Commit Graph

738 Commits

Author SHA1 Message Date
Masahiro Yamada
4bb3a5b085 kconfig: remove unneeded input_mode test in conf()
conf() is never called for listnewconfig / olddefconfig.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-26 02:03:59 +09:00
Masahiro Yamada
59a80b5e89 kconfig: do not call check_conf() for olddefconfig
check_conf() traverses the menu tree, but it is completely no-op for
olddefconfig because the following if-else block does nothing.

    if (input_mode == listnewconfig) {
            ...
    } else if (input_mode != olddefconfig) {
            ...
    }

As the help message says, olddefconfig automatically sets new symbols
to their default value.  There is no room for manual intervention.
So, calling check_conf() for olddefconfig is odd in the first place.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-26 02:03:58 +09:00
Ulf Magnusson
f467c5640c kconfig: only write '# CONFIG_FOO is not set' for visible symbols
=== Background ===

 - Visible n-valued bool/tristate symbols generate a
   '# CONFIG_FOO is not set' line in the .config file. The idea is to
   remember the user selection without having to set a Makefile
   variable. Having n correspond to the variable being undefined in the
   Makefiles makes for easy CONFIG_* tests.

 - Invisible n-valued bool/tristate symbols normally do not generate a
   '# CONFIG_FOO is not set' line, because user values from .config
   files have no effect on invisible symbols anyway.

Currently, there is one exception to this rule: Any bool/tristate symbol
that gets the value n through a 'default' property generates a
'# CONFIG_FOO is not set' line, even if the symbol is invisible.

Note that this only applies to explicitly given defaults, and not when
the symbol implicitly defaults to n (like bool/tristate symbols without
'default' properties do).

This is inconsistent, and seems redundant:

  - As mentioned, the '# CONFIG_FOO is not set' won't affect the symbol
    once the .config is read back in.

  - Even if the symbol is invisible at first but becomes visible later,
    there shouldn't be any harm in recalculating the default value
    rather than viewing the '# CONFIG_FOO is not set' as a previous
    user value of n.

=== Changes ===

Change sym_calc_value() to only set SYMBOL_WRITE (write to .config) for
non-n-valued 'default' properties.

Note that SYMBOL_WRITE is always set for visible symbols regardless of whether
they have 'default' properties or not, so this change only affects invisible
symbols.

This reduces the size of the x86 .config on my system by about 1% (due
to removed '# CONFIG_FOO is not set' entries).

One side effect of (and the main motivation for) this change is making
the following two definitions behave exactly the same:

	config FOO
		bool

	config FOO
		bool
		default n

With this change, neither of these will generate a
'# CONFIG_FOO is not set' line (assuming FOO isn't selected/implied).
That might make it clearer to people that a bare 'default n' is
redundant.

This change only affects generated .config files and not autoconf.h:
autoconf.h only includes #defines for non-n bool/tristate symbols.

=== Testing ===

The following testing was done with the x86 Kconfigs:

 - .config files generated before and after the change were compared to
   verify that the only difference is some '# CONFIG_FOO is not set'
   entries disappearing. A couple of these were inspected manually, and
   most turned out to be from redundant 'default n/def_bool n'
   properties.

 - The generated include/generated/autoconf.h was compared before and
   after the change and verified to be identical.

 - As a sanity check, the same modification was done to Kconfiglib.
   The Kconfiglib test suite was then run to check for any mismatches
   against the output of the C implementation.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:03:58 +09:00
Eugeniu Rosca
d9119b5925 kconfig: Print reverse dependencies in groups
Surprisingly or not, disabling a CONFIG option (which is assumed to
be unneeded) may be not so trivial. Especially it is not trivial, when
this CONFIG option is selected by a dozen of other configs. Before the
moment commit 1ccb271433 ("kconfig: make "Selected by:" and
"Implied by:" readable") popped up in v4.16-rc1, it was an absolute pain
to break down the "Selected by" reverse dependency expression in order
to identify all those configs which select (IOW *do not allow
disabling*) a certain feature (assumed to be not needed).

This patch tries to make one step further by putting at users'
fingertips the revdep top level OR sub-expressions grouped/clustered by
the tristate value they evaluate to. This should allow the users to
directly concentrate on and tackle the _active_ reverse dependencies.

To give some numbers and quantify the complexity of certain reverse
dependencies, assuming commit 617aebe6a9 ("Merge tag
'usercopy-v4.16-rc1' of
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux"), ARCH=arm64
and vanilla arm64 defconfig, here is the top 10 CONFIG options with
the highest amount of top level "||" sub-expressions/tokens that make
up the final "Selected by" reverse dependency expression.

| Config            | All revdep | Active revdep |
|-------------------|------------|---------------|
| REGMAP_I2C        | 212        | 9             |
| CRC32             | 167        | 25            |
| FW_LOADER         | 128        | 5             |
| MFD_CORE          | 124        | 9             |
| FB_CFB_IMAGEBLIT  | 114        | 2             |
| FB_CFB_COPYAREA   | 111        | 2             |
| FB_CFB_FILLRECT   | 110        | 2             |
| SND_PCM           | 103        | 2             |
| CRYPTO_HASH       | 87         | 19            |
| WATCHDOG_CORE     | 86         | 6             |

The story behind the above is that users need to visually
review/evaluate 212 expressions which *potentially* select REGMAP_I2C
in order to identify the expressions which *actually* select REGMAP_I2C,
for a particular ARCH and for a particular defconfig used.

To make this experience smoother, change the way reverse dependencies
are displayed to the user from [1] to [2].

[1] Old representation of DMA_ENGINE_RAID:
  Selected by:
  - AMCC_PPC440SPE_ADMA [=n] && DMADEVICES [=y] && (440SPe || 440SP)
  - BCM_SBA_RAID [=m] && DMADEVICES [=y] && (ARM64 [=y] || ...
  - FSL_RAID [=n] && DMADEVICES [=y] && FSL_SOC && ...
  - INTEL_IOATDMA [=n] && DMADEVICES [=y] && PCI [=y] && X86_64
  - MV_XOR [=n] && DMADEVICES [=y] && (PLAT_ORION || ARCH_MVEBU [=y] ...
  - MV_XOR_V2 [=y] && DMADEVICES [=y] && ARM64 [=y]
  - XGENE_DMA [=n] && DMADEVICES [=y] && (ARCH_XGENE [=y] || ...
  - DMATEST [=n] && DMADEVICES [=y] && DMA_ENGINE [=y]

[2] New representation of DMA_ENGINE_RAID:
  Selected by [y]:
  - MV_XOR_V2 [=y] && DMADEVICES [=y] && ARM64 [=y]
  Selected by [m]:
  - BCM_SBA_RAID [=m] && DMADEVICES [=y] && (ARM64 [=y] || ...
  Selected by [n]:
  - AMCC_PPC440SPE_ADMA [=n] && DMADEVICES [=y] && (440SPe || ...
  - FSL_RAID [=n] && DMADEVICES [=y] && FSL_SOC && ...
  - INTEL_IOATDMA [=n] && DMADEVICES [=y] && PCI [=y] && X86_64
  - MV_XOR [=n] && DMADEVICES [=y] && (PLAT_ORION || ARCH_MVEBU [=y] ...
  - XGENE_DMA [=n] && DMADEVICES [=y] && (ARCH_XGENE [=y] || ...
  - DMATEST [=n] && DMADEVICES [=y] && DMA_ENGINE [=y]

Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:03:58 +09:00
Masahiro Yamada
9a47ceec54 kconfig: clean-up reverse dependency help implementation
This commit splits out the special E_OR handling ('-' instead of '||')
into a dedicated helper expr_print_revdev().

Restore the original expr_print() prior to commit 1ccb271433
("kconfig: make "Selected by:" and "Implied by:" readable").

This makes sense because:

  - We need to chop those expressions only when printing the reverse
    dependency, and only when E_OR is encountered

  - Otherwise, it should be printed as before, so fall back to
    expr_print()

This also improves the behavior; for a single line, it was previously
displayed in the same line as "Selected by", like this:

  Selected by: A [=n] && B [=n]

This will be displayed in a new line, consistently:

  Selected by:
  - A [=n] && B [=n]

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
2018-03-26 02:03:57 +09:00
Masahiro Yamada
5ae6fcc4bb kconfig: fix line number in recursive inclusion error message
When recursive inclusion is detected, the line number of the last
'included from:' is wrong.

[Test Case]

Kconfig:
  -------->8--------
  source "Kconfig2"
  -------->8--------

Kconfig2:
  -------->8--------
  source "Kconfig3"
  -------->8--------

Kconfig3:
  -------->8--------
  source "Kconfig"
  -------->8--------

[Result]

  $ make allyesconfig
  scripts/kconfig/conf  --allyesconfig Kconfig
  Kconfig:1: recursive inclusion detected. Inclusion path:
    current file : 'Kconfig'
    included from: 'Kconfig3:1'
    included from: 'Kconfig2:1'
    included from: 'Kconfig:3'
  scripts/kconfig/Makefile:89: recipe for target 'allyesconfig' failed
  make[1]: *** [allyesconfig] Error 1
  Makefile:512: recipe for target 'allyesconfig' failed
  make: *** [allyesconfig] Error 2

where we expect

    current file : 'Kconfig'
    included from: 'Kconfig3:1'
    included from: 'Kconfig2:1'
    included from: 'Kconfig:1'

The 'iter->lineno+1' in the second fpinrtf() should be 'iter->lineno-1'.
I refactored the code to merge the two fprintf() calls.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-03 00:44:47 +09:00
Arvind Prasanna
1a90ce36c6 kconfig: Update ncurses package names for menuconfig
The package name is ncurses-devel for Redhat based distros
and libncurses-dev for Debian based distros.

Signed-off-by: Arvind Prasanna <arvindprasanna@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-02 09:20:57 +09:00
Masahiro Yamada
bf0bbdcf10 kconfig: Don't leak choice names during parsing
The named choice is not used in the kernel tree, but if it were used,
it would not be freed.

The intention of the named choice can be seen in the log of
commit 5a1aa8a1af ("kconfig: add named choice group").

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-02 09:20:55 +09:00
Masahiro Yamada
f4bc1eefc1 kconfig: set SYMBOL_AUTO to the symbol marked with defconfig_list
The 'defconfig_list' is a weird attribute.  If the '.config' is
missing, conf_read_simple() iterates over all visible defaults,
then it uses the first one for which fopen() succeeds.

config DEFCONFIG_LIST
	string
	depends on !UML
	option defconfig_list
	default "/lib/modules/$UNAME_RELEASE/.config"
	default "/etc/kernel-config"
	default "/boot/config-$UNAME_RELEASE"
	default "$ARCH_DEFCONFIG"
	default "arch/$ARCH/defconfig"

However, like other symbols, the first visible default is always
written out to the .config file.  This might be different from what
has been actually used.

For example, on my machine, the third one "/boot/config-$UNAME_RELEASE"
is opened, like follows:

  $ rm .config
  $ make oldconfig 2>/dev/null
  scripts/kconfig/conf  --oldconfig Kconfig
  #
  # using defaults found in /boot/config-4.4.0-112-generic
  #
  *
  * Restart config...
  *
  *
  * IRQ subsystem
  *
  Expose irq internals in debugfs (GENERIC_IRQ_DEBUGFS) [N/y/?] (NEW)

However, the resulted .config file contains the first one since it is
visible:

  $ grep CONFIG_DEFCONFIG_LIST .config
  CONFIG_DEFCONFIG_LIST="/lib/modules/$UNAME_RELEASE/.config"

In order to stop confusing people, prevent this CONFIG option from
being written to the .config file.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-02 09:20:44 +09:00
Masahiro Yamada
cd81fc82b9 kconfig: add xstrdup() helper
We already have xmalloc(), xcalloc(), and xrealloc(().  Add xstrdup()
as well to save tedious error handling.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-02 00:26:47 +09:00
Masahiro Yamada
523ca58b7d kconfig: remove const qualifier from sym_expand_string_value()
This function returns realloc'ed memory, so the returned pointer
must be passed to free() when done.  So, 'const' qualifier is odd.
It is allowed to modify the expanded string.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-02-10 11:31:49 +09:00
Masahiro Yamada
d717f24d8c kconfig: add xrealloc() helper
We already have xmalloc(), xcalloc().  Add xrealloc() as well
to save tedious error handling.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-02-10 11:26:04 +09:00
Masahiro Yamada
9e3e10c725 kconfig: send error messages to stderr
These messages should be directed to stderr.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-02-09 04:10:10 +09:00
Masahiro Yamada
f3ff6fb5db kconfig: echo stdin to stdout if either is redirected
If stdio is not tty, conf_askvalue() puts additional new line to
prevent prompts from being concatenated into a single line.  This
care is missing in conf_choice(), so a 'choice' prompt and the next
prompt are shown in the same line.

Move the code into xfgets() to cater to all cases.  To improve this
more, let's echo stdin to stdout.  This clarifies what keys were
input from stdio and the stdout looks like as if it were from tty.

I removed the isatty(2) check since stderr is unrelated here.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-02-09 04:10:10 +09:00
Masahiro Yamada
d2a04648a5 kconfig: remove check_stdin()
Except silentoldconfig, valid_stdin is 1, so check_stdin() is no-op.

oldconfig and silentoldconfig work almost in the same way except that
the latter generates additional files under include/.  Both ask users
for input for new symbols.

I do not know why only silentoldconfig requires stdio be tty.

  $ rm -f .config; touch .config
  $ yes "" | make oldconfig > stdout
  $ rm -f .config; touch .config
  $ yes "" | make silentoldconfig > stdout
  make[1]: *** [silentoldconfig] Error 1
  make: *** [silentoldconfig] Error 2
  $ tail -n 4 stdout
  Console input/output is redirected. Run 'make oldconfig' to update configuration.

  scripts/kconfig/Makefile:40: recipe for target 'silentoldconfig' failed
  Makefile:507: recipe for target 'silentoldconfig' failed

Redirection is useful, for example, for testing where we want to give
particular key inputs from a test file, then check the result.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-02-09 04:10:10 +09:00
Masahiro Yamada
cd58a91def kconfig: remove 'config*' pattern from .gitignnore
I could not figure out why this pattern should be ignored.
Checking commit 1e65174a33 ("Add some basic .gitignore files")
did not help.

Let's remove this pattern, then see if it is really needed.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-02-09 04:10:09 +09:00
Masahiro Yamada
4f208f3921 kconfig: show '?' prompt even if no help text is available
'make config', 'make oldconfig', etc. always receive '?' as a valid
input and show useful information even if no help text is available.

------------------------>8------------------------
foo (FOO) [N/y] (NEW) ?

There is no help available for this option.
Symbol: FOO [=n]
Type  : bool
Prompt: foo
  Defined at Kconfig:1
------------------------>8------------------------

However, '?' is not shown in the prompt if its help text is missing.
Let's show '?' all the time so that the prompt and the behavior match.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-02-09 04:10:09 +09:00
Masahiro Yamada
cb67ab2cd2 kconfig: do not write choice values when their dependency becomes n
"# CONFIG_... is not set" for choice values are wrongly written into
the .config file if they are once visible, then become invisible later.

  Test case
  ---------

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

choice
	prompt "Choice ?"
	depends on A

config CHOICE_B
	bool "Choice B"

config CHOICE_C
	bool "Choice C"

endchoice
----------------------------------------------------------------

---------------------------(.config)----------------------------
CONFIG_A=y
----------------------------------------------------------------

With the Kconfig and .config above,

  $ make config
  scripts/kconfig/conf  --oldaskconfig Kconfig
  *
  * Linux Kernel Configuration
  *
  A (A) [Y/n] n
  #
  # configuration written to .config
  #
  $ cat .config
  #
  # Automatically generated file; DO NOT EDIT.
  # Linux Kernel Configuration
  #
  # CONFIG_A is not set
  # CONFIG_CHOICE_B is not set
  # CONFIG_CHOICE_C is not set

Here,

  # CONFIG_CHOICE_B is not set
  # CONFIG_CHOICE_C is not set

should not be written into the .config file because their dependency
"depends on A" is unmet.

Currently, there is no code that clears SYMBOL_WRITE of choice values.

Clear SYMBOL_WRITE for all symbols in sym_calc_value(), then set it
again after calculating visibility.  To simplify the logic, set the
flag if they have non-n visibility, regardless of types, and regardless
of whether they are choice values or not.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-02-09 04:08:05 +09:00
Ulf Magnusson
1b9eda2e48 kconfig: Warn if help text is blank
Blank help texts are probably either a typo, a Kconfig misunderstanding,
or some kind of half-committing to adding a help text (in which case a
TODO comment would be clearer, if the help text really can't be added
right away).

Best to flag them, IMO.

Example warning:

	drivers/mmc/host/Kconfig:877: warning: 'MMC_TOSHIBA_PCI' defined with blank help text

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-02-03 00:02:19 +09:00
Linus Torvalds
562f36ed28 Kconfig updates for v4.16
A pretty big batch of Kconfig updates. I have to mention the lexer
 and parser of Kconfig are now built from real .l and .y sources.
 So, flex and bison are the requirement for building the kernel.
 Both of them (unlike gperf) have been stable for a long time. This
 change has been tested several weeks in linux-next, and I did not
 receive any problem report about this.
 
 Summary:
 
 - Add checks for mistakes, like the choice default is not in
   choice, help is doubled
 
 - Document data structure and complex code
 
 - Fix various memory leaks
 
 - Change Makefile to build lexer and parser instead of using
   pre-generated C files
 
 - Drop 'boolean' keyword, which is equivalent to 'bool'
 
 - Use default 'yy' prefix and remove unneeded Make variables
 
 - Fix gettext() check for xconfig
 
 - Announce that oldnoconfig will be finally removed
 
 - Make 'Selected by:' and 'Implied by' readable in help and
   search result
 
 - Hide silentoldconfig from 'make help' to stop confusing people
 
 - Fix misc things and cleanups
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Merge tag 'kconfig-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kconfig updates from Masahiro Yamada:
 "A pretty big batch of Kconfig updates.

  I have to mention the lexer and parser of Kconfig are now built from
  real .l and .y sources. So, flex and bison are the requirement for
  building the kernel. Both of them (unlike gperf) have been stable for
  a long time. This change has been tested several weeks in linux-next,
  and I did not receive any problem report about this.

  Summary:

   - add checks for mistakes, like the choice default is not in choice,
     help is doubled

   - document data structure and complex code

   - fix various memory leaks

   - change Makefile to build lexer and parser instead of using
     pre-generated C files

   - drop 'boolean' keyword, which is equivalent to 'bool'

   - use default 'yy' prefix and remove unneeded Make variables

   - fix gettext() check for xconfig

   - announce that oldnoconfig will be finally removed

   - make 'Selected by:' and 'Implied by' readable in help and search
     result

   - hide silentoldconfig from 'make help' to stop confusing people

   - fix misc things and cleanups"

* tag 'kconfig-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (37 commits)
  kconfig: Remove silentoldconfig from help and docs; fix kconfig/conf's help
  kconfig: make "Selected by:" and "Implied by:" readable
  kconfig: announce removal of oldnoconfig if used
  kconfig: fix make xconfig when gettext is missing
  kconfig: Clarify menu and 'if' dependency propagation
  kconfig: Document 'if' flattening logic
  kconfig: Clarify choice dependency propagation
  kconfig: Document SYMBOL_OPTIONAL logic
  kbuild: remove unnecessary LEX_PREFIX and YACC_PREFIX
  kconfig: use default 'yy' prefix for lexer and parser
  kconfig: make conf_unsaved a local variable of conf_read()
  kconfig: make xfgets() really static
  kconfig: make input_mode static
  kconfig: Warn if there is more than one help text
  kconfig: drop 'boolean' keyword
  kconfig: use bool instead of boolean for type definition attributes, again
  kconfig: Remove menu_end_entry()
  kconfig: Document important expression functions
  kconfig: Document automatic submenu creation code
  kconfig: Fix choice symbol expression leak
  ...
2018-02-01 11:45:49 -08:00
Marc Herbert
cedd55d49d kconfig: Remove silentoldconfig from help and docs; fix kconfig/conf's help
As explained by Michal Marek at https://lkml.org/lkml/2011/8/31/189
silentoldconfig has become a misnomer. It has become an internal interface
so remove it from "make help" and Documentation/ to stop confusing people
using it as seen for instance at
https://chromium-review.googlesource.com/835632 Don't remove it from
kconfig/Makefile yet not to break any (other) tool using it.

On the other hand, correct and expand its description in the help of
the (internal) scripts/kconfig/conf.c

Signed-off-by: Marc Herbert <marc.herbert@intel.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-28 05:48:31 +09:00
Petr Vorel
1ccb271433 kconfig: make "Selected by:" and "Implied by:" readable
Reverse dependency expressions can get rather unwieldy, especially if
a symbol is selected by more than a handful of other symbols. I.e. it's
possible to have near endless expressions like:
   A && B && !C || D || F && (G || H) || [...]

Chop these expressions into actually readable chunks:
   - A && B && !C
   - D
   - F && (G || H)
   - [...]

I.e. transform the top level OR tokens into newlines and prepend each
line with a minus. This makes the "Selected by:" and "Implied by:" blurb
much easier to read. This is done only if there is more than one top
level OR. "Depends on:" and "Range :" were deliberately left as they are.

Based on idea from Paul Bolle.

Suggested-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Petr Vorel <petr.vorel@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-25 21:53:00 +09:00
Masahiro Yamada
312ee68752 kconfig: announce removal of oldnoconfig if used
The 'oldnoconfig' is really confusing due to its counter-intuitive name.
It was renamed by commit fb16d8912d ("kconfig: replace 'oldnoconfig'
with 'olddefconfig', and keep the old name as an alias").

The 'oldnoconfig' has been kept as an alias for enough period of time,
and finally I am planning to remove it.  I will give people a little
more time for migration.  Meanwhile, the following message will be
displayed if oldnoconfig is used.

    WARNING: "oldnoconfig" target will be removed after Linux 4.19
              Please use "olddefconfig" instead, which is an alias.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-01-25 21:46:28 +09:00
Yaakov Selkowitz
d0fd0428ec kconfig: fix make xconfig when gettext is missing
The C-based config programs are properly guarded from a missing (or,
currently, external) libintl.h by the HOST_EXTRACFLAGS check, but
this does not help the C++-based qconf.

Signed-off-by: Yaakov Selkowitz <yselkowi@redhat.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 03:30:09 +09:00
Ulf Magnusson
b53688014e kconfig: Clarify menu and 'if' dependency propagation
It is not obvious that the last two cases refer to menus and ifs,
respectively, in the conditional that sets 'parentdep'.

Automatic submenu creation is done later, so the parent can't be a
symbol here.

No functional changes. Only comments added.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 03:30:09 +09:00
Ulf Magnusson
9d1a9e8bc1 kconfig: Document 'if' flattening logic
It is not obvious that this might refer to an 'if', making the code
pretty cryptic:

	if (menu->list && (!menu->prompt || !menu->prompt->text)) {

Kconfig keeps the 'if' menu nodes even after flattening. Reflect that in
the example to be accurate.

No functional changes. Only comments added.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 01:49:30 +09:00
Ulf Magnusson
d3465af60f kconfig: Clarify choice dependency propagation
It's easy to miss that choices are special-cased to pass on their mode
as the parent dependency.

No functional changes. Only comments added.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:32 +09:00
Ulf Magnusson
3e41ba05b6 kconfig: Document SYMBOL_OPTIONAL logic
Not obvious, especially if you don't already know how choices are
implemented.

No functional changes. Only comments added.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:32 +09:00
Masahiro Yamada
765f4cdef6 kconfig: use default 'yy' prefix for lexer and parser
Flex and Bison provide an option to change the prefix of globally-
visible symbols.  This is useful to link multiple lexers and/or
parsers into the same executable.  However, Kconfig (and any other
host programs in kernel) uses a single lexer and parser.  I do not
see a good reason to change the default 'yy' prefix.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-01-22 00:49:31 +09:00
Masahiro Yamada
84dd95d4f8 kconfig: make conf_unsaved a local variable of conf_read()
conf_unsaved is initialized by conf_read_simple(), but it is possible
to move it to conf_read() so that it can be a local variable.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:31 +09:00
Masahiro Yamada
5a3dc717b3 kconfig: make xfgets() really static
Sparse reports:
  warning: symbol 'xfgets' was not declared. Should it be static?

It is declared as static, but it is missing in the definition part.
Move the definition up and remove the forward declaration.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:30 +09:00
Masahiro Yamada
52e58a3cae kconfig: make input_mode static
Sparse reports:
  warning: symbol 'input_mode' was not declared. Should it be static?

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:30 +09:00
Ulf Magnusson
6479f327de kconfig: Warn if there is more than one help text
Avoids mistakes like in the following real-world example, where only the
final help string ("Say Y...") was used. This particular example was
fixed in commit 561b29e4ec ("media: fix media Kconfig help syntax
issues").

  config DVB_NETUP_UNIDVB
  	...
	select DVB_CXD2841ER if MEDIA_SUBDRV_AUTOSELECT
  	---help---
  	  Support for NetUP PCI express Universal DVB card.
       help
  	Say Y when you want to support NetUP Dual Universal DVB card
        ...

This now prints the following warning:

  drivers/media/pci/netup_unidvb:13: warning: 'DVB_NETUP_UNIDVB' defined with more than one help text -- only the last one will be used

Also free() any extra help strings.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:29 +09:00
Masahiro Yamada
b92d804a51 kconfig: drop 'boolean' keyword
No more users of this keyword.  Drop it according to the notice by
commit 6341e62b21 ("kconfig: use bool instead of boolean for type
definition attributes").

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Luis R. Rodriguez <mcgrof@kernel.org>
2018-01-22 00:49:29 +09:00
Ulf Magnusson
df60f4b92d kconfig: Remove menu_end_entry()
menu_end_entry() is empty and completely unused as far as I can tell:

	$ git log -G menu_end_entry --oneline
	a02f057 [PATCH] kconfig: improve error handling in the parser
	1da177e Linux-2.6.12-rc2

Last one is the initial Git commit, where menu_end_entry() is empty as
well. I couldn't find anything that redefined it on Google either.

It might be a debugging helper for setting a breakpoint after each
config, menuconfig, and comment is parsed. IMO it hurts more than it
helps in that case by making the parsing code look more complicated at a
glance than it really is, and I suspect it doesn't get used much.

Tested by running the Kconfiglib test suite, which indirectly verifies
that the .config files generated by the C implementation for each
defconfig file in the kernel stays the same.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:28 +09:00
Ulf Magnusson
0735f7e5de kconfig: Document important expression functions
Many of these functions are quite the head scratchers if you don't know
what they're trying to do. Document them.

Also make it clear which functions rewrite expressions in-place and
which return new expressions. This prevents memory errors.

No functional changes. Only comments added.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:28 +09:00
Ulf Magnusson
05cccce580 kconfig: Document automatic submenu creation code
It's tricky to figure out what it does (and how) without staring at the
code for a long time. Document it to make it more transparent.

No functional changes. Only comments added.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:28 +09:00
Ulf Magnusson
7cf33f88e2 kconfig: Fix choice symbol expression leak
When propagating dependencies from parents after parsing, an expression
node is allocated if the parent symbol is a 'choice'. This node was
never freed.

Outline of leak:

	if (sym && sym_is_choice(sym)) {
		...
		*Allocate (in this case only)*
		parentdep = expr_alloc_symbol(sym);
	} else if (parent->prompt)
		parentdep = parent->prompt->visible.expr;
	else
		parentdep = parent->dep;

	for (menu = parent->list; menu; menu = menu->next) {
		...
		*Copy*
		basedep = expr_alloc_and(expr_copy(parentdep), basedep);
		...
	}
	*parentdep lost if the parent is a choice!*

Fix by freeing 'parentdep' after the loop if the parent symbol is a
choice. Note that this only frees the expression node and not the choice
symbol itself.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 1,608 bytes in 67 blocks
	   ...

Summary after the fix:

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

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:27 +09:00
Ulf Magnusson
5b1374b3b3 kconfig: Fix expr_free() E_NOT leak
Only the E_NOT operand and not the E_NOT node itself was freed, due to
accidentally returning too early in expr_free(). Outline of leak:

	switch (e->type) {
	...
	case E_NOT:
		expr_free(e->left.expr);
		return;
	...
	}
	*Never reached, 'e' leaked*
	free(e);

Fix by changing the 'return' to a 'break'.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 44,448 bytes in 1,852 blocks
	   ...

Summary after the fix:

	LEAK SUMMARY:
	   definitely lost: 1,608 bytes in 67 blocks
	   ...

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:27 +09:00
Ulf Magnusson
ae7440ef0c kconfig: Fix automatic menu creation mem leak
expr_trans_compare() always allocates and returns a new expression,
giving the following leak outline:

	...
	*Allocate*
	basedep = expr_trans_compare(basedep, E_UNEQUAL, &symbol_no);
	...
	for (menu = parent->next; menu; menu = menu->next) {
		...
		*Copy*
		dep2 = expr_copy(basedep);
		...
		*Free copy*
		expr_free(dep2);
	}
	*basedep lost!*

Fix by freeing 'basedep' after the loop.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 344,376 bytes in 14,349 blocks
	   ...

Summary after the fix:

	LEAK SUMMARY:
	   definitely lost: 44,448 bytes in 1,852 blocks
	   ...

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:26 +09:00
Ulf Magnusson
0724a7c32a kconfig: Don't leak main menus during parsing
If a 'mainmenu' entry appeared in the Kconfig files, two things would
leak:

	- The 'struct property' allocated for the default "Linux Kernel
	  Configuration" prompt.

	- The string for the T_WORD/T_WORD_QUOTE prompt after the
	  T_MAINMENU token, allocated on the heap in zconf.l.

To fix it, introduce a new 'no_mainmenu_stmt' nonterminal that matches
if there's no 'mainmenu' and adds the default prompt. That means the
prompt only gets allocated once regardless of whether there's a
'mainmenu' statement or not, and managing it becomes simple.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 344,568 bytes in 14,352 blocks
	   ...

Summary after the fix:

	LEAK SUMMARY:
	   definitely lost: 344,440 bytes in 14,350 blocks
	   ...

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:23 +09:00
Ulf Magnusson
bc28fe1d5e kconfig: Don't leak 'option' arguments during parsing
The following strings would leak before this change:

	- option env="LEAKED"
	- option defconfig_list="LEAKED"

These come in the form of T_WORD tokens and are always allocated on the
heap in zconf.l. Free them.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 344,616 bytes in 14,355 blocks
	   ...

Summary after the fix:

	LEAK SUMMARY:
	   definitely lost: 344,568 bytes in 14,352 blocks
	   ...

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-11 01:14:01 +09:00
Ulf Magnusson
24161a6711 kconfig: Don't leak 'source' filenames during parsing
The 'source_stmt' nonterminal takes a 'prompt', which consists of either
a T_WORD or a T_WORD_QUOTE, both of which are always allocated on the
heap in zconf.l and need to have their associated strings freed. Free
them.

The existing code already makes sure to always copy the string, but add
a warning to sym_expand_string_value() to make it clear that the string
must be copied, just in case.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 387,504 bytes in 15,545 blocks
	   ...

Summary after the fix:

	LEAK SUMMARY:
	   definitely lost: 344,616 bytes in 14,355 blocks
	   ...

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-11 01:14:01 +09:00
Ulf Magnusson
26e47a3c11 kconfig: Don't leak symbol names during parsing
Prior to this fix, zconf.y did not free symbol names from zconf.l in
these contexts:

	- After T_CONFIG ('config LEAKED')
	- After T_MENUCONFIG ('menuconfig LEAKED')
	- After T_SELECT ('select LEAKED')
	- After T_IMPLY ('imply LEAKED')
	- After T_DEFAULT in a choice ('default LEAKED')

All of these come in the form of T_WORD tokens, which always have their
associated string allocated on the heap in zconf.l and need to be freed.

Fix by introducing a new nonterminal 'nonconst_symbol' which takes a
T_WORD, fetches the symbol, and then frees the T_WORD string. The
already existing 'symbol' nonterminal works the same way but also
accepts T_WORD_QUOTE, corresponding to a constant symbol. T_WORD_QUOTE
should not be accepted in any of the contexts above, so the 'symbol'
nonterminal can't be reused here.

Fetching the symbol in 'nonconst_symbol' also removes a bunch of
sym_lookup() calls from actions.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 711,571 bytes in 37,756 blocks
	   ...

Summary after the fix:

	LEAK SUMMARY:
	   definitely lost: 387,504 bytes in 15,545 blocks
           ...

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-10 23:29:51 +09:00
Nicolas Pitre
9059a3493e kconfig: fix relational operators for bool and tristate symbols
Since commit 31847b67be ("kconfig: allow use of relations other than
(in)equality") it is possible to use relational operators in Kconfig
statements. However, those operators give unexpected results when
applied to bool/tristate values:

	(n < y) = y (correct)
	(m < y) = y (correct)
	(n < m) = n (wrong)

This happens because relational operators process bool and tristate
symbols as strings and m sorts before n. It makes little sense to do a
lexicographical compare on bool and tristate values though.

Documentation/kbuild/kconfig-language.txt states that expression can have
a value of 'n', 'm' or 'y' (or 0, 1, 2 respectively for calculations).
Let's make it so for relational comparisons with bool/tristate
expressions as well and document them. If at least one symbol is an
actual string then the lexicographical compare works just as before.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-06 02:31:23 +09:00
Masahiro Yamada
29c833061c kconfig: generate lexer and parser during build instead of shipping
zconf.lex.c is generated by flex, zconf.tab.c by bison.  Instead of
running flex and bison during the kernel building, we conventionally
version-control those artifacts with _shipped suffix.

It is tedious to manually regenerate them every time we change the
real sources, zconf.l and zconf.y.

Remove the _shipped files and switch over to build-time generation
of the intermediate C files.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-12-16 11:12:54 +09:00
Masahiro Yamada
e3b03bf29d kconfig: display recursive dependency resolution hint just once
Commit 1c199f2878 ("kbuild: document recursive dependency limitation
/ resolution") probably intended to show a hint along with "recursive
dependency detected!" error, but it missed to add {...} guard, and the
hint is displayed in every loop of the dep_stack traverse, annoyingly.

This error was detected by GCC's -Wmisleading-indentation when switching
to build-time generation of lexer/parser.

scripts/kconfig/symbol.c: In function ‘sym_check_print_recursive’:
scripts/kconfig/symbol.c:1150:3: warning: this ‘if’ clause does not guard... [-Wmisleading-indentation]
   if (stack->sym == last_sym)
   ^~
scripts/kconfig/symbol.c:1153:4: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the ‘if’
    fprintf(stderr, "For a resolution refer to Documentation/kbuild/kconfig-language.txt\n");
    ^~~~~~~

I could simply add {...} to surround the three fprintf(), but I rather
chose to move the hint after the loop to make the whole message readable.

Fixes: 1c199f2878 ("kbuild: document recursive dependency limitation / resolution"
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Luis R. Rodriguez <mcgrof@kernel.org>
2017-12-16 11:12:53 +09:00
Ulf Magnusson
f77850d3fe kconfig: Clean up modules handling and fix crash
Kconfig currently doesn't handle 'm' appearing in a Kconfig file before
the modules symbol is defined (the symbol with 'option modules'). The
problem is the following code, which runs during parsing:

	/* change 'm' into 'm' && MODULES */
	if (e->left.sym == &symbol_mod)
		return expr_alloc_and(e, expr_alloc_symbol(modules_sym));

If the modules symbol has not yet been defined, modules_sym is NULL,
giving an invalid expression.

Here is a test file where both BEFORE_1 and BEFORE_2 trigger a segfault.
If the modules symbol is removed, all symbols trigger segfaults.

	config BEFORE_1
		def_tristate y if m

	if m
	config BEFORE_2
		def_tristate y
	endif

	config MODULES
		def_bool y
		option modules

	config AFTER_1
		def_tristate y if m

	if m
	config AFTER_2
		def_tristate y
	endif

Fix the issue by rewriting 'm' in menu_finalize() instead. This function
runs after parsing and is the proper place to do it. The following
existing code in conf_parse() in zconf.y ensures that the modules symbol
exists at that point:

	if (!modules_sym)
		modules_sym = sym_find( "n" );

	...

	menu_finalize(&rootmenu);

The following tests were done to ensure no functional changes for
configurations that don't reference 'm' before the modules symbol:

	- zconfdump(stdout) was run with ARCH=x86 and ARCH=arm before
	  and after the change and verified to produce identical output.
	  This function prints all symbols, choices, and menus together
	  with their properties and their dependency expressions. A
	  rewritten 'm' appears as 'm && MODULES'.

	  A small annoyance is that the assert(len != 0) in xfwrite()
	  needs to be disabled in order to use zconfdump(), because it
	  chokes on e.g. 'default ""'.

	- The Kconfiglib test suite was run to indirectly verify that
	  alldefconfig, allyesconfig, allnoconfig, and all defconfigs in
	  the kernel still generate the same final .config.

	- Valgrind was used to check for memory errors and (new) memory
	  leaks.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-12-15 08:21:37 +09:00
Ulf Magnusson
fa8cedaef8 kconfig: Clarify expression rewriting
menu_finalize() is one of the more opaque parts of Kconfig, and I need
to make some changes to it to fix an issue related to modules. Add some
comments related to expression rewriting and dependency propagation as a
review aid. They will also help other people trying to understand the
code.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-12-15 08:21:31 +09:00
Ulf Magnusson
9a826842ff kconfig: Rename menu_check_dep() to rewrite_m()
More directly describes the only thing it does.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-12-15 08:21:25 +09:00