4883 Commits

Author SHA1 Message Date
723679339d kconfig: warn no new line at end of file
It would be nice to warn if a new line is missing at end of file.

We could do this by checkpatch.pl for arbitrary files, but new line
is rather essential as a statement terminator in Kconfig.

The warning message looks like this:

  kernel/Kconfig.preempt:60:warning: no new line at end of file

Currently, kernel/Kconfig.preempt is the only file with no new line
at end of file. Fix it.

I know there are some false negative cases. For example, no warning
is displayed when the last line contains some whitespaces/comments,
but no new line. Yet, this commit works well for most cases.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-15 17:44:35 +09:00
3a6ab5c7dc scripts/spdxcheck.py: always open files in binary mode
The spdxcheck script currently falls over when confronted with a binary
file (such as Documentation/logo.gif).  To avoid that, always open files
in binary mode and decode line-by-line, ignoring encoding errors.

One tricky case is when piping data into the script and reading it from
standard input.  By default, standard input will be opened in text mode,
so we need to reopen it in binary mode.

The breakage only happens with python3 and results in a
UnicodeDecodeError (according to Uwe).

Link: http://lkml.kernel.org/r/20181212131210.28024-1-thierry.reding@gmail.com
Fixes: 6f4d29df66ac ("scripts/spdxcheck.py: make python3 compliant")
Signed-off-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Jeremy Cline <jcline@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Joe Perches <joe@perches.com>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-14 15:05:45 -08:00
f1733a1d3c checkstack.pl: fix for aarch64
There is actually a space after "sp," like this,

    ffff2000080813c8:       a9bb7bfd        stp     x29, x30, [sp, #-80]!

Right now, checkstack.pl isn't able to print anything on aarch64,
because it won't be able to match the stating objdump line of a function
due to this missing space.  Hence, it displays every stack as zero-size.

After this patch, checkpatch.pl is able to match the start of a
function's objdump, and is then able to calculate each function's stack
correctly.

Link: http://lkml.kernel.org/r/20181207195843.38528-1-cai@lca.pw
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-14 15:05:45 -08:00
acc2038738 Merge branch 'yaml-bindings-for-v4.21' into dt/next 2018-12-13 11:20:36 -06:00
4f0e3a57d6 kbuild: Add support for DT binding schema checks
This adds the build infrastructure for checking DT binding schema
documents and validating dts files using the binding schema.

Check DT binding schema documents:
make dt_binding_check

Build dts files and check using DT binding schema:
make dtbs_check

Optionally, DT_SCHEMA_FILES can be passed in with a schema file(s) to
use for validation. This makes it easier to find and fix errors
generated by a specific schema.

Currently, the validation targets are separate from a normal build to
avoid a hard dependency on the external DT schema project and because
there are lots of warnings generated.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: linux-doc@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-kbuild@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
2018-12-13 09:41:32 -06:00
189af46571 ARM: smp: add support for per-task stack canaries
On ARM, we currently only change the value of the stack canary when
switching tasks if the kernel was built for UP. On SMP kernels, this
is impossible since the stack canary value is obtained via a global
symbol reference, which means
a) all running tasks on all CPUs must use the same value
b) we can only modify the value when no kernel stack frames are live
   on any CPU, which is effectively never.

So instead, use a GCC plugin to add a RTL pass that replaces each
reference to the address of the __stack_chk_guard symbol with an
expression that produces the address of the 'stack_canary' field
that is added to struct thread_info. This way, each task will use
its own randomized value.

Cc: Russell King <linux@armlinux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Laura Abbott <labbott@redhat.com>
Cc: kernel-hardening@lists.openwall.com
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2018-12-12 13:20:07 -08:00
0bcc547ec4 kconfig: clean up EOF handling in the lexer
A new file should always start in the INITIAL state.

When the lexer bumps into EOF, the lexer must get back to the INITIAL
state anyway. Remove the redundant <<EOF>> pattern in the PARAM state.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-13 00:20:09 +09:00
cc66bca775 kconfig: fix ambiguous grammar in terms of new lines
This commit decreases 8 shift/reduce conflicts.

A certain amount of grammatical ambiguity comes from how to reduce
excessive T_EOL tokens.

Let's take a look at the example code below:

  1  config A
  2          bool "a"
  3
  4          depends on B
  5
  6  config B
  7          def_bool y

The line 3 is melt into "config_option_list", but the line 5 can be
either a part of "config_option_list" or "common_stmt" by itself.

Currently, the lexer converts '\n' to T_EOL verbatim. In Kconfig,
a new line works as a statement terminator, but new lines in empty
lines are not critical since empty lines (or lines that contain only
whitespaces/comments) are just no-op.

If the lexer simply discards no-op lines, the parser will not be
bothered by excessive T_EOL tokens.

Of course, this means we are shifting the complexity from the parser
to the lexer, but it is much easier than tackling on shift/reduce
conflicts.

I introduced the second stage lexer to tweak the behavior.

Discard T_EOL if the previous token is T_EOL or T_HELPTEXT.
Two T_EOL tokens in a row is meaningless. T_HELPTEXT is a special
token that is reduced without T_EOL.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-13 00:18:54 +09:00
21c5ecf604 kconfig: refactor pattern matching in STRING state
Here, similar matching patters are duplicated in order to look ahead
the '\n' character. If the next character is '\n', the lexer returns
T_WORD_QUOTE because it must be prepared to return T_EOL at the next
match.

Use unput('\n') trick to reduce the code duplication.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-13 00:16:24 +09:00
be3c807597 kconfig: remove unneeded pattern matching to whitespaces
Whitespaces are consumed in the COMMAND state anyway.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-13 00:16:23 +09:00
413cd19d81 kconfig: require T_EOL to reduce visible statement
All line-oriented statements should be reduced when seeing a T_EOL
token. I guess missing T_EOL for the "visible" statement is just a
mistake. This commit decreases one shift/reduce conflict.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-13 00:16:22 +09:00
fbac5977d8 kconfig: fix memory leak when EOF is encountered in quotation
An unterminated string literal followed by new line is passed to the
parser (with "multi-line strings not supported" warning shown), then
handled properly there.

On the other hand, an unterminated string literal at end of file is
never passed to the parser, then results in memory leak.

[Test Code]

  ----------(Kconfig begin)----------
  source "Kconfig.inc"

  config A
          bool "a"
  -----------(Kconfig end)-----------

  --------(Kconfig.inc begin)--------
  config B
          bool "b\No new line at end of file
  ---------(Kconfig.inc end)---------

[Summary from Valgrind]

  Before the fix:

    LEAK SUMMARY:
       definitely lost: 16 bytes in 1 blocks
       ...

  After the fix:

    LEAK SUMMARY:
       definitely lost: 0 bytes in 0 blocks
       ...

Eliminate the memory leak path by handling this case. Of course, such
a Kconfig file is wrong already, so I will add an error message later.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-13 00:16:21 +09:00
77c1c0fa8b kconfig: fix file name and line number of warn_ignored_character()
Currently, warn_ignore_character() displays invalid file name and
line number.

The lexer should use current_file->name and yylineno, while the parser
should use zconf_curname() and zconf_lineno().

This difference comes from that the lexer is always going ahead
of the parser. The parser needs to look ahead one token to make a
shift/reduce decision, so the lexer is requested to scan more text
from the input file.

This commit fixes the warning message from warn_ignored_character().

[Test Code]

  ----(Kconfig begin)----
  /
  -----(Kconfig end)-----

[Output]

  Before the fix:

  <none>:0:warning: ignoring unsupported character '/'

  After the fix:

  Kconfig:1:warning: ignoring unsupported character '/'

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-13 00:16:20 +09:00
930e12992e parisc: syscalls: ignore nfsservctl for other architectures
This adds an exception to the syscall table checking script.

nfsservctl entry is only provided on x86, and there is no
reason to add it elsewhere. However, including it on the
syscall table caused a warning for most configurations on
non-x86.

<stdin>:696:2: warning: #warning syscall nfsservctl not implemented [-Wcpp]

Signed-off-by: Firoz Khan <firoz.khan@linaro.org>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>
2018-12-10 08:26:04 +01:00
9c8e2f6d3d scripts/recordmcount.{c,pl}: support -ffunction-sections .text.* section names
When building with -ffunction-sections, the compiler will place each
function into its own ELF section, prefixed with ".text".  For example,
a simple test module with functions test_module_do_work() and
test_module_wq_func():

  % objdump --section-headers test_module.o | awk '/\.text/{print $2}'
  .text
  .text.test_module_do_work
  .text.test_module_wq_func
  .init.text
  .exit.text

Adjust the recordmcount scripts to look for ".text" as a section name
prefix.  This will ensure that those functions will be included in the
__mcount_loc relocations:

  % objdump --reloc --section __mcount_loc test_module.o
  OFFSET           TYPE              VALUE
  0000000000000000 R_X86_64_64       .text.test_module_do_work
  0000000000000008 R_X86_64_64       .text.test_module_wq_func
  0000000000000010 R_X86_64_64       .init.text

Link: http://lkml.kernel.org/r/1542745158-25392-2-git-send-email-joe.lawrence@redhat.com

Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:08 -05:00
5e34bd1d54 kbuild: remove a special handling for *.agh in Makefile.headersinst
scripts/Makefile.headersinst takes care of *.agh just for

  arch/cris/include/uapi/arch-v10/arch/sv_addr.agh

because renaming exported headers is difficult (or impossible).

This code is no longer necessary thanks to commit c690eddc2f3b ("CRIS:
Drop support for the CRIS port").

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-08 10:52:20 +09:00
0cbe3ac439 kconfig: remove k_invalid from expr_parse_string() return type
The only possibility of k_invalid being returned was when
expr_parse_sting() parsed S_OTHER type symbol. This actually never
happened, and this is even clearer since S_OTHER has gone.

Clean up unreachable code.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-08 10:42:42 +09:00
2aabbed677 kconfig: remove S_OTHER symbol type and correct dependency tracking
The S_OTHER type could be set only when conf_read_simple() is reading
include/config/auto.conf file.

For example, CONFIG_FOO=y exists in include/config/auto.conf but it is
missing from the currently parsed Kconfig files, sym_lookup() allocates
a new symbol, and sets its type to S_OTHER.

Strangely, it will be set to S_STRING by conf_set_sym_val() a few lines
below while it is obviously bool or tristate type. On the other hand,
when CONFIG_BAR="bar" is being dropped from include/config/auto.conf,
its type remains S_OTHER. Because for_all_symbols() omits S_OTHER
symbols, conf_touch_deps() misses to touch include/config/bar.h

This behavior has been a pretty mystery for me, and digging the git
histroy did not help. At least, touching depfiles is broken for string
type symbols.

I removed S_OTHER entirely, and reimplemented it more simply.

If CONFIG_FOO was visible in the previous syncconfig, but is missing
now, what we want to do is quite simple; just call conf_touch_dep()
to touch include/config/foo.h instead of allocating a new symbol data.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-08 10:42:41 +09:00
1508fec82e kconfig: split out code touching a file to conf_touch_dep()
conf_touch_deps() iterates over symbols, touching corresponding
include/config/*.h files as needed.

Split the part that touches a single file into a new helper so it can
be reused.

The new helper, conf_touch_dep(), takes a symbol name as a parameter,
and touches the corresponding include/config/*.h file.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-08 10:42:30 +09:00
0849d212e3 kconfig: rename conf_split_config() to conf_touch_deps()
According to commit 2e3646e51b2d ("kconfig: integrate split config
into silentoldconfig"), this function was named after split-include
tool, which used to exist in old versions of Linux.

Setting aside the historical reason, rename it into a more intuitive
name. This function touches timestamp files under include/config/
in order to interact with the fixdep tool.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-08 10:40:52 +09:00
75889e9be7 kconfig: remove unneeded setsym label in conf_read_simple()
The two 'goto setsym' statements are reachable only when sym == NULL.

The code below the 'setsym:' label does nothing when sym == NULL
since there is just one if-block guarded by 'if (sym && ...)'.

Hence, 'goto setsym' can be replaced with 'continue'.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-08 10:40:52 +09:00
1cdc3624a1 Fixes for stackleak
- Remove tracing for inserted stack depth marking function (Anders Roxell)
 - Move gcc-plugin pass location to avoid objtool warnings (Alexander Popov)
 -----BEGIN PGP SIGNATURE-----
 Comment: Kees Cook <kees@outflux.net>
 
 iQJKBAABCgA0FiEEpcP2jyKd1g9yPm4TiXL039xtwCYFAlwKp1IWHGtlZXNjb29r
 QGNocm9taXVtLm9yZwAKCRCJcvTf3G3AJuT9D/9DP75YerfMFxiVx8BsFnGVfPW3
 QWa/nf2c8VMhmouQ9OI8j8Nj+T4q5VXewbGC5I0F6b2YsIPjHOwK0PR557xn7jRi
 7bY3aTRzJs4v+dDYkXqTkGx4zQ9FSD3NDM0T4vtnVGEdOmojcvoLX6+V7WArOTaa
 M9oP4iNn5/+Z677HyMP3DyTY093WpCx0fNOAf1HI/kpM3TPVJiE5OLXBZY957N01
 eBrt0WHJkmaZkHeqUkK06RTxYzIKBQqFRw77pPiKq79ETxBEwHOgU2hmwwHBv4+h
 u6TQmy7aVsUiXfS1GVvkNkX/jCNxYuK8kP5dsd+cQKn3AfkDHj3RvBTOvrkD0xyF
 7F9Toz/Wpw8+/YVx8ks6cNrssmEq4rd6T7MJcoud1TwEG1o/bSUbPc4uednuIUGL
 sB4J6sxApL2vaZtgqUePVZZJVKwiryFa8LymihkHMfPU4dgCycrYLGa3A1ju9WVs
 psGYhFTEfC1KVLgTmfwZlxz/FWbRmSERRF7cl9cdw8mdlqkKxP1C//VgsdJXOnnW
 c51BS+XK9OI8HTYXmWah82ysuCE7qou4DUJA91jhyza5tEp2V5C0uhOQz2odFcBF
 8axjqExFr4YfAwIgtGOClPA0e5CaB4ASRbOIs8+WL03LiNbfP/p6+92TpnwaP637
 Q5CbAMIfKqNpqAcAJg==
 =1JZ6
 -----END PGP SIGNATURE-----

Merge tag 'gcc-plugins-v4.20-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull gcc stackleak plugin fixes from Kees Cook:

 - Remove tracing for inserted stack depth marking function (Anders
   Roxell)

 - Move gcc-plugin pass location to avoid objtool warnings (Alexander
   Popov)

* tag 'gcc-plugins-v4.20-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  stackleak: Register the 'stackleak_cleanup' pass before the '*free_cfg' pass
  stackleak: Mark stackleak_track_stack() as notrace
2018-12-07 13:13:07 -08:00
8fb2dfb228 stackleak: Register the 'stackleak_cleanup' pass before the '*free_cfg' pass
Currently the 'stackleak_cleanup' pass deleting a CALL insn is executed
after the 'reload' pass. That allows gcc to do some weird optimization in
function prologues and epilogues, which are generated later [1].

Let's avoid that by registering the 'stackleak_cleanup' pass before
the '*free_cfg' pass. It's the moment when the stack frame size is
already final, function prologues and epilogues are generated, and the
machine-dependent code transformations are not done.

[1] https://www.openwall.com/lists/kernel-hardening/2018/11/23/2

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Alexander Popov <alex.popov@linux.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2018-12-06 09:10:23 -08:00
4bbfd7467c Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU changes from Paul E. McKenney:

- Convert RCU's BUG_ON() and similar calls to WARN_ON() and similar.

- Replace calls of RCU-bh and RCU-sched update-side functions
  to their vanilla RCU counterparts.  This series is a step
  towards complete removal of the RCU-bh and RCU-sched update-side
  functions.

  ( Note that some of these conversions are going upstream via their
    respective maintainers. )

- Documentation updates, including a number of flavor-consolidation
  updates from Joel Fernandes.

- Miscellaneous fixes.

- Automate generation of the initrd filesystem used for
  rcutorture testing.

- Convert spin_is_locked() assertions to instead use lockdep.

  ( Note that some of these conversions are going upstream via their
    respective maintainers. )

- SRCU updates, especially including a fix from Dennis Krein
  for a bag-on-head-class bug.

- RCU torture-test updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-12-04 07:52:30 +01:00
8e9b61b293 kbuild: move .SECONDARY special target to Kbuild.include
In commit 54a702f70589 ("kbuild: mark $(targets) as .SECONDARY and
remove .PRECIOUS markers"), I missed one important feature of the
.SECONDARY target:

    .SECONDARY with no prerequisites causes all targets to be
    treated as secondary.

... which agrees with the policy of Kbuild.

Let's move it to scripts/Kbuild.include, with no prerequisites.

Note:
If an intermediate file is generated by $(call if_changed,...), you
still need to add it to "targets" so its .*.cmd file is included.

The arm/arm64 crypto files are generated by $(call cmd,shipped),
so they do not need to be added to "targets", but need to be added
to "clean-files" so "make clean" can properly clean them away.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-02 14:11:49 +09:00
4b78317679 Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull STIBP fallout fixes from Thomas Gleixner:
 "The performance destruction department finally got it's act together
  and came up with a cure for the STIPB regression:

   - Provide a command line option to control the spectre v2 user space
     mitigations. Default is either seccomp or prctl (if seccomp is
     disabled in Kconfig). prctl allows mitigation opt-in, seccomp
     enables the migitation for sandboxed processes.

   - Rework the code to handle the conditional STIBP/IBPB control and
     remove the now unused ptrace_may_access_sched() optimization
     attempt

   - Disable STIBP automatically when SMT is disabled

   - Optimize the switch_to() logic to avoid MSR writes and invocations
     of __switch_to_xtra().

   - Make the asynchronous speculation TIF updates synchronous to
     prevent stale mitigation state.

  As a general cleanup this also makes retpoline directly depend on
  compiler support and removes the 'minimal retpoline' option which just
  pretended to provide some form of security while providing none"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits)
  x86/speculation: Provide IBPB always command line options
  x86/speculation: Add seccomp Spectre v2 user space protection mode
  x86/speculation: Enable prctl mode for spectre_v2_user
  x86/speculation: Add prctl() control for indirect branch speculation
  x86/speculation: Prepare arch_smt_update() for PRCTL mode
  x86/speculation: Prevent stale SPEC_CTRL msr content
  x86/speculation: Split out TIF update
  ptrace: Remove unused ptrace_may_access_sched() and MODE_IBRS
  x86/speculation: Prepare for conditional IBPB in switch_mm()
  x86/speculation: Avoid __switch_to_xtra() calls
  x86/process: Consolidate and simplify switch_to_xtra() code
  x86/speculation: Prepare for per task indirect branch speculation control
  x86/speculation: Add command line control for indirect branch speculation
  x86/speculation: Unify conditional spectre v2 print functions
  x86/speculataion: Mark command line parser data __initdata
  x86/speculation: Mark string arrays const correctly
  x86/speculation: Reorder the spec_v2 code
  x86/l1tf: Show actual SMT state
  x86/speculation: Rework SMT state change
  sched/smt: Expose sched_smt_present static key
  ...
2018-12-01 12:35:48 -08:00
5439f09f48 kbuild: remove redundant 'set -e' from cmd_* defines
These three cmd_* are invoked in the $(call cmd,*) form.

Now that 'set -e' moved to the 'cmd' macro, they do not need to
explicitly give 'set -e'.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-01 23:13:14 +09:00
67126965ee kbuild: refactor if_changed
'@set -e; $(echo-cmd) $(cmd_$(1)' can be replaced with '$(cmd)'.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-01 23:13:14 +09:00
e5d289100d kbuild: remove trailing semicolon from cmd_* passed to if_changed_rule
With the change of rule_cc_o_c / rule_as_o_S in the last commit, each
command is executed in a separate subshell. Rip off unneeded semicolons.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-01 23:13:14 +09:00
3a2429e1fa kbuild: change if_changed_rule for multi-line recipe
The 'define' ... 'endef' directive is useful to confine a series of
shell commands into a single macro:

  define foo
          [action1]
          [action2]
          [action3]
  endif

Each action is executed in a separate subshell.

However, rule_cc_o_c and rule_as_o_S in scripts/Makefile.build are
written as follows (with a trailing semicolon in each cmd_*):

  define rule_cc_o_c
          [action1] ; \
          [action2] ; \
          [action3] ;
  endef

All shell commands are concatenated with '; \' so that it looks like
a single command from the Makefile point of view. This does not
exploit the benefits of 'define' ... 'endef' form because a single
shell command can be more simply written, like this:

  rule_cc_o_c = \
          [action1] ; \
          [action2] ; \
          [action3] ;

I guess the intention for the command concatenation was to let the
'@set -e' in if_changed_rule cover all the commands.

We can improve the readability by moving '@set -e' to the 'cmd' macro.
The combo of $(call echo-cmd,*) $(cmd_*) in rule_cc_o_c and rule_as_o_S
have been replaced with $(call cmd,*). The trailing back-slashes have
been removed.

Here is a note about the performance: the commands in rule_cc_o_c and
rule_as_o_S were previously executed all together in a single subshell,
but now each line in a separate subshell. This means Make will spawn
extra subshells [1]. I measured the build performance for
  x86_64_defconfig + CONFIG_MODVERSIONS + CONFIG_TRIM_UNUSED_KSYMS
and I saw slight performance regression, but I believe code readability
and maintainability wins.

[1] Precisely, GNU Make may optimize this by executing the command
    directly instead of forking a subshell, if no shell special
    characters are found in the command line and omitting the subshell
    will not change the behavior.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-01 23:13:14 +09:00
bbda5ec671 kbuild: simplify dependency generation for CONFIG_TRIM_UNUSED_KSYMS
My main motivation of this commit is to clean up scripts/Kbuild.include
and scripts/Makefile.build.

Currently, CONFIG_TRIM_UNUSED_KSYMS works with a tricky gimmick;
possibly exported symbols are detected by letting $(CPP) replace
EXPORT_SYMBOL* with a special string '=== __KSYM_*===', which is
post-processed by sed, and passed to fixdep. The extra preprocessing
is costly, and hacking cmd_and_fixdep is ugly.

I came up with a new way to find exported symbols; insert a dummy
symbol __ksym_marker_* to each potentially exported symbol. Those
dummy symbols are picked up by $(NM), post-processed by sed, then
appended to .*.cmd files. I collected the post-process part to a
new shell script scripts/gen_ksymdeps.sh for readability. The dummy
symbols are put into the .discard.* section so that the linker
script rips them off the final vmlinux or modules.

A nice side-effect is building with CONFIG_TRIM_UNUSED_KSYMS will
be much faster.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
2018-12-01 23:13:14 +09:00
ee3e46b7ef kbuild: refactor modversions build rules
Let $(CC) compile objects into normal files *.o instead of .tmp_*.o
whether CONFIG_MODVERSIONS is enabled or not. With this, the input
file for objtool is always *.o so objtool_o can go away.

I guess the reason of using .tmp_*.o for intermediate objects was
to avoid leaving incomplete *.o file (, whose timestamp says it is
up-to-date) when the genksyms tool failed for some reasons.

It no longer matters because any targets are deleted on errors since
commit 9c2af1c7377a ("kbuild: add .DELETE_ON_ERROR special target").

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-01 23:13:14 +09:00
4317ee3b6a kbuild: remove redundant 'set -e' from sub_cmd_record_mcount
This is executed inside the if_changed_rule, which already sets
'set -e'.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-01 23:13:14 +09:00
f3fd4a3f3a kbuild: remove redundant 'set -e' from filechk_offsets
The filechk macro in scripts/Kbuild.include already sets 'set -e'.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-01 23:13:14 +09:00
392885ee82 kbuild: let fixdep directly write to .*.cmd files
Currently, fixdep writes dependencies to .*.tmp, which is renamed to
.*.cmd after everything succeeds. This is a very safe way to avoid
corrupted .*.cmd files. The if_changed_dep has carried this safety
mechanism since it was added in 2002.

If fixdep fails for some reasons or a user terminates the build while
fixdep is running, the incomplete output from the fixdep could be
troublesome.

This is my insight about some bad scenarios:

[1] If the compiler succeeds to generate *.o file, but fixdep fails
    to write necessary dependencies to .*.cmd file, Make will miss
    to rebuild the object when headers or CONFIG options are changed.
    In this case, fixdep should not generate .*.cmd file at all so
    that 'arg-check' will surely trigger the rebuild of the object.

[2] A partially constructed .*.cmd file may not be a syntactically
    correct makefile. The next time Make runs, it would include it,
    then fail to parse it. Once this happens, 'make clean' is be the
    only way to fix it.

In fact, [1] is no longer a problem since commit 9c2af1c7377a ("kbuild:
add .DELETE_ON_ERROR special target"). Make deletes a target file on
any failure in its recipe. Because fixdep is a part of the recipe of
*.o target, if it fails, the *.o is deleted anyway. However, I am a
bit worried about the slight possibility of [2].

So, here is a solution. Let fixdep directly write to a .*.cmd file,
but allow makefiles to include it only when its corresponding target
exists.

This effectively reverts commit 2982c953570b ("kbuild: remove redundant
$(wildcard ...) for cmd_files calculation"), and commit 00d78ab2ba75
("kbuild: remove dead code in cmd_files calculation in top Makefile")
because now we must check the presence of targets.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-01 23:13:14 +09:00
ce2fd53a10 kbuild: descend into scripts/gcc-plugins/ via scripts/Makefile
Now that 'archprepare' depends on 'scripts', Kbuild can descend into
scripts/gcc-plugins in a more standard way.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2018-12-01 23:09:38 +09:00
60df1aee2a kbuild: move modpost out of 'scripts' target
I am eagar to build under the scripts/ directory only with $(HOSTCC),
but scripts/mod/ highly depends on the $(CC) and target arch headers.
That it why the 'scripts' target must depend on 'asm-generic',
'gcc-plugins', and $(autoksyms_h).

Move it to the 'prepare0' stage. I know this is a cheesy workaround,
but better than the current situation.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-01 23:09:34 +09:00
3b41528803 modpost: move unresolved symbol checks to check_exports()
This will fit better in check_exports() than add_versions().

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-01 22:21:59 +09:00
c6826ad8a4 modpost: merge module iterations
Probably, this is just a matter of the order of error/warning
messages. Merge the two for-loops.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-01 22:21:58 +09:00
d2665ca8e3 modpost: refactor seen flag clearing in add_depends()
You do not need to iterate over all modules for resetting ->seen flag
because add_depends() is only interested in modules that export symbols
referenced from the given 'mod'.

This also avoids shadowing the 'modules' parameter of add_depends().

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-01 22:21:58 +09:00
f880eea68f modpost: file2alias: check prototype of handler
Use specific prototype instead of an opaque pointer so that the
compiler can catch function prototype mismatch.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Mathieu Malaterre <malat@debian.org>
2018-12-01 22:21:58 +09:00
ec91e78d37 modpost: file2alias: go back to simple devtable lookup
Commit e49ce14150c6 ("modpost: use linker section to generate table.")
was not so cool as we had expected first; it ended up with ugly section
hacks when commit dd2a3acaecd7 ("mod/file2alias: make modpost compile
on darwin again") came in.

Given a certain degree of unknowledge about the link stage of host
programs, I really want to see simple, stupid table lookup so that
this works in the same way regardless of the underlying executable
format.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Mathieu Malaterre <malat@debian.org>
2018-12-01 22:21:57 +09:00
a4d26f1a09 modpost: skip ELF local symbols during section mismatch check
During development of a serial console driver with a gcc 8.2.0
toolchain for RISC-V, the following modpost warning appeared:

----
WARNING: vmlinux.o(.data+0x19b10): Section mismatch in reference from the variable .LANCHOR1 to the function .init.text:sifive_serial_console_setup()
The variable .LANCHOR1 references
the function __init sifive_serial_console_setup()
If the reference is valid then annotate the
variable with __init* or __refdata (see linux/init.h) or name the variable:
*_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console
----

".LANCHOR1" is an ELF local symbol, automatically created by gcc's section
anchor generation code:

https://gcc.gnu.org/onlinedocs/gccint/Anchored-Addresses.html

https://gcc.gnu.org/git/?p=gcc.git;a=blob;f=gcc/varasm.c;h=cd9591a45617464946dcf9a126dde277d9de9804;hb=9fb89fa845c1b2e0a18d85ada0b077c84508ab78#l7473

This was verified by compiling the kernel with -fno-section-anchors
and observing that the ".LANCHOR1" ELF local symbol disappeared, and
modpost no longer warned about the section mismatch.  The serial
driver code idiom triggering the warning is standard Linux serial
driver practice that has a specific whitelist inclusion in modpost.c.

I'm neither a modpost nor an ELF expert, but naively, it doesn't seem
useful for modpost to report section mismatch warnings caused by ELF
local symbols by default.  Local symbols have compiler-generated
names, and thus bypass modpost's whitelisting algorithm, which relies
on the presence of a non-autogenerated symbol name.  This increases
the likelihood that false positive warnings will be generated (as in
the above case).

Thus, disable section mismatch reporting on ELF local symbols.  The
rationale here is similar to that of commit 2e3a10a1551d ("ARM: avoid
ARM binutils leaking ELF local symbols") and of similar code already
present in modpost.c:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/scripts/mod/modpost.c?h=v4.19-rc4&id=7876320f88802b22d4e2daf7eb027dd14175a0f8#n1256

This third version of the patch implements a suggestion from Masahiro
Yamada <yamada.masahiro@socionext.com> to restructure the code as an
additional pattern matching step inside secref_whitelist(), and
further improves the patch description.

Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-01 22:21:56 +09:00
38c7b224ce unifdef: use memcpy instead of strncpy
New versions of gcc reasonably warn about the odd pattern of

	strncpy(p, q, strlen(q));

which really doesn't make sense: the strncpy() ends up being just a slow
and odd way to write memcpy() in this case.

There was a comment about _why_ the code used strncpy - to avoid the
terminating NUL byte, but memcpy does the same and avoids the warning.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-11-30 14:45:01 -08:00
a2237fec1e kbuild: Enable dtc graph_port warning by default
All the 'graph_port' warnings have been fixed or have pending fixes, so
we can enable it by default now.

Signed-off-by: Rob Herring <robh@kernel.org>
2018-11-30 09:10:29 -06:00
70523a3ce5 kbuild: disable dtc simple_bus_reg warnings by default
The updated version of dtc has a bug fix for simple_bus_reg warnings
and lots of warnings are generated now. So disable this warning by
default.

Signed-off-by: Rob Herring <robh@kernel.org>
2018-11-30 09:03:54 -06:00
c2e7075ca8 scripts/dtc: Update to upstream version v1.4.7-57-gf267e674d145
This adds the following commits from upstream:

f267e674d145 checks: Fix crash with multiple source annotations
3616b9a811b6 checks: Use source position information for check failures
2bdbd07a1223 checks: Make each message output atomic
a1eff70c02cf util: Add xa{v}sprintf_append functions
82a52ce4573b libfdt: Add a test for fdt_getprop_by_offset()
607b8586b383 PEP8 / Flake8 cleanups for setup.py
f9c0a425b648 Remove broken objdir / srcdir support
5182b5e6f28c pylibfdt: Use common PREFIX variable
d45bf1f5f2a6 Refine make tests_clean target
99284c4db9cb Refine pylibfdt_clean target
a4629cfaedfb Refine libfdt_clean target
08380fc43aa2 tests: Use modern octal literals for Python
8113c00b99d3 pylibfdt: Allow switch to Python 3 via environment variable PYTHON
11738cf01f15 libfdt: Don't use memcpy to handle unaligned reads on ARM
86a288a73670 checks: Restructure check_msg to decrease indentation
5667e7ef9a9a annotations: add the annotation functionality
8e20ccf52f90 annotations: add positions
ca930e20bb54 tests: Don't lose errors from make checkm
43366bb4eeee tests: Property count valgrind errors in wrapped tests
5062516fb8cb srcpos: Remove srcpos_empty
a3143fafbf83 Revert "annotations: add positions"
403cc79f06a1 checks: Update SPI bus check for 'spi-slave'
baa1d2cf7894 annotations: add positions
ff2ad38f6a5a Merge remote-tracking branch 'origin/pr/18'
aa7254d9cb17 libfdt: return correct value if #size-cells property is not present
49903aed7783 use ptrdiff_t modifier for printing pointer differences
da2b691ccf68 treesource: Fix dts output for phandles in middle of a sequence of ints
8f8b77a0d62d tests: Wrap check_align() calls with base_run_test()
522d81d572f2 Fix dts output with a REF_PATH marker
e45198c98359 Added test cases for target references
0fcffda15e9f Merge nodes with local target label references
1e4a0928f3b3 pylibfdt: Don't have setup.py depend on where it's invoked from
ca399b14956f pylibfdt: Eliminate run_setup make function
98972f1b3e33 pylibfdt: Improved version extraction
7ba2be6cda5f pylibfdt: Don't silence setup.py when V=1
7691f9d39301 pylibfdt: Make SETUP make variable
855b9963def9 pylibfdt: Simpler CFLAGS handling
47cafbeeb977 pylibfdt: Link extension module with libfdt rather than rebuilding
dd695d6afb19 pylibfdt: Correctly set build output directory
59327523d0d8 pylibfdt: We don't need include files from the base directory
e84742aa7b93 checks: fix simple-bus compatible matching
8c59a97ce096 Fix missing labels when emitting dts format
d448f9a5fd94 Revert dts output formatting changes of spaces around brackets

Signed-off-by: Rob Herring <robh@kernel.org>
2018-11-28 18:37:35 -06:00
61647c77cb drm-misc-next for v4.21:
Core Changes:
 - Merge drm_info.c into drm_debugfs.c
 - Complete the fake drm_crtc_commit's hw_done/flip_done sooner.
 - Remove deprecated drm_obj_ref/unref functions. All drivers use get/put now.
 - Decrease stack use of drm_gem_prime_mmap.
 - Improve documentation for dumb callbacks.
 
 Driver Changes:
 - Add edid support to virtio.
 - Wait on implicit fence in meson and sun4i.
 - Add support for BGRX8888 to sun4i.
 - Preparation patches for sun4i driver to start supporting linear and tiled YUV formats.
 - Add support for HDMI 1.4 4k modes to meson, and support for VIC alternate timings.
 - Drop custom dumb_map in vkms.
 - Small fixes and cleanups to v3d.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEuXvWqAysSYEJGuVH/lWMcqZwE8MFAlv+YOEACgkQ/lWMcqZw
 E8OJvw//fc+j9sJLScvrahLDNZVMh4pTvQCOySmxIPVAhjLZIkRjdvR9Ou51tbL+
 qSm3tDexHEPniR8xmuTYjPZtJP6o4e4NLqUzWYdZb0U+oK3QMuJKDD3uK+6BwM8P
 CyAa4VxV9F17oN+d0aFpoPTHheRVt3egyvREqLHoiAJYtp01cm+f/FFKZSe+o3p/
 QLi0tJ5unXg6AZFoomYbZirE/jp6t8m+cjRkYOafE57+2qpMEJ8RA5G0D1UxCgP2
 imGW6n4N7rmB1bNbtTvFEDGIffE+W9AkVQkJ2YXUfQldtmUKgLA9OG47DIdDb1Xa
 P7RWVjHJejhvu9URcFmQcrjoCtKURPcPTuLZEQHvae1sUxwwMUvtpKUM7TBGYo2I
 G/nQLkMLmK9yfJRyo2OHRHTClduU3X7FXzbJhbL3cUMx0beWjCQmRDjM9ywfSJR3
 lrJIlnQ3voCp0IZWj86RG0idpd3RIjE8Aaqz/m4bSmqMCqmlepnZzIpZcFB7gXbM
 k0xiK4LUFO1VbFsMoRaqrP1zXduY+nbLhfiDiIDs34v0ZVqNooJpLYilRI/lvmXt
 vzApnxgwRePW0vz67Lagqq+ZUXJXptirmGw7bnvfT90cOKlRLi5CDZTRwCOuUNPL
 9kUgXj8EoX9+7p9M14TrEx9tV0MZIwbP8nlS9Ty0Kx4s240mbYg=
 =JNy2
 -----END PGP SIGNATURE-----

Merge tag 'drm-misc-next-2018-11-28' of git://anongit.freedesktop.org/drm/drm-misc into drm-next

drm-misc-next for v4.21:

Core Changes:
- Merge drm_info.c into drm_debugfs.c
- Complete the fake drm_crtc_commit's hw_done/flip_done sooner.
- Remove deprecated drm_obj_ref/unref functions. All drivers use get/put now.
- Decrease stack use of drm_gem_prime_mmap.
- Improve documentation for dumb callbacks.

Driver Changes:
- Add edid support to virtio.
- Wait on implicit fence in meson and sun4i.
- Add support for BGRX8888 to sun4i.
- Preparation patches for sun4i driver to start supporting linear and tiled YUV formats.
- Add support for HDMI 1.4 4k modes to meson, and support for VIC alternate timings.
- Drop custom dumb_map in vkms.
- Small fixes and cleanups to v3d.

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/151a3270-b1be-ed75-bd58-6b29d741f592@linux.intel.com
2018-11-29 10:28:49 +10:00
4cd24de3a0 x86/retpoline: Make CONFIG_RETPOLINE depend on compiler support
Since retpoline capable compilers are widely available, make
CONFIG_RETPOLINE hard depend on the compiler capability.

Break the build when CONFIG_RETPOLINE is enabled and the compiler does not
support it. Emit an error message in that case:

 "arch/x86/Makefile:226: *** You are building kernel with non-retpoline
  compiler, please update your compiler..  Stop."

[dwmw: Fail the build with non-retpoline compiler]

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Borislav Petkov <bp@suse.de>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: <srinivas.eeda@oracle.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/cca0cb20-f9e2-4094-840b-fb0f8810cd34@default
2018-11-28 11:57:03 +01:00
3d9bfb19bd scripts/kernel-doc: Fix struct and struct field attribute processing
The kernel-doc attempts to clear the struct and struct member attributes
from the API documentation it produces. It falls short of the job in the
following respects:

- extra whitespaces are left where __attribute__((...)) was removed,

- only a single attribute is removed per struct,

- attributes (such as aligned) containing numbers were not removed,

- attributes are only cleared from struct fields, not structs themselves.

This patch addresses these issues by removing the attributes.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-25 12:35:45 -07:00