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761 Commits

Author SHA1 Message Date
Linus Torvalds 147a89bc71 Kconfig updates for v4.17
- improve checkpatch for more precise Kconfig code checking
 
 - clarify effective selects by grouping reverse dependencies in help
 
 - do not write out '# CONFIG_FOO is not set' from invisible symbols
 
 - make oldconfig as silent as it should be
 
 - rename 'silentoldconfig' to 'syncconfig'
 
 - add unit-test framework and several test cases
 
 - warn unmet dependency of tristate symbols
 
 - make unmet dependency warnings readable, removing false positives
 
 - improve recursive include detection
 
 - use yylineno to simplify the line number tracking
 
 - misc cleanups
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Merge tag 'kconfig-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kconfig updates from Masahiro Yamada:

 - improve checkpatch for more precise Kconfig code checking

 - clarify effective selects by grouping reverse dependencies in help

 - do not write out '# CONFIG_FOO is not set' from invisible symbols

 - make oldconfig as silent as it should be

 - rename 'silentoldconfig' to 'syncconfig'

 - add unit-test framework and several test cases

 - warn unmet dependency of tristate symbols

 - make unmet dependency warnings readable, removing false positives

 - improve recursive include detection

 - use yylineno to simplify the line number tracking

 - misc cleanups

* tag 'kconfig-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (30 commits)
  kconfig: use yylineno option instead of manual lineno increments
  kconfig: detect recursive inclusion earlier
  kconfig: remove duplicated file name and lineno of recursive inclusion
  kconfig: do not include both curses.h and ncurses.h for nconfig
  kconfig: make unmet dependency warnings readable
  kconfig: warn unmet direct dependency of tristate symbols selected by y
  kconfig: tests: test if recursive inclusion is detected
  kconfig: tests: test if recursive dependencies are detected
  kconfig: tests: test randconfig for choice in choice
  kconfig: tests: test defconfig when two choices interact
  kconfig: tests: check visibility of tristate choice values in y choice
  kconfig: tests: check unneeded "is not set" with unmet dependency
  kconfig: tests: test if new symbols in choice are asked
  kconfig: tests: test automatic submenu creation
  kconfig: tests: add basic choice tests
  kconfig: tests: add framework for Kconfig unit testing
  kbuild: add PYTHON2 and PYTHON3 variables
  kconfig: remove redundant streamline_config.pl prerequisite
  kconfig: rename silentoldconfig to syncconfig
  kconfig: invoke oldconfig instead of silentoldconfig from local*config
  ...
2018-04-03 16:28:01 -07:00
Masahiro Yamada 18492685e4 kconfig: use yylineno option instead of manual lineno increments
Tracking the line number by hand is error-prone since you need to
increment it in every \n matching pattern.

If '%option yylineno' is set, flex defines 'yylineno' to contain the
current line number and automatically updates it each time it reads a
\n character.  This is much more convenient although the lexer does
not initializes yylineno, so you need to set it to 1 each time you
start reading a new file, and restore it you go back to the previous
file.

I tested this with DEBUG_PARSE, and confirmed the same dump message
was produced.

I removed the perf-report option.  Otherwise, I see the following
message:
  %option yylineno entails a performance penalty ONLY on rules that
  can match newline characters

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:04:07 +09:00
Masahiro Yamada 379a8eb8eb kconfig: detect recursive inclusion earlier
Currently, the recursive inclusion is not detected when the offending
file is about to be included; it is detected the offending file is
about to include the *next* file.  This is because the detection loop
does not involve the file being included.

Do this check against the file that is about to be included so that
the recursive inclusion is detected before unneeded parsing happens.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:04:07 +09:00
Masahiro Yamada 32a94b8b0c kconfig: remove duplicated file name and lineno of recursive inclusion
As in the unit test, the error message for the recursive inclusion
looks like this:

  Kconfig.inc1:4: recursive inclusion detected. Inclusion path:
    current file : 'Kconfig.inc1'
    included from: 'Kconfig.inc3:1'
    included from: 'Kconfig.inc2:3'
    included from: 'Kconfig.inc1:4'

The 'Kconfig.inc1:4' is duplicated in the first and last lines.
Also, the single quotes do not help readability.

Change the message like follows:

  Recursive inclusion detected.
  Inclusion path:
    current file : Kconfig.inc1
    included from: Kconfig.inc3:1
    included from: Kconfig.inc2:3
    included from: Kconfig.inc1:4

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:04:06 +09:00
Masahiro Yamada 26561514cc kconfig: do not include both curses.h and ncurses.h for nconfig
nconf.h includes <curses.h> and "ncurses.h", but it does not need to
include both.  Generally, it should fall back to curses.h only when
ncurses.h is not found.  But, looks like it has never happened;
these includes have been here for many years since commit 692d97c380
("kconfig: new configuration interface (nconfig)"), and nobody has
complained about hard-coding of ncurses.h .  Let's simply drop the
curses.h inclusion.

I replaced "ncurses.h" with <ncurses.h> since it is not a local file.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:04:06 +09:00
Masahiro Yamada f8f69dc0b4 kconfig: make unmet dependency warnings readable
Currently, the unmet dependency warnings end up with endlessly long
expressions, most of which are false positives.

Here is test code to demonstrate how it currently works.

[Test Case]

  config DEP1
          def_bool y

  config DEP2
          bool "DEP2"

  config A
          bool "A"
          select E

  config B
          bool "B"
          depends on DEP2
          select E

  config C
          bool "C"
          depends on DEP1 && DEP2
          select E

  config D
          def_bool n
          select E

  config E
          bool
          depends on DEP1 && DEP2

[Result]

  $ make config
  scripts/kconfig/conf  --oldaskconfig Kconfig
  *
  * Linux Kernel Configuration
  *
  DEP2 (DEP2) [N/y/?] (NEW) n
  A (A) [N/y/?] (NEW) y
  warning: (A && B && D) selects E which has unmet direct
  dependencies (DEP1 && DEP2)

Here, I see some points to be improved.

First, '(A || B || D)' would make more sense than '(A && B && D)'.
I am not sure if this is intentional, but expr_simplify_unmet_dep()
turns OR expressions into AND, like follows:

        case E_OR:
                return expr_alloc_and(

Second, we see false positives.  'A' is a real unmet dependency.
'B' is false positive because 'DEP1' is fixed to 'y', and 'B' depends
on 'DEP2'.  'C' was correctly dropped by expr_simplify_unmet_dep().
'D' is also false positive because it has no chance to be enabled.
Current expr_simplify_unmet_dep() cannot avoid those false positives.

After all, I decided to use the same helpers as used for printing
reverse dependencies in the help.

With this commit, unreadable warnings (most of the reported symbols are
false positives) in the real world:

$ make ARCH=score allyesconfig
scripts/kconfig/conf  --allyesconfig Kconfig
warning: (HWSPINLOCK_QCOM && AHCI_MTK && STMMAC_PLATFORM &&
 DWMAC_IPQ806X && DWMAC_LPC18XX && DWMAC_OXNAS && DWMAC_ROCKCHIP &&
 DWMAC_SOCFPGA && DWMAC_STI && TI_CPSW && PINCTRL_GEMINI &&
 PINCTRL_OXNAS && PINCTRL_ROCKCHIP && PINCTRL_DOVE &&
 PINCTRL_ARMADA_37XX && PINCTRL_STM32 && S3C2410_WATCHDOG &&
 VIDEO_OMAP3 && VIDEO_S5P_FIMC && USB_XHCI_MTK && RTC_DRV_AT91SAM9 &&
 LPC18XX_DMAMUX && VIDEO_OMAP4 && COMMON_CLK_GEMINI &&
 COMMON_CLK_ASPEED && COMMON_CLK_NXP && COMMON_CLK_OXNAS &&
 COMMON_CLK_BOSTON && QCOM_ADSP_PIL && QCOM_Q6V5_PIL && QCOM_GSBI &&
 ATMEL_EBI && ST_IRQCHIP && RESET_IMX7 && PHY_HI6220_USB &&
 PHY_RALINK_USB && PHY_ROCKCHIP_PCIE && PHY_DA8XX_USB) selects
 MFD_SYSCON which has unmet direct dependencies (HAS_IOMEM)
warning: (PINCTRL_AT91 && PINCTRL_AT91PIO4 && PINCTRL_OXNAS &&
 PINCTRL_PISTACHIO && PINCTRL_PIC32 && PINCTRL_MESON &&
 PINCTRL_NOMADIK && PINCTRL_MTK && PINCTRL_MT7622 && GPIO_TB10X)
 selects OF_GPIO which has unmet direct dependencies (GPIOLIB && OF &&
 HAS_IOMEM)
warning: (FAULT_INJECTION_STACKTRACE_FILTER && LATENCYTOP && LOCKDEP)
 selects FRAME_POINTER which has unmet direct dependencies
 (DEBUG_KERNEL && (CRIS || M68K || FRV || UML || SUPERH || BLACKFIN ||
 MN10300 || METAG) || ARCH_WANT_FRAME_POINTERS)

will be turned into:

$ make ARCH=score allyesconfig
scripts/kconfig/conf  --allyesconfig Kconfig

WARNING: unmet direct dependencies detected for MFD_SYSCON
  Depends on [n]: HAS_IOMEM [=n]
  Selected by [y]:
  - PINCTRL_STM32 [=y] && PINCTRL [=y] && (ARCH_STM32 ||
 COMPILE_TEST [=y]) && OF [=y]
  - RTC_DRV_AT91SAM9 [=y] && RTC_CLASS [=y] && (ARCH_AT91 ||
 COMPILE_TEST [=y])
  - RESET_IMX7 [=y] && RESET_CONTROLLER [=y]
  - PHY_HI6220_USB [=y] && (ARCH_HISI && ARM64 ||
 COMPILE_TEST [=y])
  - PHY_RALINK_USB [=y] && (RALINK || COMPILE_TEST [=y])
  - PHY_ROCKCHIP_PCIE [=y] && (ARCH_ROCKCHIP && OF [=y] ||
 COMPILE_TEST [=y])

WARNING: unmet direct dependencies detected for OF_GPIO
  Depends on [n]: GPIOLIB [=y] && OF [=y] && HAS_IOMEM [=n]
  Selected by [y]:
  - PINCTRL_MTK [=y] && PINCTRL [=y] && (ARCH_MEDIATEK ||
 COMPILE_TEST [=y]) && OF [=y]
  - PINCTRL_MT7622 [=y] && PINCTRL [=y] && (ARCH_MEDIATEK ||
 COMPILE_TEST [=y]) && OF [=y] && (ARM64 || COMPILE_TEST [=y])

WARNING: unmet direct dependencies detected for FRAME_POINTER
  Depends on [n]: DEBUG_KERNEL [=y] && (CRIS || M68K || FRV || UML ||
 SUPERH || BLACKFIN || MN10300 || METAG) || ARCH_WANT_FRAME_POINTERS [=n]
  Selected by [y]:
  - LATENCYTOP [=y] && DEBUG_KERNEL [=y] && STACKTRACE_SUPPORT [=y] &&
 PROC_FS [=y] && !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND &&
 !ARC && !X86

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Petr Vorel <petr.vorel@gmail.com>
2018-03-26 02:04:06 +09:00
Masahiro Yamada f622f82795 kconfig: warn unmet direct dependency of tristate symbols selected by y
Commit 246cf9c26b ("kbuild: Warn on selecting symbols with unmet
direct dependencies") forcibly promoted ->dir_dep.tri to yes from mod.
So, the unmet direct dependencies of tristate symbols are not reported.

[Test Case]

  config MODULES
          def_bool y
          option modules

  config A
          def_bool y
          select B

  config B
          tristate "B"
          depends on m

This causes unmet dependency because 'B' is forced 'y' ignoring
'depends on m'.  This should be warned.

On the other hand, the following case ('B' is bool) should not be
warned, so 'depends on m' for bool symbols should be naturally treated
as 'depends on y'.

[Test Case2 (not unmet dependency)]

  config MODULES
          def_bool y
          option modules

  config A
          def_bool y
          select B

  config B
          bool "B"
          depends on m

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:04:05 +09:00
Masahiro Yamada e2c75e7667 kconfig: tests: test if recursive inclusion is detected
If recursive inclusion is detected, it should fail with error
messages.  Test this.

This also tests the line numbers in the error message, fixed by
commit 5ae6fcc4bb ("kconfig: fix line number in recursive inclusion
error message").

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-26 02:04:05 +09:00
Masahiro Yamada 29c434f367 kconfig: tests: test if recursive dependencies are detected
Recursive dependency should be detected and warned.  Test this.

This indirectly tests the line number increments.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-26 02:04:04 +09:00
Masahiro Yamada 3e4888c2e3 kconfig: tests: test randconfig for choice in choice
Commit 3b9a19e089 ("kconfig: loop as long as we changed some symbols
in randconfig") fixed randconfig where a choice contains a sub-choice.
Prior to that commit, the sub-choice values were not set.

I am not sure whether this is an intended feature or just something
people discovered works, but it is used in the real world;
drivers/usb/gadget/legacy/Kconfig is source'd in a choice context,
then creates a sub-choice in it.

For the test case in this commit, there are 3 possible results.

Case 1:
  CONFIG_A=y
  # CONFIG_B is not set

Case 2:
  # CONFIG_A is not set
  CONFIG_B=y
  CONFIG_C=y
  # CONFIG_D is not set

Case 3:
  # CONFIG_A is not set
  CONFIG_B=y
  # CONFIG_C is not set
  CONFIG_D=y
  CONFIG_E=y

So, this test iterates several times, and checks if the result is
either of the three.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-26 02:04:04 +09:00
Masahiro Yamada beaaddb625 kconfig: tests: test defconfig when two choices interact
Commit fbe98bb9ed ("kconfig: Fix defconfig when one choice menu
selects options that another choice menu depends on") fixed defconfig
when two choices interact (i.e. calculating the visibility of a choice
requires to calculate another choice).

The test code in that commit log was based on the real world example,
and complicated.  So, I shrunk it down to the following:

defconfig.choice:
---8<---
CONFIG_CHOICE_VAL0=y
---8<---

---8<---
config MODULES
        def_bool y
        option modules

choice
        prompt "Choice"

config CHOICE_VAL0
        tristate "Choice 0"

config CHOICE_VAL1
        tristate "Choice 1"

endchoice

choice
        prompt "Another choice"
        depends on CHOICE_VAL0

config DUMMY
        bool "dummy"

endchoice
---8<---

Prior to commit fbe98bb9ed,

  $ scripts/kconfig/conf --defconfig=defconfig.choice Kconfig.choice

resulted in:

  CONFIG_MODULES=y
  CONFIG_CHOICE_VAL0=m
  # CONFIG_CHOICE_VAL1 is not set
  CONFIG_DUMMY=y

where the expected result would be:

  CONFIG_MODULES=y
  CONFIG_CHOICE_VAL0=y
  # CONFIG_CHOICE_VAL1 is not set
  CONFIG_DUMMY=y

Roughly, this weird behavior happened like this:

Symbols are calculated a couple of times.  First, all symbols are
calculated in conf_read().  The first 'choice' is evaluated to 'y'
due to the SYMBOL_DEF_USER flag, but sym_calc_choice() clears it
unless all of its choice values are explicitly set by the user.

conf_set_all_new_symbols() clears all SYMBOL_VALID flags.  Then, only
choices are calculated.  Here, the SYMBOL_DEF_USER for the first choice
has been forgotten, so it is evaluated to 'm'.  set_all_choice_values()
sets SYMBOL_DEF_USER again to choice symbols.

When calculating the second choice, due to 'depends on CHOICE_VAL0',
it triggers the calculation of CHOICE_VAL0.  As a result, SYMBOL_VALID
is set for CHOICE_VAL0.

Symbols except choices get the final chance of re-calculation in
conf_write().  In a normal case, CHOICE_VAL0 would be re-calculated,
then the first choice would be indirectly re-calculated with the
SYMBOL_DEF_USER which has been recalled by set_all_choice_values(),
which would be evaluated to 'y'.  But, in this case, CHOICE_VAL0 has
already been marked as SYMBOL_VALID, so this re-calculation does not
happen.  Then, =m from the conf_set_all_new_symbols() phase is written
out to the .config file.

Add a unit test for this naive case.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-26 02:04:04 +09:00
Masahiro Yamada ee23661065 kconfig: tests: check visibility of tristate choice values in y choice
If tristate choice values depend on symbols set to 'm', they should be
hidden when the choice containing them is changed from 'm' to 'y'
(i.e. exclusive choice).

This issue was fixed by commit fa64e5f6a3 ("kconfig/symbol.c: handle
choice_values that depend on 'm' symbols").

Add a test case to avoid regression.

For the input in this unit test, there is a room for argument if
"# CONFIG_CHOICE1 is not set" should be written to the .config file.

After commit fa64e5f6a3, this line was written to the .config file.

With commit cb67ab2cd2 ("kconfig: do not write choice values when
their dependency becomes n"), it is not written now.

In this test, "# CONFIG_CHOICE1 is not set" is don't care.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-26 02:04:03 +09:00
Masahiro Yamada 930c429a65 kconfig: tests: check unneeded "is not set" with unmet dependency
Commit cb67ab2cd2 ("kconfig: do not write choice values when their
dependency becomes n") fixed a problem where "# CONFIG_... is not set"
for choice values are wrongly written into the .config file when they
are once visible, then become invisible later.

Add a test for this naive case.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-26 02:04:03 +09:00
Masahiro Yamada b76960c0f6 kconfig: tests: test if new symbols in choice are asked
If new choice values are added with new dependency, and they become
visible during user configuration, oldconfig should recognize them
as (NEW), and ask the user for choice.

This issue was fixed by commit 5d09598d48 ("kconfig: fix new choices
being skipped upon config update").

This is a subtle corner case.  Add a test case to avoid breakage.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-26 02:04:03 +09:00
Masahiro Yamada 49ac3c0c3a kconfig: tests: test automatic submenu creation
If a symbols has dependency on the preceding symbol, the menu entry
should become the submenu of the preceding one, and displayed with
deeper indentation.

This is done by restructuring the menu tree in menu_finalize().
It is a bit complicated computation, so let's add a test case.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-26 02:04:02 +09:00
Masahiro Yamada 1903c51190 kconfig: tests: add basic choice tests
The calculation of 'choice' is a bit complicated part in Kconfig.

The behavior of 'y' choice is intuitive.  If choice values are tristate,
the choice can be 'm' where each value can be enabled independently.
Also, if a choice is marked as 'optional', the whole choice can be
invisible.

Test basic functionality of choice.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-26 02:04:02 +09:00
Masahiro Yamada 022a4bf6b5 kconfig: tests: add framework for Kconfig unit testing
Many parts in Kconfig are so cryptic and need refactoring.  However,
its complexity prevents us from moving forward.  There are several
naive corner cases where it is difficult to notice breakage.  If
those are covered by unit tests, we will be able to touch the code
with more confidence.

Here is a simple test framework based on pytest.  The conftest.py
provides a fixture useful to run commands such as 'oldaskconfig' etc.
and to compare the resulted .config, stdout, stderr with expectations.

How to add test cases?
----------------------

For each test case, you should create a subdirectory under
scripts/kconfig/tests/ (so test cases are separated from each other).
Every test case directory should contain the following files:

 - __init__.py: describes test functions
 - Kconfig: the top level Kconfig file for the test

To do a useful job, test cases generally need additional data like
input .config and information about expected results.

How to run tests?
-----------------

You need python3 and pytest.  Then, run "make testconfig".  O= option
is supported.  If V=1 is given, detailed logs captured during tests
are displayed.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-26 02:04:01 +09:00
Ulf Magnusson 2a61625835 kconfig: remove redundant streamline_config.pl prerequisite
The local{yes,mod}config targets currently have streamline_config.pl as
a prerequisite. This is redundant, because streamline_config.pl is a
checked-in file with no prerequisites.

Remove the prerequisite and reference streamline_config.pl directly in
the recipe of the rule instead.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:04:01 +09:00
Masahiro Yamada 911a91c39c kconfig: rename silentoldconfig to syncconfig
As commit cedd55d49d ("kconfig: Remove silentoldconfig from help
and docs; fix kconfig/conf's help") mentioned, 'silentoldconfig' is a
historical misnomer.  That commit removed it from help and docs since
it is an internal interface.  If so, it should be allowed to rename
it to something more intuitive.  'syncconfig' is the one I came up
with because it updates the .config if necessary, then synchronize
include/generated/autoconf.h and include/config/* with it.

You should not manually invoke 'silentoldcofig'.  Display warning if
used in case existing scripts are doing wrong.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-26 02:04:00 +09:00
Masahiro Yamada 81d2bc2273 kconfig: invoke oldconfig instead of silentoldconfig from local*config
The purpose of local{yes,mod}config is to arrange the .config file
based on actually loaded modules.  It is unnecessary to update
include/generated/autoconf.h and include/config/* stuff here.
They will be updated as needed during the build.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-26 02:04:00 +09:00
Masahiro Yamada 2aad9b8962 kconfig: hide irrelevant sub-menus for oldconfig
Historically, "make oldconfig" has changed its behavior several times,
quieter or louder.  (I attached the history below.)  Currently, it is
not as quiet as it should be.  This commit addresses it.

  Test Case
  ---------

---------------------------(Kconfig)----------------------------
menu "menu"

config FOO
        bool "foo"

menu "sub menu"

config BAR
        bool "bar"

endmenu

endmenu

menu "sibling menu"

config BAZ
        bool "baz"

endmenu
----------------------------------------------------------------

---------------------------(.config)----------------------------
CONFIG_BAR=y
CONFIG_BAZ=y
----------------------------------------------------------------

With the Kconfig and .config above, "make silentoldconfig" and
"make oldconfig" work differently, like follows:

  $ make silentoldconfig
  scripts/kconfig/conf  --silentoldconfig Kconfig
  *
  * Restart config...
  *
  *
  * menu
  *
  foo (FOO) [N/y/?] (NEW) y
  #
  # configuration written to .config
  #

  $ make oldconfig
  scripts/kconfig/conf  --oldconfig Kconfig
  *
  * Restart config...
  *
  *
  * menu
  *
  foo (FOO) [N/y/?] (NEW) y
  *
  * sub menu
  *
  bar (BAR) [Y/n/?] y
  #
  # configuration written to .config
  #

Both hide "sibling node" since it is irrelevant.  The difference is
that silentoldconfig hides "sub menu" whereas oldconfig does not.
The behavior of silentoldconfig is preferred since the "sub menu"
does not contain any new symbol.

The root cause is in conf().  There are three input modes that can
call conf(); oldaskconfig, oldconfig, and silentoldconfig.

Everytime conf() encounters a menu entry, it calls check_conf() to
check if it contains new symbols.  If no new symbol is found, the
menu is just skipped.

Currently, this happens only when input_mode == silentoldconfig.
The oldaskconfig enters into the check_conf() loop as silentoldconfig,
so oldaskconfig works likewise for the second loop or later, but it
never happens for oldconfig.  So, irrelevant sub-menus are shown for
oldconfig.

Change the test condition to "input_mode != oldaskconfig".  This is
false only for the first loop of oldaskconfig; it must ask the user
all symbols, so no need to call check_conf().

  History of oldconfig
  --------------------

[0] Originally, "make oldconfig" was as loud as "make config"  (It
    showed the entire .config file)

[1] Commit cd9140e1e7 ("kconfig: make oldconfig is now less chatty")
    made oldconfig quieter, but it was still less quieter than
    silentoldconfig.  (oldconfig did not hide sub-menus)

[2] Commit 204c96f609 ("kconfig: fix silentoldconfig") changed
    the input_mode of oldconfig to "ask_silent" from "ask_new".
    So, oldconfig really became as quiet as silentoldconfig.
    (oldconfig hided irrelevant sub-menus)

[3] Commit 4062f1a4c0 ("kconfig: use long options in conf") made
    oldconfig as loud as [0] due to misconversion.

[4] Commit 1482834971 ("kconfig: fix make oldconfig") addressed
    the misconversion of [3], but it made oldconfig quieter only to
    the same level as [1], not [2].

This commit is restoring the behavior of [2].

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 99f0b6578b kconfig: remove redundant input_mode test for check_conf() loop
check_conf() never increments conf_cnt for listnewconfig, so conf_cnt
is always zero.

In other words, conf_cnt is not zero, "input_mode != listnewconfig"
is met.

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 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 07a422bb21 kbuild: restore autoksyms.h touch to the top Makefile
Commit d3fc425e81 ("kbuild: make sure autoksyms.h exists early")
moved the code that touches autoksyms.h to scripts/kconfig/Makefile
with obscure reason.

From Nicolas' comment [1], he did not seem to be sure about the root
cause.

I guess I figured it out, so here is a fix-up I think is more correct.
According to the error log in the original post [2], the build failed
in scripts/mod/devicetable-offsets.c

scripts/mod/Makefile is descended from scripts/Makefile, which is
invoked from the top-level Makefile by the 'scripts' target.

To build vmlinux and/or modules, Kbuild descend into $(vmlinux-dirs).
This depends on 'prepare' and 'scripts' as follows:

  $(vmlinux-dirs): prepare scripts

Because there is no dependency between 'prepare' and 'scripts', the
parallel building can execute them simultaneously.

'prepare' depends on 'prepare1', which touched autoksyms.h, while
'scripts' descends into script/, then scripts/mod/, which needs
<generated/autoksyms.h> if CONFIG_TRIM_UNUSED_KSYMS.  It was the
reason of the race.

I am not happy to have unrelated code in the Kconfig Makefile, so
getting it back to the top Makefile.

I removed the standalone test target because I want to use it to
create an empty autoksyms.h file.  Here is a little improvement;
unnecessary autoksyms.h is not created when CONFIG_TRIM_UNUSED_KSYMS
is disabled.

[1] https://lkml.org/lkml/2016/11/30/734
[2] https://lkml.org/lkml/2016/11/30/531

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
2018-03-26 02:01:22 +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