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948 commits

Author SHA1 Message Date
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
Linus Torvalds
19583ca584 Linux 3.16 2014-08-03 15:25:02 -07:00
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
Linus Torvalds
1795cd9b3a Linux 3.16-rc5 2014-07-13 14:04:33 -07:00
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
Linus Torvalds
a798c10faf Linux 3.15-rc2 2014-04-20 11:08:50 -07:00
Masahiro Yamada
a86fe35373 kbuild: move extra gcc checks to scripts/Makefile.extrawarn
W=... provides extra gcc checks.

Having such code in scripts/Makefile.build results in the same flags
being added to KBUILD_CFLAGS multiple times becuase
scripts/Makefile.build is invoked every time Kbuild descends into
the subdirectories.

Since the top Makefile is already too cluttered, this commit moves
all of extra gcc check stuff to a new file scripts/Makefile.extrawarn,
which is included from the top Makefile.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
CC: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-04-16 23:28:41 +02:00
Linus Torvalds
c9eaa447e7 Linux 3.15-rc1 2014-04-13 14:18:35 -07:00
Linus Torvalds
321d03c867 Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull misc kbuild changes from Michal Marek:
 "Here is the non-critical part of kbuild:
   - One bogus coccinelle check removed, one check fixed not to suggest
     the obsolete PTR_RET macro
   - scripts/tags.sh does not index the generated *.mod.c files
   - new objdiff tool to list differences between two versions of an
     object file
   - A fix for scripts/bootgraph.pl"

* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  scripts/coccinelle: Use PTR_ERR_OR_ZERO
  scripts/bootgraph.pl: Add graphic header
  scripts: objdiff: detect object code changes between two commits
  Coccicheck: Remove memcpy to struct assignment test
  scripts/tags.sh: Ignore *.mod.c
2014-04-12 18:22:27 -07:00
Behan Webster
61163efae0 kbuild: LLVMLinux: Add Kbuild support for building kernel with Clang
Add support to toplevel Makefile for compiling with clang, both for
HOSTCC and CC. Use cc-option to prevent gcc option from breaking clang, and
from clang options from breaking gcc.

Clang 3.4 semantics are the same as gcc semantics for unsupported flags. For
unsupported warnings clang 3.4 returns true but shows a warning and gcc shows
a warning and returns false.

Signed-off-by: Behan Webster <behanw@converseincode.com>
Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
Signed-off-by: Mark Charlebois <charlebm@gmail.com>
Cc: PaX Team <pageexec@freemail.hu>
2014-04-09 13:44:34 -07:00
Jason Cooper
79192ca8eb scripts: objdiff: detect object code changes between two commits
objdiff is useful when doing large code cleanups.  For example, when
removing checkpatch warnings and errors from new drivers in the staging
tree.

objdiff can be used in conjunction with a git rebase to confirm that
each commit made no changes to the resulting object code.  It has the
same return values as diff(1).

This was written specifically to support adding the skein and threefish
cryto drivers to the staging tree.  I needed a programmatic way to
confirm that commits changing >90% of the lines didn't inadvertently
change the code.

Temporary files (objdump output) are stored in

  /path/to/linux/.tmp_objdiff

'make mrproper' will remove this directory.

Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-04-08 16:41:44 +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
Linus Torvalds
b9f2b21a32 Devicetree changes for v3.15
Updates to devicetree core code. This branch contains the following notable changes:
 * Add reserved memory binding
 * Make struct device_node a kobject and remove legacy /proc/device-tree
 * ePAPR conformance fixes
 * Update in-kernel DTC copy to version v1.4.0
 * Preparation changes for dynamic device tree overlays
 * minor bug fixes and documentation changes
 
 The most significant change in this branch is the conversion of struct
 device_node to be a kobject that is exposed via sysfs and removal of the
 old /proc/device-tree code. This simplifies the device tree handling
 code and tightens up the lifecycle on device tree nodes.
 
 [updated: added fix for dangling select PROC_DEVICETREE]
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Merge tag 'dt-for-linus' of git://git.secretlab.ca/git/linux

Pull devicetree changes from Grant Likely:
 "Updates to devicetree core code.  This branch contains the following
  notable changes:

   - add reserved memory binding
   - make struct device_node a kobject and remove legacy
     /proc/device-tree
   - ePAPR conformance fixes
   - update in-kernel DTC copy to version v1.4.0
   - preparatory changes for dynamic device tree overlays
   - minor bug fixes and documentation changes

  The most significant change in this branch is the conversion of struct
  device_node to be a kobject that is exposed via sysfs and removal of
  the old /proc/device-tree code.  This simplifies the device tree
  handling code and tightens up the lifecycle on device tree nodes.

  [updated: added fix for dangling select PROC_DEVICETREE]"

* tag 'dt-for-linus' of git://git.secretlab.ca/git/linux: (29 commits)
  dt: Remove dangling "select PROC_DEVICETREE"
  of: Add support for ePAPR "stdout-path" property
  of: device_node kobject lifecycle fixes
  of: only scan for reserved mem when fdt present
  powerpc: add support for reserved memory defined by device tree
  arm64: add support for reserved memory defined by device tree
  of: add missing major vendors
  of: add vendor prefix for SMSC
  of: remove /proc/device-tree
  of/selftest: Add self tests for manipulation of properties
  of: Make device nodes kobjects so they show up in sysfs
  arm: add support for reserved memory defined by device tree
  drivers: of: add support for custom reserved memory drivers
  drivers: of: add initialization code for dynamic reserved memory
  drivers: of: add initialization code for static reserved memory
  of: document bindings for reserved-memory nodes
  Revert "of: fix of_update_property()"
  kbuild: dtbs_install: new make target
  ARM: mvebu: Allows to get the SoC ID even without PCI enabled
  of: Allows to use the PCI translator without the PCI core
  ...
2014-04-02 14:27:15 -07:00
Masahiro Yamada
1c9e70a55b kbuild: create a build directory automatically for out-of-tree build
Kbuild supports saving output files in a separate directory.
But the build directory must be created beforehand. For example,

  $ mkdir -p dir/to/store/output/files
  $ make O=dir/to/store/output/files defconfig

Creating a build directory automatically would be useful.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-03-31 22:47:16 +02:00
Masahiro Yamada
a03fcb50e8 kbuild: remove redundant '.*.cmd' pattern from make distclean
'.*.cmd' files are cleaned-up by "make clean".
The same pattern in "make distclean" is unnecessary.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-03-31 22:36:11 +02:00
Grant Likely
d88cf7d7b4 Merge remote-tracking branch 'robh/for-next' into devicetree/next 2014-03-31 08:10:55 +01:00
Linus Torvalds
455c6fdbd2 Linux 3.14 2014-03-30 20:40:15 -07:00
Paul Gortmaker
9c8cdb7164 kbuild: unconditionally clobber include/linux/version.h on distclean
As of v3.7, the UAPI changes relocated headers around such that the
kernel version header lived in a new place.

If a person is bisecting and if you go back to pre-UAPI days,
you will create an include/linux/version.h  -- then if you checkout a
post-UAPI kernel, and even run "make distclean" it still won't delete
that old version file.  So you get a situation like this:

$ grep -R LINUX_VERSION_CODE include/
include/generated/uapi/linux/version.h:#define LINUX_VERSION_CODE 200192
include/linux/version.h:#define LINUX_VERSION_CODE 132646

The value in that second line is representative of a v2.6.38 version.
And it will be sourced/used, hence leading to strange behaviours, such
as drivers/staging content (which typically hasn't been purged of version
ifdefs) failing to build.

Since it is a subtle mode of failure, lets always clobber the old
file when doing a distclean.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-03-29 20:58:18 +01:00
Linus Torvalds
b098d6726b Linux 3.14-rc8 2014-03-24 19:31:17 -07:00
Linus Torvalds
dcb99fd9b0 Linux 3.14-rc7 2014-03-16 18:51:24 -07:00