
   CONFIG_SYMBOL_PREFIX is set, so that we have a non-string version
   for pasting.

(arch/h8300/include/asm/linkage.h defines SYMBOL_NAME(), too).

Let's solve this properly:
1) No more generic prefix, just CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX.
2) Make linux/export.h usable from asm.
3) Define VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR().
4) Make everyone use them.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Tested-by: James Hogan <james.hogan@imgtec.com> (metag)
2013-03-15 15:09:43 +10:30
Stephen Warren
e570d7c15a kbuild: limit dtc+cpp include path
Device tree source files may now include header files. The intent is
that those header files define/name constants used as part of the DT
bindings. Currently this feature is open to abuse, since any kernel
header file at all can be included, This could allow device tree files
to become dependant on kernel headers files, and thus make them no
longer OS-independent. This would also prevent separating the device
tree source files from the kernel repository.

Solve this by limiting the cpp include path for device tree files to
separate directories.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-13 10:12:10 +00:00
Stephen Warren
22435f3833 kbuild: create a rule to run the pre-processor on *.dts files
Create cmd_dtc_cpp to run the C pre-processor on *.dts file before
passing them to dtc for final compilation. This allows the use of #define
and #include within the .dts file.

Acked-by: Simon Glass <sjg@chromium.org>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Michal Marek <mmarek@suse.cz>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-08 14:38:07 +00:00
Stephen Warren
90b335fbbc kbuild: centralize .dts->.dtb rule
All architectures that use cmd_dtc do so in almost the same way. Create
a central build rule to avoid duplication. The one difference is that
most current uses of dtc build $(obj)/%.dtb from $(src)/dts/%.dts rather
than building the .dtb in the same directory as the .dts file. This
difference will be eliminated arch-by-arch in future patches.

MIPS is the exception here; it already uses the exact same rule as the
new common rule, so the duplicate is removed in this patch to avoid any
conflict. arch/mips changes courtesy of Ralf Baechle.

Update Documentation/kbuild to remove the explicit call to cmd_dtc from
the example, now that the rule exists in a centralized location.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Olof Johansson <olof@lixom.net>
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: linux@lists.openrisc.net
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: linux-c6x-dev@linux-c6x.org
Cc: Mark Salter <msalter@redhat.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: microblaze-uclinux@itee.uq.edu.au
Cc: Chris Zankel <chris@zankel.net>
Cc: linux-xtensa@linux-xtensa.org
Cc: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2012-11-30 10:52:19 -06:00
Stephen Warren
e339364514 Kbuild: centralize MKIMAGE and cmd_uimage definitions
All ARCHs have the same definition of MKIMAGE. Move it to Makefile.lib
to avoid duplication.

All ARCHs have similar definitions of cmd_uimage. Place a sufficiently
parameterized version in Makefile.lib to avoid duplication.

Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Mike Frysinger <vapier@gentoo.org> [Blackfin]
Tested-by: Michal Simek <monstr@monstr.eu> [Microblaze]
Tested-by: Guan Xuetao <gxt@mprc.pku.edu.cn> [unicore32]
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-03-26 15:49:20 +02:00
Stephen Warren
7c43185138 Kbuild: Use dtc's -d (dependency) option
This hooks dtc into Kbuild's dependency system.

Thus, for example, "make dtbs" will rebuild tegra-harmony.dtb if only
tegra20.dtsi has changed yet tegra-harmony.dts has not. The previous
lack of this feature recently caused me to have very confusing "git
bisect" results.

For ARM, it's obvious what to add to $(targets). I'm not familiar enough
with other architectures to know what to add there. Powerpc appears to
already add various .dtb files into $(targets), but the other archs may
need something added to $(targets) to work.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
[mmarek: Dropped arch/c6x part to avoid merging commits from the middle
of the merge window]
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-01-15 00:04:35 +01:00
Michal Marek
5bb0571bfd kbuild: Fix comment in Makefile.lib
KBUILD_MODNAME is not defined for files that are linked into multiple
modules, and trying to change reality to match documentation would
result in all sorts of trouble. E.g. options for built-in modules would
be called either foo_bar.param, foo.param, or bar.param, depending on
the configuration. So just change the comment.

Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-01-08 21:54:43 +01:00
Peter Foley
58238c8144 kbuild: prevent make from deleting _shipped files
commit 7373f4f (kbuild: add implicit rules for parser generation)
created a implicit rule chain (%.c: %.c_shipped: %.y).
Make considers the _shipped files to be intermediate files which
causes them to be deleted if they didn't exist before make was run.
Mark the _shipped files PRECIOUS to prevent make from deleting them.

Signed-off-by: Peter Foley <pefoley2@verizon.net>
Acked-by: Arnaud Lacombe <lacombar@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-08-31 16:35:56 +02:00
Arnaud Lacombe
991d76c950 kbuild: simplify the %_shipped rule
This is needed to have make(1) correctly link the implicit rules which
generate the _shipped file from the lexer/parser to the final file.

Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
2011-06-09 14:04:39 -04:00
Arnaud Lacombe
7373f4f83c kbuild: add implicit rules for parser generation
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
2011-06-09 14:04:38 -04:00
Michal Marek
6ae9ecb861 kbuild: Call gzip with -n
The timestamps recorded in the .gz files add no value.

Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-04-18 14:24:36 +02:00
Lasse Collin
24fa0402a9 decompressors: add XZ decompressor module
In userspace, the .lzma format has become mostly a legacy file format that
got superseded by the .xz format.  Similarly, LZMA Utils was superseded by
XZ Utils.

These patches add support for XZ decompression into the kernel.  Most of
the code is as is from XZ Embedded <http://tukaani.org/xz/embedded.html>.
It was written for the Linux kernel but is usable in other projects too.

Advantages of XZ over the current LZMA code in the kernel:
  - Nice API that can be used by other kernel modules; it's
    not limited to kernel, initramfs, and initrd decompression.
  - Integrity check support (CRC32)
  - BCJ filters improve compression of executable code on
    certain architectures. These together with LZMA2 can
    produce a few percent smaller kernel or Squashfs images
    than plain LZMA without making the decompression slower.

This patch: Add the main decompression code (xz_dec), testing module
(xz_dec_test), wrapper script (xz_wrap.sh) for the xz command line tool,
and documentation.  The xz_dec module is enough to have a usable XZ
decompressor e.g.  for Squashfs.

Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:24 -08:00
Dirk Brandewie
aab94339cd of: Add support for linking device tree blobs into vmlinux
This patch adds support for linking device tree blob(s) into
vmlinux. Modifies asm-generic/vmlinux.lds.h to add linking
.dtb sections into vmlinux. To maintain compatiblity with the of/fdt
driver code platforms MUST copy the blob to a non-init memory location
before the kernel frees the .init.* sections in the image.

Modifies scripts/Makefile.lib to add a kbuild command to
compile DTS files to device tree blobs and a rule to create objects to
wrap the blobs for linking.

STRUCT_ALIGNMENT is defined in vmlinux.lds.h for use in the rule to
create wrapper objects for the dtb in Makefile.lib.  The
STRUCT_ALIGN() macro in vmlinux.lds.h is modified to use the
STRUCT_ALIGNMENT definition.

The DTB's are placed on 32 byte boundries to allow parsing the blob
with driver/of/fdt.c during early boot without having to copy the blob
to get the structure alignment GCC expects.

A DTB is linked in by adding the DTB object to the list of objects to
be linked into vmlinux in the archtecture specific Makefile using
   obj-y += foo.dtb.o

Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
Acked-by: Michal Marek <mmarek@suse.cz>
[grant.likely@secretlab.ca: cleaned up whitespace inconsistencies]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2010-12-23 14:43:00 -07:00
Linus Torvalds
c9e2a72ff1 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
  initramfs: Fix build break on symbol-prefixed archs
  initramfs: fix initramfs size calculation
  initramfs: generalize initramfs_data.xxx.S variants
  scripts/kallsyms: Enable error messages while hush up unnecessary warnings
  scripts/setlocalversion: update comment
  kbuild: Use a single clean rule for kernel and external modules
  kbuild: Do not run make clean in $(srctree)
  scripts/mod/modpost.c: fix commentary accordingly to last changes
  kbuild: Really don't clean bounds.h and asm-offsets.h
2010-10-28 15:13:55 -07:00