Commit Graph

1063 Commits

Author SHA1 Message Date
Linus Torvalds f22e6e8471 Linux 4.0-rc7 2015-04-06 15:39:45 -07:00
Masahiro Yamada a436bb7b80 kbuild: use relative path more to include Makefile
Prior to this commit, it was impossible to use relative path to
include Makefiles from the top level Makefile because the option
"--include-dir=$(srctree)" becomes effective when Make enters into
sub Makefiles.

To use relative path in any places, this commit moves the option
above the "sub-make" target.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-04-02 16:42:08 +02:00
Linus Torvalds e42391cd04 Linux 4.0-rc6 2015-03-29 15:26:31 -07:00
Masahiro Yamada 4218affdf5 kbuild: remove warning about "make depend"
Enough time has passed since "make depend" was deprecated.
Nobody would be in trouble without this hint.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-03-24 17:37:53 +01:00
Linus Torvalds bc465aa9d0 Linux 4.0-rc5 2015-03-22 16:50:21 -07:00
Linus Torvalds 06e5801b8c Linux 4.0-rc4 2015-03-15 17:38:20 -07:00
Linus Torvalds 9eccca0843 Linux 4.0-rc3 2015-03-08 16:09:09 -07:00
Linus Torvalds 13a7a6ac0a Linux 4.0-rc2 2015-03-03 09:04:59 -08:00
Linus Torvalds c517d838eb Linux 4.0-rc1
.. after extensive statistical analysis of my G+ polling, I've come to
the inescapable conclusion that internet polls are bad.

Big surprise.

But "Hurr durr I'ma sheep" trounced "I like online polls" by a 62-to-38%
margin, in a poll that people weren't even supposed to participate in.
Who can argue with solid numbers like that? 5,796 votes from people who
can't even follow the most basic directions?

In contrast, "v4.0" beat out "v3.20" by a slimmer margin of 56-to-44%,
but with a total of 29,110 votes right now.

Now, arguably, that vote spread is only about 3,200 votes, which is less
than the almost six thousand votes that the "please ignore" poll got, so
it could be considered noise.

But hey, I asked, so I'll honor the votes.
2015-02-22 18:21:14 -08:00
Linus Torvalds 27a22ee4c7 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:

 - several cleanups in kbuild

 - serialize multiple *config targets so that 'make defconfig kvmconfig'
   works

 - The cc-ifversion macro got support for an else-branch

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild,gcov: simplify kernel/gcov/Makefile more
  kbuild: allow cc-ifversion to have the argument for false condition
  kbuild,gcov: simplify kernel/gcov/Makefile
  kbuild,gcov: remove unnecessary workaround
  kbuild: do not add $(call ...) to invoke cc-version or cc-fullversion
  kbuild: fix cc-ifversion macro
  kbuild: drop $(version_h) from MRPROPER_FILES
  kbuild: use mixed-targets when two or more config targets are given
  kbuild: remove redundant line from bounds.h/asm-offsets.h
  kbuild: merge bounds.h and asm-offsets.h rules
  kbuild: Drop support for clean-rule
2015-02-19 10:07:08 -08:00
Jan Kiszka 3ee7b3fa2c scripts/gdb: add infrastructure
This provides the basic infrastructure to load kernel-specific python
helper scripts when debugging the kernel in gdb.

The loading mechanism is based on gdb loading for <objfile>-gdb.py when
opening <objfile>.  Therefore, this places a corresponding link to the
main helper script into the output directory that contains vmlinux.

The main scripts will pull in submodules containing Linux specific gdb
commands and functions.  To avoid polluting the source directory with
compiled python modules, we link to them from the object directory.

Due to gdb.parse_and_eval and string redirection for gdb.execute, we
depend on gdb >= 7.2.

This feature is enabled via CONFIG_GDB_SCRIPTS.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Michal Marek <mmarek@suse.cz>		[kbuild stuff]
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-17 14:34:53 -08:00
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
Linus Torvalds b3d6524ff7 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:

 - The remaining patches for the z13 machine support: kernel build
   option for z13, the cache synonym avoidance, SMT support,
   compare-and-delay for spinloops and the CES5S crypto adapater.

 - The ftrace support for function tracing with the gcc hotpatch option.
   This touches common code Makefiles, Steven is ok with the changes.

 - The hypfs file system gets an extension to access diagnose 0x0c data
   in user space for performance analysis for Linux running under z/VM.

 - The iucv hvc console gets wildcard spport for the user id filtering.

 - The cacheinfo code is converted to use the generic infrastructure.

 - Cleanup and bug fixes.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (42 commits)
  s390/process: free vx save area when releasing tasks
  s390/hypfs: Eliminate hypfs interval
  s390/hypfs: Add diagnose 0c support
  s390/cacheinfo: don't use smp_processor_id() in preemptible context
  s390/zcrypt: fixed domain scanning problem (again)
  s390/smp: increase maximum value of NR_CPUS to 512
  s390/jump label: use different nop instruction
  s390/jump label: add sanity checks
  s390/mm: correct missing space when reporting user process faults
  s390/dasd: cleanup profiling
  s390/dasd: add locking for global_profile access
  s390/ftrace: hotpatch support for function tracing
  ftrace: let notrace function attribute disable hotpatching if necessary
  ftrace: allow architectures to specify ftrace compile options
  s390: reintroduce diag 44 calls for cpu_relax()
  s390/zcrypt: Add support for new crypto express (CEX5S) adapter.
  s390/zcrypt: Number of supported ap domains is not retrievable.
  s390/spinlock: add compare-and-delay to lock wait loops
  s390/tape: remove redundant if statement
  s390/hvc_iucv: add simple wildcard matches to the iucv allow filter
  ...
2015-02-11 17:42:32 -08:00
Linus Torvalds bfa76d4957 Linux 3.19 2015-02-08 18:54:22 -08:00
Linus Torvalds e36f014edf Linux 3.19-rc7 2015-02-01 20:07:21 -08:00
Heiko Carstens c0a80c0c27 ftrace: allow architectures to specify ftrace compile options
If the kernel is compiled with function tracer support the -pg compile option
is passed to gcc to generate extra code into the prologue of each function.

This patch replaces the "open-coded" -pg compile flag with a CC_FLAGS_FTRACE
makefile variable which architectures can override if a different option
should be used for code generation.

Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-01-29 09:19:19 +01:00
Linus Torvalds 26bc420b59 Linux 3.19-rc6 2015-01-25 20:04:41 -08:00
Linus Torvalds ec6f34e5b5 Linux 3.19-rc5 2015-01-18 18:02:20 +12:00
Linus Torvalds eaa27f34e9 linux 3.19-rc4 2015-01-11 12:44:53 -08:00
Michal Marek 90ac086bca Makefile: include arch/*/include/generated/uapi before .../generated
The introduction of the uapi directories in v3.7-rc1 moved some of the
generated headers from arch/*/include/generated to the uapi directory,
keeping the #include directives intact.

This creates a problem when bisecting, because the unversioned files are
not cleaned automatically by git and the compiler might include stale
headers as a result.  Instead of cleaning them in the Makefiles, promote
arch/*/include/generated/uapi in the search path.  Under normal
circumstances, there is no overlap between this uapi subdirectory and
its parent, so the include choices remain the same.  We keep
arch/*/include/generated/uapi in the USERINCLUDE variable so that it is
usable standalone.

Note that we cannot completely swap the order of the uapi and
kernel-only directories, since the headers in include/uapi/asm-generic
are meant to be wrapped by their include/asm-generic counterparts when
building kernel code.

Reported-by: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Reported-by: David Drysdale <dmd@lurklurk.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-01-08 14:24:54 -08:00
Masahiro Yamada c22bd32c66 kbuild: drop $(version_h) from MRPROPER_FILES
Now $(version_h) is include/generated/uapi/linux/version.h.

$(version_h) in MRPROPER_FILES is redundant because it is covered
by include/generated in MRPROPER_DIRS.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-01-08 16:25:54 +01:00
Masahiro Yamada d0d38cd9e8 kbuild: use mixed-targets when two or more config targets are given
"make kvmconfig" expects that the .config has already been created,
but some people might want to create the .config and run kvmconfig
in one shot command, like this:

  $ make defconfig kvmconfig

To make sure this command works correctly even if -j* option is set,
we must handle them one by one.
This commit turns on mixed-targets when $(MAKECMDGOALS) includes
at least one config target and also includes another target.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-01-08 15:05:28 +01:00
Linus Torvalds b1940cd21c Linux 3.19-rc3 2015-01-05 17:05:20 -08:00
Linus Torvalds b7392d2247 Linux 3.19-rc2 2014-12-28 16:49:37 -08:00
Linus Torvalds 97bf6af1f9 Linux 3.19-rc1 2014-12-20 17:08:50 -08:00
Linus Torvalds d08372ca28 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:
 "Here are the kbuild changes for v3.19-rc1:

   - Cleanups and deduplication in the main Makefile and
     scripts/Makefile.*
   - Sort the output of *config targets in make help
   - Old <linux/version.h> is always removed to avoid a surprise during
     bisecting
   - Warning fix in kconfig"

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild: remove redundant -rR flag of hdr-inst
  kbuild: Fix make help-<board series> on powerpc
  kbuild: Automatically remove stale <linux/version.h> file
  kconfig: Fix warning "‘jump’ may be used uninitialized"
  Makefile: sort list of defconfig targets in make help output
  kbuild: Remove duplicate $(cmd) definition in Makefile.clean
  kbuild: collect shorthands into scripts/Kbuild.include
2014-12-20 13:31:14 -08:00
Linus Torvalds b2776bf714 Linux 3.18 2014-12-07 14:21:05 -08:00
Linus Torvalds 009d0431c3 Linux 3.18-rc7 2014-11-30 16:42:27 -08:00
Michal Marek fbae4d585e kbuild: Fix make help-<board series> on powerpc
make ARCH=powerpc help-<board series> should not require a cofigured
source tree. Also, sort the boards in the output.

Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-11-28 16:39:11 +01:00
Michal Marek 223c24a7db kbuild: Automatically remove stale <linux/version.h> file
In 3.7, the file moved from include/linux/ to
include/generated/uapi/linux/. The path in the #include directive
remained the same for compatibility reasons, but this created a problem
when bisecting. Commit 9c8cdb71 (kbuild: unconditionally clobber
include/linux/version.h on distclean) fixes this, provided the user does
make distclean between builds. Better not rely on the user and delete
the stale file each time make is invoked.

Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-11-28 16:39:05 +01:00
Konstantin Khlebnikov a1e7b7bb1a Makefile: sort list of defconfig targets in make help output
Without sorting this list is completely unreadable for ARCH=arm.

Signed-off-by: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-11-28 13:20:06 +01:00
Masahiro Yamada 371fdc77af kbuild: collect shorthands into scripts/Kbuild.include
The shorthand "clean" is defined in both the top Makefile and
scripts/Makefile.clean.  Likewise, the "hdr-inst" is defined in
both the top Makefile and scripts/Makefile.headersinst.

To reduce code duplication, this commit collects them into
scripts/Kbuild.include like the "build" and "modbuiltin" shorthands.
It requires scripts/Makefile.clean to include scripts/Kbuild.include,
but its impact on the performance of "make clean" should be
negligible.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-11-26 14:36:52 +01:00
Linus Torvalds 5d01410fe4 Linux 3.18-rc6 2014-11-23 15:25:20 -08:00
Linus Torvalds fc14f9c127 Linux 3.18-rc5 2014-11-16 16:36:20 -08:00
Kirill A. Shutemov 51b97e354b kernel: use the gnu89 standard explicitly
Sasha Levin reports:
 "gcc5 changes the default standard to c11, which makes kernel build
  unhappy

  Explicitly define the kernel standard to be gnu89 which should keep
  everything working exactly like it was before gcc5"

There are multiple small issues with the new default, but the biggest
issue seems to be that the old - and very useful - GNU extension to
allow a cast in front of an initializer has gone away.

Patch updated by Kirill:
 "I'm pretty sure all gcc versions you can build kernel with supports
  -std=gnu89.  cc-option is redunrant.

  We also need to adjust HOSTCFLAGS otherwise allmodconfig fails for me"

Note by Andrew Pinski:
 "Yes it was reported and both problems relating to this extension has
  been added to gnu99 and gnu11.  Though there are other issues with the
  kernel dealing with extern inline have different semantics between
  gnu89 and gnu99/11"

End result: we may be able to move up to a newer stdc model eventually,
but right now the newer models have some annoying deficiencies, so the
traditional "gnu89" model ends up being the preferred one.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Singed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-11-15 14:29:55 -08:00
Linus Torvalds 206c5f60a3 Linux 3.18-rc4 2014-11-09 14:55:29 -08:00
Linus Torvalds 0df1f2487d Linux 3.18-rc3 2014-11-02 15:01:51 -08:00
Linus Torvalds cac7f24298 Linux 3.18-rc2 2014-10-26 16:48:41 -07:00
Linus Torvalds f114040e3e Linux 3.18-rc1 2014-10-19 18:08:38 -07:00
Linus Torvalds f33a3faa25 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild changes from Michal Marek:
 - fix for handling dependencies of *-objs targets by Masahiro Yamada
 - lots of cleanups in the kbuild machinery, also by Masahiro
 - fixes for the kconfig build to use an UTF-8 capable ncurses library
   if possible and to build on not-so-standard installs
 - some more minor fixes

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild: Do not reference *-n variables in the Makefile
  kbuild: simplify build, clean, modbuiltin shorthands
  kbuild: arm: Do not define "comma" twice
  kbuild: remove obj-n and lib-n handling
  kbuild: remove unnecessary variable initializaions
  kbuild: remove unnecessary "obj- := dummy.o" trick
  kbuild: handle C=... and M=... after entering into build directory
  kbuild: use $(Q) for sub-make target
  kbuild: fake the "Entering directory ..." message more simply
  kconfig/lxdialog: get ncurses CFLAGS with pkg-config
  kconfig: nconfig: fix multi-byte UTF handling
  kconfig: lxdialog: fix spelling
  kbuild: Make scripts executable
  kbuild: remove redundant clean-files from scripts/kconfig/Makefile
  kbuild: refactor script/kconfig/Makefile
  kbuild: handle the dependency of multi-objs hostprogs appropriately
  kbuild: handle multi-objs dependency appropriately
2014-10-14 09:22:26 +02:00
Linus Torvalds b6420ebd4a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/doc
Pull documentation updates from Jiri Kosina:
 "Updates to kernel documentation.

  I took this over (hopefully temporarily) from Randy who was not
  willing to maintain it any longer.  This pile mostly is a relay of
  queue that Randy already had in his tree"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/doc:
  Documentation: fix broken v4l-utils URL
  Documentation: update include path for mpssd
  Documentation: correct parameter error for dma_mapping_error
  MAINTAINERS: update location of linux-doc tree
  Documentation: remove networking/.gitignore
  tools: add more endian.h macros
  Make Documenation depend on headers_install
  Docs: this_cpu_ops: remove redundant add forms
  Documentation: disable vdso_test to avoid breakage with old glibc
  Documentation: update vDSO makefile to build portable examples
  Documentation: update .gitignore files
  Documentation: support glibc versions without htole macros
  v4l2-pci-skeleton: Only build if PCI is available
  Documentation: fix misc. warnings
  Documentation: make functions static to avoid prototype warnings
  Documentation: add makefiles for more targets
  Documentation: use subdir-y to avoid unnecessary built-in.o files
2014-10-07 21:14:57 -04:00
Linus Torvalds bdf428feb2 Nothing major: support for compressing modules, and auto-tainting params.
Cheers,
 Rusty.
 PS.  My virtio-next tree is empty: DaveM took the patches I had.  There might
      be a virtio-rng starvation fix, but so far it's a bit voodoo so I will
      get to that in the next two days or it will wait.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module update from Rusty Russell:
 "Nothing major: support for compressing modules, and auto-tainting
  params.

  PS. My virtio-next tree is empty: DaveM took the patches I had.  There
      might be a virtio-rng starvation fix, but so far it's a bit voodoo
      so I will get to that in the next two days or it will wait"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  moduleparam: Resolve missing-field-initializer warning
  kbuild: handle module compression while running 'make modules_install'.
  modinst: wrap long lines in order to enhance cmd_modules_install
  modsign: lookup lines ending in .ko in .mod files
  modpost: simplify file name generation of *.mod.c files
  modpost: reduce visibility of symbols and constify r/o arrays
  param: check for tainting before calling set op.
  drm/i915: taint the kernel if unsafe module parameters are set
  module: add module_param_unsafe and module_param_named_unsafe
  module: make it possible to have unsafe, tainting module params
  module: rename KERNEL_PARAM_FL_NOARG to avoid confusion
2014-10-07 20:17:38 -04:00
Linus Torvalds bfe01a5ba2 Linux 3.17 2014-10-05 12:23:04 -07:00
Michal Marek 30142230a7 kbuild: Do not reference *-n variables in the Makefile
Kconfig options are either 'y', 'm', or undefined.

Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-10-02 15:31:53 +02:00
Masahiro Yamada 5b2389b45d kbuild: simplify build, clean, modbuiltin shorthands
$(if $(KBUILD_SRC),$(srctree)/) was a useful strategy
to omit a long absolute path for in-source-tree build
prior to commit 890676c65d
(kbuild: Use relative path when building in the source tree).

Now $(srctree) is "." when building in the source tree.
It would not be annoying to add "$(srctree)/" all the time.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-10-02 15:12:41 +02:00
Masahiro Yamada aa55c8e2f7 kbuild: handle C=... and M=... after entering into build directory
This commit avoids processing C=... and M=... twice
when O=... is also given.

Besides, we can also remove KBUILD_EXTMOD="$(KBUILD_EXTMOD)"
in the sub-make target.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Peter Foley <pefoley2@pefoley.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-10-01 22:44:21 +02:00
Masahiro Yamada 745a254322 kbuild: use $(Q) for sub-make target
Since commit 066b7ed955
(kbuild: Do not print the build directory with make -s),
"Q" is defined above the sub-make target.

This commit takes advantage of that and replaces
"$(if $(KBUILD_VERBOSE:1=),@)" with "$(Q)".

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Peter Foley <pefoley2@pefoley.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-10-01 22:44:21 +02:00
Masahiro Yamada 7ff525712a kbuild: fake the "Entering directory ..." message more simply
Commit c2e28dc975
(kbuild: Print the name of the build directory)
added a gimmick to show the "Entering directory ...".

Instead of echoing the hard-coded message (that is, we need to know
the exact message), moving --no-print-directory would be easier.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Peter Foley <pefoley2@pefoley.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-10-01 22:44:21 +02:00
Linus Torvalds fe82dcec64 Linux 3.17-rc7 2014-09-28 14:29:07 -07:00
Peter Foley 8e2faea877 Make Documenation depend on headers_install
Cc: rdunlap@infradead.org
Cc: linux-doc@vger.kernel.org
Cc: sudeep.dutt@intel.com
Cc: nikhil.rao@intel.com
Cc: ashutosh.dixit@intel.com
Cc: akpm@linux-foundation.org
Cc: gregkh@linuxfoundation.org
Signed-off-by: Peter Foley <pefoley2@pefoley.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-09-26 11:03:01 +02:00
Linus Torvalds 0f33be009b Linux 3.17-rc6 2014-09-21 15:43:02 -07:00
Linus Torvalds 9e82bf0141 Linux 3.17-rc5 2014-09-14 17:50:12 -07:00
Linus Torvalds 2ce7598c9a Linux 3.17-rc4 2014-09-07 16:09:43 -07:00
Linus Torvalds 69e273c0b0 Linux 3.17-rc3 2014-08-31 18:23:04 -07:00
Bertrand Jacquin beb50df39e kbuild: handle module compression while running 'make modules_install'.
Since module-init-tools (gzip) and kmod (gzip and xz) support compressed
modules, it could be useful to include a support for compressing modules
right after having them installed. Doing this in kbuild instead of per
distro can permit to make this kind of usage more generic.

This patch add a Kconfig entry to "Enable loadable module support" menu
and let you choose to compress using gzip (default) or xz.

Both gzip and xz does not used any extra -[1-9] option since Andi Kleen
and Rusty Russell prove no gain is made using them. gzip is called with -n
argument to avoid storing original filename inside compressed file, that
way we can save some more bytes.

On a v3.16 kernel, 'make allmodconfig' generated 4680 modules for a
total of 378MB (no strip, no sign, no compress), the following table
shows observed disk space gain based on the allmodconfig .config :

       |           time                |
       +-------------+-----------------+
       | manual .ko  |       make      | size | percent
       | compression | modules_install |      | gain
       +-------------+-----------------+------+--------
  -    |             |     18.61s      | 378M |
  GZIP |   3m16s     |     3m37s       | 102M | 73.41%
  XZ   |   5m22s     |     5m39s       |  77M | 79.83%

The gain for restricted environnement seems to be interesting while
uncompress can be time consuming but happens only while loading a module,
that is generally done only once.

This is fully compatible with signed modules while the signed module is
compressed. module-init-tools or kmod handles decompression
and provide to other layer the uncompressed but signed payload.

Reviewed-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Bertrand Jacquin <beber@meleeweb.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-08-27 21:54:12 +09:30
Linus Torvalds 52addcf9d6 Linux 3.17-rc2 2014-08-25 15:36:20 -07:00
Linus Torvalds 7d1311b93e Linux 3.17-rc1 2014-08-16 10:40:26 -06:00
Linus Torvalds 899552d6e8 Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull misc kbuild updates from Michal Marek:
 "This is the non-critical part of kbuild for 3.17-rc1:

   - make help hint to use make -s with make kernelrelease et al.
   - moved a kbuild document to Documentation/kbuild where it belongs
   - four new Coccinelle scripts, one dropped and one fixed
   - new make kselftest target to run various tests on the kernel"

* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild: kselftest - new make target to build and run kernel selftests
  Coccinelle: Script to replace if and BUG with BUG_ON
  Coccinelle: Script to detect incorrect argument to sizeof
  Coccinelle: Script to use ARRAY_SIZE instead of division of two sizeofs
  Coccinelle: Script to detect cast after memory allocation
  coccinelle/null: solve parse error
  Documentation: headers_install.txt is part of kbuild
  kbuild: make -s should be used with kernelrelease/kernelversion/image_name
2014-08-14 11:14:29 -06:00
Linus Torvalds 3b7b3e6ec5 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:
 - make clean also considers $(extra-m) and $(extra-) to be consistent
 - cleanup and fixes in scripts/Makefile.host
 - allow to override the name of the Python 2 executable with make
   PYTHON=... (only needed for ia64 in practice)
 - option to split debugingo into *.dwo files to save disk space if the
   compiler supports it (CONFIG_DEBUG_INFO_SPLIT)
 - option to use dwarf4 debuginfo if the compiler supports it
   (CONFIG_DEBUG_INFO_DWARF4)
 - fix for disabling certain warnings with clang
 - fix for unneeded rebuild with dash when a command contains
   backslashes

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild: Fix handling of backslashes in *.cmd files
  kbuild, LLVMLinux: Supress warnings unless W=1-3
  Kbuild: Add a option to enable dwarf4 v2
  kbuild: Support split debug info v4
  kbuild: allow to override Python command name
  kbuild: clean-up and bug fix of scripts/Makefile.host
  kbuild: clean up scripts/Makefile.host
  kbuild: drop shared library support from Makefile.host
  kbuild: fix a bug of C++ host program handling
  kbuild: fix a typo in scripts/Makefile.host
  scripts/Makefile.clean: clean also $(extra-m) and $(extra-)
2014-08-14 11:12:46 -06:00
Shuah Khan 5a5da78b3a kbuild: kselftest - new make target to build and run kernel selftests
Add a new make target "kselftest" to enable kernel testing. This
new target builds and runs kernel selftests. Running as root is
recommended for a complete test run as some tests don't run when
run by non-root user. Build, install, and boot kernel before
running kselftest on it.

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-08-07 22:30:01 +02:00
Jiri Kosina 69102311a5 ./Makefile: tell gcc optimizer to never introduce new data races
We have been chasing a memory corruption bug, which turned out to be
caused by very old gcc (4.3.4), which happily turned conditional load
into a non-conditional one, and that broke correctness (the condition
was met only if lock was held) and corrupted memory.

This particular problem with that particular code did not happen when
never gccs were used.  I've brought this up with our gcc folks, as I
wanted to make sure that this can't really happen again, and it turns
out it actually can.

Quoting Martin Jambor <mjambor@suse.cz>:
 "More current GCCs are more careful when it comes to replacing a
  conditional load with a non-conditional one, most notably they check
  that a store happens in each iteration of _a_ loop but they assume
  loops are executed.  They also perform a simple check whether the
  store cannot trap which currently passes only for non-const
  variables.  A simple testcase demonstrating it on an x86_64 is for
  example the following:

  $ cat cond_store.c

  int g_1 = 1;

  int g_2[1024] __attribute__((section ("safe_section"), aligned (4096)));

  int c = 4;

  int __attribute__ ((noinline))
  foo (void)
  {
    int l;
    for (l = 0; (l != 4); l++) {
      if (g_1)
        return l;
      for (g_2[0] = 0; (g_2[0] >= 26); ++g_2[0])
        ;
    }
    return 2;
  }

  int main (int argc, char* argv[])
  {
    if (mprotect (g_2, sizeof(g_2), PROT_READ) == -1)
      {
        int e = errno;
        error (e, e, "mprotect error %i", e);
      }
    foo ();
    __builtin_printf("OK\n");
    return 0;
  }
  /* EOF */
  $ ~/gcc/trunk/inst/bin/gcc cond_store.c -O2 --param allow-store-data-races=0
  $ ./a.out
  OK
  $ ~/gcc/trunk/inst/bin/gcc cond_store.c -O2 --param allow-store-data-races=1
  $ ./a.out
  Segmentation fault

  The testcase fails the same at least with 4.9, 4.8 and 4.7.  Therefore
  I would suggest building kernels with this parameter set to zero. I
  also agree with Jikos that the default should be changed for -O2.  I
  have run most of the SPEC 2k6 CPU benchmarks (gamess and dealII
  failed, at -O2, not sure why) compiled with and without this option
  and did not see any real difference between respective run-times"

Hopefully the default will be changed in newer gccs, but let's force it
for kernel builds so that we are on a safe side even when older gcc are
used.

The code in question was out-of-tree printk-in-NMI (yeah, surprise
suprise, once again) patch written by Petr Mladek, let me quote his
comment from our internal bugzilla:

 "I have spent few days investigating inconsistent state of kernel ring buffer.
  It went out that it was caused by speculative store generated by
  gcc-4.3.4.

  The problem is in assembly generated for make_free_space(). The functions is
  called the following way:

  + vprintk_emit();
      + log = MAIN_LOG; // with logbuf_lock
         or
         log = NMI_LOG; // with nmi_logbuf_lock
         cont_add(log, ...);
          + cont_flush(log, ...);
              + log_store(log, ...);
                    + log_make_free_space(log, ...);

  If called with log = NMI_LOG then only nmi_log_* global variables are safe to
  modify but the generated code does store also into (main_)log_* global
  variables:

  <log_make_free_space>:
         55                      push   %rbp
         89 f6                   mov    %esi,%esi

         48 8b 05 03 99 51 01    mov    0x1519903(%rip),%rax       # ffffffff82620868 <nmi_log_next_id>
         44 8b 1d ec 98 51 01    mov    0x15198ec(%rip),%r11d      # ffffffff82620858 <log_next_idx>
         8b 35 36 60 14 01       mov    0x1146036(%rip),%esi       # ffffffff8224cfa8 <log_buf_len>
         44 8b 35 33 60 14 01    mov    0x1146033(%rip),%r14d      # ffffffff8224cfac <nmi_log_buf_len>
         4c 8b 2d d0 98 51 01    mov    0x15198d0(%rip),%r13       # ffffffff82620850 <log_next_seq>
         4c 8b 25 11 61 14 01    mov    0x1146111(%rip),%r12       # ffffffff8224d098 <log_buf>
         49 89 c2                mov    %rax,%r10
         48 21 c2                and    %rax,%rdx
         48 8b 1d 0c 99 55 01    mov    0x155990c(%rip),%rbx       # ffffffff826608a0 <nmi_log_buf>
         49 c1 ea 20             shr    $0x20,%r10
         48 89 55 d0             mov    %rdx,-0x30(%rbp)
         44 29 de                sub    %r11d,%esi
         45 29 d6                sub    %r10d,%r14d
         4c 8b 0d 97 98 51 01    mov    0x1519897(%rip),%r9	# ffffffff82620840 <log_first_seq>
         eb 7e                   jmp    ffffffff81107029	<log_make_free_space+0xe9>
  [...]
         85 ff                   test   %edi,%edi                  # edi = 1 for NMI_LOG
         4c 89 e8                mov    %r13,%rax
         4c 89 ca                mov    %r9,%rdx
         74 0a                   je     ffffffff8110703d	<log_make_free_space+0xfd>
         8b 15 27 98 51 01       mov    0x1519827(%rip),%edx       # ffffffff82620860 <nmi_log_first_id>
         48 8b 45 d0             mov    -0x30(%rbp),%rax
         48 39 c2                cmp    %rax,%rdx                  # end of loop
         0f 84 da 00 00 00       je     ffffffff81107120 <log_make_free_space+0x1e0>
  [...]
         85 ff                   test   %edi,%edi                  # edi = 1 for NMI_LOG
         4c 89 0d 17 97 51 01    mov    %r9,0x1519717(%rip)        # ffffffff82620840 <log_first_seq>
                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^
                                 KABOOOM
         74 35                   je     ffffffff81107160		 <log_make_free_space+0x220>

  It stores log_first_seq when edi == NMI_LOG. This instructions are used also
  when edi == MAIN_LOG but the store is done speculatively before the condition
  is decided.  It is unsafe because we do not have "logbuf_lock" in NMI context
  and some other process migh modify "log_first_seq" in parallel"

I believe that the best course of action is both

 - building kernel (and anything multi-threaded, I guess) with that
   optimization turned off
 - persuade gcc folks to change the default for future releases

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Cc: Martin Jambor <mjambor@suse.cz>
Cc: Petr Mladek <pmladek@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Marek Polacek <polacek@redhat.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Steven Noonan <steven@uplinklabs.net>
Cc: Richard Biener <richard.guenther@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06 18:01:23 -07:00
Kees Cook 1332429b30 ./Makefile: explain stack-protector-strong CONFIG logic
This adds a hopefully helpful comment above the (seemingly weird) compiler
flag selection logic.

Signed-off-by: Kees Cook <keescook@chromium.org>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Michal Hocko <mhocko@suse.cz>
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>
2014-08-06 18:01:12 -07:00
Behan Webster 26ea6bb1fe kbuild, LLVMLinux: Supress warnings unless W=1-3
clang has more warnings enabled by default. Turn them off unless W is
set. This patch fixes a logic bug where warnings in clang were disabled
when W was set.

Signed-off-by: Behan Webster <behanw@converseincode.com>
Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
Signed-off-by: Mark Charlebois <charlebm@gmail.com>
Cc: bp@alien8.de
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-08-05 15:40:01 +02:00
Linus Torvalds 19583ca584 Linux 3.16 2014-08-03 15:25:02 -07:00
Andi Kleen bfaf2dd350 Kbuild: Add a option to enable dwarf4 v2
I found that a lot of unresolvable variables when using gdb on the
kernel become resolvable when dwarf4 is enabled. So add a Kconfig flag
to enable it.

It definitely increases the debug information size, but on the other
hand this isn't so bad when debug fusion is used.

v2: Use cc-option
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-07-30 22:56:04 +02:00
Andi Kleen 866ced950b kbuild: Support split debug info v4
This is an alternative approach to lower the overhead of debug info
(as we discussed a few days ago)

gcc 4.7+ and newer binutils have a new "split debug info" debug info
model where the debug info is only written once into central ".dwo" files.

This avoids having to copy it around multiple times, from the object
files to the final executable. It lowers the disk space
requirements. In addition it defaults to compressed debug data.

More details here: http://gcc.gnu.org/wiki/DebugFission

This patch adds a new option to enable it. It has to be an option,
because it'll undoubtedly break everyone's debuginfo packaging scheme.
gdb/objdump/etc. all still work, if you have new enough versions.

I don't see big compile wins (maybe a second or two faster or so), but the
object dirs with debuginfo get significantly smaller. My standard kernel
config (slightly bigger than defconfig) shrinks from 2.9G disk space
to 1.1G objdir (with non reduced debuginfo). I presume if you are IO limited
the compile time difference will be larger.

Only problem I've seen so far is that it doesn't play well with older
versions of ccache (apparently fixed, see
https://bugzilla.samba.org/show_bug.cgi?id=10005)

v2: various fixes from Dirk Gouders. Improve commit message slightly.
v3: Fix clean rules and improve Kconfig slightly
v4: Fix merge error in last version (Sam Ravnborg)
    Clarify description that it mainly helps disk size.
Cc: Dirk Gouders <dirk@gouders.net>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-07-30 22:54:52 +02:00
Linus Torvalds 64aa90f26c Linux 3.16-rc7 2014-07-27 12:41:55 -07:00
Linus Torvalds 2062afb4f8 Fix gcc-4.9.0 miscompilation of load_balance() in scheduler
Michel Dänzer and a couple of other people reported inexplicable random
oopses in the scheduler, and the cause turns out to be gcc mis-compiling
the load_balance() function when debugging is enabled.  The gcc bug
apparently goes back to gcc-4.5, but slight optimization changes means
that it now showed up as a problem in 4.9.0 and 4.9.1.

The instruction scheduling problem causes gcc to schedule a spill
operation to before the stack frame has been created, which in turn can
corrupt the spilled value if an interrupt comes in.  There may be other
effects of this bug too, but that's the code generation problem seen in
Michel's case.

This is fixed in current gcc HEAD, but the workaround as suggested by
Markus Trippelsdorf is pretty simple: use -fno-var-tracking-assignments
when compiling the kernel, which disables the gcc code that causes the
problem.  This can result in slightly worse debug information for
variable accesses, but that is infinitely preferable to actual code
generation problems.

Doing this unconditionally (not just for CONFIG_DEBUG_INFO) also allows
non-debug builds to verify that the debug build would be identical: we
can do

    export GCC_COMPARE_DEBUG=1

to make gcc internally verify that the result of the build is
independent of the "-g" flag (it will make the compiler build everything
twice, toggling the debug flag, and compare the results).

Without the "-fno-var-tracking-assignments" option, the build would fail
(even with 4.8.3 that didn't show the actual stack frame bug) with a gcc
compare failure.

See also gcc bugzilla:

  https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61801

Reported-by: Michel Dänzer <michel@daenzer.net>
Suggested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-26 14:52:01 -07:00
Linus Torvalds 9a3c4145af Linux 3.16-rc6 2014-07-20 21:04:16 -07:00
Masahiro Yamada 011bf12547 kbuild: allow to override Python command name
The specification of Python 3 is largely different from that of
Python 2.

For example, arch/ia64/scripts/unwcheck.py seems to be written
in Python 2, not compatible with Python 3.

It is not a good idea to invoke python scripts with the hard-coded
command name 'python'. The command 'python' could possibly be
Python 3 on some systems.
For that case, it is reasonable to allow to override the command name
by giving 'PYTHON=python2' from the command line.

The 'python' in arch/ia64/Makefile should be replaced with '$(PYTHON)'.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: linux-ia64@vger.kernel.org
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-07-18 10:17:58 +02:00
Linus Torvalds 1795cd9b3a Linux 3.16-rc5 2014-07-13 14:04:33 -07:00
Michal Marek 3f1d9a6cec kbuild: make -s should be used with kernelrelease/kernelversion/image_name
If .config has been edited, there will be a silentoldconfig run:

  $ make defconfig
  ...
  $ make kernelrelease
  scripts/kconfig/conf --silentoldconfig Kconfig
  3.16.0-rc1+

Recently, kbuild started to print the name of the build directory when
using O=

  $ make O=build kernelrelease
  make[1]: Entering directory `/dev/shm/mmarek/linux-2.6/build'
  3.16.0-rc1+

Since these targets are often used in scripts, add a hint to use make -s
to the help text.

Suggested-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-07-11 16:11:45 +02:00
Linus Torvalds fe5aa8a65b Merge branch 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild fixes from Michal Marek:
 "Three more fixes for the relative build dir feature:

   - Shut up make -s again
   - Fix for rpm/deb/tar-pkg with O=<subdir>
   - Fix for CONFIG_EXTRA_FIRMWARE"

* 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  firmware: Create directories for external firmware
  kbuild: Fix packaging targets with relative $(srctree)
  kbuild: Do not print the build directory with make -s
2014-07-10 18:40:47 -07:00
Linus Torvalds cd3de83f14 Linux 3.16-rc4 2014-07-06 12:37:51 -07:00
Michal Marek c79624c1a6 kbuild: Fix packaging targets with relative $(srctree)
All other users of Makefile.build set $(obj) to the name of the
subdirectory to build. Do the same for the packaging targets, otherwise
the build fails if $(srctree) is a relative directory:

    $ make O=build tar-pkg
    make[1]: Entering directory `/home/mmarek/linux-2.6/build'
      CHK     include/config/kernel.release
    ../scripts/Makefile.build:44: ../../scripts/package/Makefile: No such file or directory
    make[2]: *** No rule to make target `../../scripts/package/Makefile'.  Stop.

Fixes: 9da0763b ("kbuild: Use relative path when building in a subdir of the source tree")
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-07-04 22:58:55 +02:00
Michal Marek 066b7ed955 kbuild: Do not print the build directory with make -s
Commit c2e28dc9 (kbuild: Print the name of the build directory) prints
the name of the build directory for O= builds, but we should not be
doing this in make -s mode, so that commands like

  make -s O=<dir> kernelrelease

can be used by scripts. This matches the behavior of make itself, where
the -s option implies --no-print-directory.

Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-07-04 14:33:33 +02:00
Linus Torvalds af6f157a4b Merge branch 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild fix from Michal Marek:
 "There is one more fix for the relative paths series from -rc1: Print
  the path to the build directory at the start of the build, so that
  editors and IDEs can match the relative paths to source files"

* 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild: Print the name of the build directory
2014-07-03 18:34:00 -07:00
Michal Marek c2e28dc975 kbuild: Print the name of the build directory
With commit 9da0763b (kbuild: Use relative path when building in a
subdir of the source tree), the compiler messages include relative
paths. These are however relative to the build directory, not the
directory where make was started. Print the "Entering directory ..."
message once, so that IDEs/editors can find the source files.

Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-07-03 15:25:11 +02:00
Linus Torvalds 4c834452aa Linux 3.16-rc3 2014-06-29 14:11:36 -07:00
Linus Torvalds a497c3ba1d Linux 3.16-rc2 2014-06-21 19:02:54 -10:00
Linus Torvalds 7171511eae Linux 3.16-rc1 2014-06-15 17:45:28 -10:00
Linus Torvalds 1700ff823b Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:
 "Kbuild changes for v3.16-rc1:

   - cross-compilation fix so that cc-option is testing the right
     compiler
   - Fix for make defconfig all
   - Using relative paths to the object and source directory where
     possible, plus fixes for the fallout of the change
   - several cleanups in the Makefiles and scripts

  The powerpc fix is from today, because it was only discovered
  recently.  The rest has been in linux-next for some time"

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  powerpc: Avoid circular dependency with zImage.%
  kbuild: create include/config directory in scripts/kconfig/Makefile
  kbuild: do not create include/linux directory
  Makefile: Fix unrecognized cross-compiler command line options
  kbuild: do not add "selinux" to subdir- twice
  um: Fix for relative objtree when generating x86 headers
  kbuild: Use relative path when building in a subdir of the source tree
  kbuild: Use relative path when building in the source tree
  kbuild: Use relative path for $(objtree)
  firmware: Use $(quote) in the Makefile
  firmware: Simplify directory creation
  kbuild: trivial - fix comment block indent
  kbuild: trivial - remove trailing spaces
  kbuild: support simultaneous "make %config" and "make all"
  kbuild: move extra gcc checks to scripts/Makefile.extrawarn
2014-06-12 21:23:38 -07:00
Masahiro Yamada 9815594a78 kbuild: create include/config directory in scripts/kconfig/Makefile
The directory include/config is used only for
silentoldconfig, localmodconfig, localyesconfig.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-06-10 00:20:20 +02:00
Masahiro Yamada 356db564fb kbuild: do not create include/linux directory
There are no generated files under include/linux directory.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-06-10 00:20:12 +02:00
Geert Uytterhoeven a1c48bb160 Makefile: Fix unrecognized cross-compiler command line options
On architectures that setup CROSS_COMPILE in their arch/*/Makefile
(arc, blackfin, m68k, mips, parisc, score, sh, tile, unicore32, xtensa),
cc-option and cc-disable-warning may check against the wrong compiler,
causing errors like

    cc1: error: unrecognized command line option "-Wno-maybe-uninitialized"

if the host gcc supports a compiler option, while the cross compiler
doesn't support that option.

Move all logic using cc-option or cc-disable-warning below the inclusion
of the arch's Makefile to fix this.

Introduced by
  - commit e74fc973b6 ("Turn off
    -Wmaybe-uninitialized when building with -Os"),
  - commit 61163efae0 ("kbuild: LLVMLinux:
    Add Kbuild support for building kernel with Clang").

As -Wno-maybe-uninitialized requires a quite recent gcc (gcc 4.6.3 on
Ubuntu 12.04 LTS doesn't support it), this only showed up recently (gcc
4.8.2 on Ubuntu 14.04 LTS does support it).

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-06-09 23:28:07 +02:00
Linus Torvalds b20dcab9d4 LLVMLinux patches for v3.16
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Merge tag 'llvmlinux-for-v3.16' of git://git.linuxfoundation.org/llvmlinux/kernel

Pull LLVM patches from Behan Webster:
 "Next set of patches to support compiling the kernel with clang.
  They've been soaking in linux-next since the last merge window.

  More still in the works for the next merge window..."

* tag 'llvmlinux-for-v3.16' of git://git.linuxfoundation.org/llvmlinux/kernel:
  arm, unwind, LLVMLinux: Enable clang to be used for unwinding the stack
  ARM: LLVMLinux: Change "extern inline" to "static inline" in glue-cache.h
  all: LLVMLinux: Change DWARF flag to support gcc and clang
  net: netfilter: LLVMLinux: vlais-netfilter
  crypto: LLVMLinux: aligned-attribute.patch
2014-06-08 12:27:44 -07:00
Linus Torvalds 1860e37987 Linux 3.15 2014-06-08 11:19:54 -07:00
Behan Webster 2288328ce9 all: LLVMLinux: Change DWARF flag to support gcc and clang
Both gcc (well, actually gnu as) and clang support the "-Wa,-gdwarf-2" option
(though clang does not support "-Wa,--gdwarf-2"). Since these flags are equivalent
in meaning, this patch uses the one which is better supported across compilers.

Signed-off-by: Behan Webster <behanw@converseincode.com>
2014-06-07 11:44:39 -07:00
Linus Torvalds fad01e866a Linux 3.15-rc8 2014-06-01 19:12:24 -07:00
Linus Torvalds c7208164e6 Linux 3.15-rc7 2014-05-25 16:06:00 -07:00
Linus Torvalds 4b660a7f5c Linux 3.15-rc6 2014-05-22 06:42:02 +09:00
Michal Marek 9da0763bdd kbuild: Use relative path when building in a subdir of the source tree
When doing make O=<subdir>, use '..' to refer to the source tree. This
allows for more readable compiler messages, and, more importantly, it
sets the VPATH to '..', so filenames in WARN_ON() etc. will be shorter.

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-05-14 22:43:05 +02:00
Michal Marek 890676c65d kbuild: Use relative path when building in the source tree
When not using O=, $(srctree) refers to the same directory as
$(objtree), so we can set it to '.' as well. This makes the default
include path more compact and results in more readable messages from the
compiler. The only case where we need the absolute path is when creating
the 'source' symlink in /lib/modules.

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-05-14 22:43:05 +02:00
Michal Marek 7e1c04779e kbuild: Use relative path for $(objtree)
The main Makefile sets its working directory to the object tree and
never changes it again. Therefore, we can use '.' instead of the
absolute path. The only case where we need the absolute path is when
creating the 'build' symlink in /lib/modules.

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-05-14 22:43:04 +02:00
Linus Torvalds d6d211db37 Linux 3.15-rc5 2014-05-09 13:10:52 -07:00
Linus Torvalds 89ca3b8819 Linux 3.15-rc4 2014-05-04 18:14:42 -07:00
Masahiro Yamada 3fbb43df98 kbuild: trivial - fix comment block indent
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-04-30 17:34:35 +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
Masahiro Yamada 9319f4539c kbuild: support simultaneous "make %config" and "make all"
Kbuild is supposed to support mixed targets. (%config and build targets)

But "make all" did nothing if it was run with configuration targets.
For example,

  $ LANG=C make defconfig all
    HOSTCC  scripts/basic/fixdep
    HOSTCC  scripts/kconfig/conf.o
    SHIPPED scripts/kconfig/zconf.tab.c
    SHIPPED scripts/kconfig/zconf.lex.c
    SHIPPED scripts/kconfig/zconf.hash.c
    HOSTCC  scripts/kconfig/zconf.tab.o
    HOSTLD  scripts/kconfig/conf
  *** Default configuration is based on 'x86_64_defconfig'
  #
  # configuration written to .config
  #
  make: Nothing to be done for `all'.

This commits allows "make %config all" and makes sure
mixed targets are built one by one in the given order.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Michal Marek <mmarek@suse.cz>
CC: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-04-30 16:45:16 +02:00
Linus Torvalds d1db0eea85 Linux 3.15-rc3 2014-04-27 19:29:27 -07:00