kconfig: document the positional argument in the help message

The positional argument specifies the top-level Kconfig. Include this
information in the help message.

Signed-off-by: Masahiro Yamada <

kconfig: document the positional argument in the help message

The positional argument specifies the top-level Kconfig. Include this
information in the help message.

Signed-off-by: Masahiro Yamada <[email protected]>

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kconfig: remove sym_get_choice_value()

sym_get_choice_value(menu->sym) is equivalent to sym_calc_choice(menu).

Convert all call sites of sym_get_choice_value() and then remove it.

Signed-off-by: M

kconfig: remove sym_get_choice_value()

sym_get_choice_value(menu->sym) is equivalent to sym_calc_choice(menu).

Convert all call sites of sym_get_choice_value() and then remove it.

Signed-off-by: Masahiro Yamada <[email protected]>

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kconfig: refactor choice value calculation

Handling choices has always been in a PITA in Kconfig.

For example, fixes and reverts were repeated for randconfig with
KCONFIG_ALLCONFIG:

- 422c809f03f

kconfig: refactor choice value calculation

Handling choices has always been in a PITA in Kconfig.

For example, fixes and reverts were repeated for randconfig with
KCONFIG_ALLCONFIG:

- 422c809f03f0 ("kconfig: fix randomising choice entries in presence of KCONFIG_ALLCONFIG")
- 23a5dfdad22a ("Revert "kconfig: fix randomising choice entries in presence of KCONFIG_ALLCONFIG"")
- 8357b48549e1 ("kconfig: fix randomising choice entries in presence of KCONFIG_ALLCONFIG")
- 490f16171119 ("Revert "kconfig: fix randomising choice entries in presence of KCONFIG_ALLCONFIG"")

As these commits pointed out, randconfig does not randomize choices when
KCONFIG_ALLCONFIG is used. This issue still remains.

[Test Case]

choice
prompt "choose"

config A
bool "A"

config B
bool "B"

endchoice

$ echo > all.config
$ make KCONFIG_ALLCONFIG=1 randconfig

The output is always as follows:

CONFIG_A=y
# CONFIG_B is not set

Not only randconfig, but other all*config variants are also broken with
KCONFIG_ALLCONFIG.

With the same Kconfig,

$ echo '# CONFIG_A is not set' > all.config
$ make KCONFIG_ALLCONFIG=1 allyesconfig

You will get this:

CONFIG_A=y
# CONFIG_B is not set

This is incorrect because it does not respect all.config.

The correct output should be:

# CONFIG_A is not set
CONFIG_B=y

To handle user inputs more accurately, this commit refactors the code
based on the following principles:

- When a user value is given, Kconfig must set it immediately.
Do not defer it by setting SYMBOL_NEED_SET_CHOICE_VALUES.

- The SYMBOL_DEF_USER flag must not be cleared, unless a new config
file is loaded. Kconfig must not forget user inputs.

In addition, user values for choices must be managed with priority.
If user inputs conflict within a choice block, the newest value wins.
The values given by randconfig have lower priority than explicit user
inputs.

This commit implements it by using a linked list. Every time a choice
block gets a new input, it is moved to the top of the list.

Let me explain how it works.

Let's say, we have a choice block that consists of five symbols:
A, B, C, D, and E.

Initially, the linked list looks like this:

A(=?) --> B(=?) --> C(=?) --> D(=?) --> E(=?)

Suppose randconfig is executed with the following KCONFIG_ALLCONFIG:

CONFIG_C=y
# CONFIG_A is not set
CONFIG_D=y

First, CONFIG_C=y is read. C is set to 'y' and moved to the top.

C(=y) --> A(=?) --> B(=?) --> D(=?) --> E(=?)

Next, '# CONFIG_A is not set' is read. A is set to 'n' and moved to
the top.

A(=n) --> C(=y) --> B(=?) --> D(=?) --> E(=?)

Then, 'CONFIG_D=y' is read. D is set to 'y' and moved to the top.

D(=y) --> A(=n) --> C(=y) --> B(=?) --> E(=?)

Lastly, randconfig shuffles the order of the remaining symbols,
resulting in:

D(=y) --> A(=n) --> C(=y) --> B(=y) --> E(=y)
or
D(=y) --> A(=n) --> C(=y) --> E(=y) --> B(=y)

When calculating the output, the linked list is traversed and the first
visible symbol with 'y' is taken. In this case, it is D if visible.

If D is hidden by 'depends on', the next node, A, is examined. Since
it is already specified as 'n', it is skipped. Next, C is checked, and
selected if it is visible.

If C is also invisible, either B or E is chosen as a result of the
randomization.

If B and E are also invisible, the linked list is traversed in the
reverse order, and the least prioritized 'n' symbol is chosen. It is
A in this case.

Now, Kconfig remembers all user values. This is a big difference from
the previous implementation, where Kconfig would forget CONFIG_C=y when
CONFIG_D=y appeared in the same input file.

The new appaorch respects user-specified values as much as possible.

Signed-off-by: Masahiro Yamada <[email protected]>

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kconfig: introduce choice_set_value() helper

Currently, sym_set_tristate_value() is used to set 'y' to a choice
member, which is confusing because it not only sets 'y' to the given
symbol but also t

kconfig: introduce choice_set_value() helper

Currently, sym_set_tristate_value() is used to set 'y' to a choice
member, which is confusing because it not only sets 'y' to the given
symbol but also tweaks flags of other symbols as a side effect.

Add a dedicated function for setting the value of the given choice.

Signed-off-by: Masahiro Yamada <[email protected]>

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kconfig: refactor conf_set_all_new_symbols() to reduce indentation level

The outer switch statement can be avoided by continue'ing earlier the
loop when the symbol type is neither S_BOOLEAN nor S_TR

kconfig: refactor conf_set_all_new_symbols() to reduce indentation level

The outer switch statement can be avoided by continue'ing earlier the
loop when the symbol type is neither S_BOOLEAN nor S_TRISTATE.

Remove it to reduce the indentation level by one. In addition, avoid
the repetition of sym->def[S_DEF_USER].tri.

No functional change intended.

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Nicolas Schier <[email protected]>

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kconfig: remove tristate choice support

I previously submitted a fix for a bug in the choice feature [1], where
I mentioned, "Another (much cleaner) approach would be to remove the
tristate choice s

kconfig: remove tristate choice support

I previously submitted a fix for a bug in the choice feature [1], where
I mentioned, "Another (much cleaner) approach would be to remove the
tristate choice support entirely".

There are more issues in the tristate choice feature. For example, you
can observe a couple of bugs in the following test code.

[Test Code]

config MODULES
def_bool y
modules

choice
prompt "tristate choice"
default A

config A
tristate "A"

config B
tristate "B"

endchoice

Bug 1: the 'default' property is not correctly processed

'make alldefconfig' produces:

CONFIG_MODULES=y
# CONFIG_A is not set
# CONFIG_B is not set

However, the correct output should be:

CONFIG_MODULES=y
CONFIG_A=y
# CONFIG_B is not set

The unit test file, scripts/kconfig/tests/choice/alldef_expected_config,
is wrong as well.

Bug 2: choice members never get 'y' with randconfig

For the test code above, the following combinations are possible:

A B
(1) y n
(2) n y
(3) m m
(4) m n
(5) n m
(6) n n

'make randconfig' never produces (1) or (2).

These bugs are fixable, but a more critical problem is the lack of a
sensible syntax to specify the default for the tristate choice.
The default for the choice must be one of the choice members, which
cannot specify any of the patterns (3) through (6) above.

In addition, I have never seen it being used in a useful way.

The following commits removed unnecessary use of tristate choices:

- df8df5e4bc37 ("usb: get rid of 'choice' for legacy gadget drivers")
- bfb57ef0544a ("rapidio: remove choice for enumeration")

This commit removes the tristate choice support entirely, which allows
me to delete a lot of code, making further refactoring easier.

Note:
This includes the revert of commit fa64e5f6a35e ("kconfig/symbol.c:
handle choice_values that depend on 'm' symbols"). It was suspicious
because it did not address the root cause but introduced inconsistency
in visibility between choice members and other symbols.

[1]: https://lore.kernel.org/linux-kbuild/[email protected]/T/#m0a1bb6992581462ceca861b409bb33cb8fd7dbae

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Nicolas Schier <[email protected]>

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kconfig: turn conf_choice() into void function

The return value of conf_choice() is not used.

Signed-off-by: Masahiro Yamada <[email protected]>

kconfig: remove unneeded if-conditional in conf_choice()

All symbols except choices have a name.

child->sym->name never becomes NULL inside choice blocks.

Signed-off-by: Masahiro Yamada <masahiroy

kconfig: remove unneeded if-conditional in conf_choice()

All symbols except choices have a name.

child->sym->name never becomes NULL inside choice blocks.

Signed-off-by: Masahiro Yamada <[email protected]>

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kconfig: do not reparent the menu inside a choice block

The boolean 'choice' is used to list exclusively selected config
options.

You must not add a dependency between choice members, because such

kconfig: do not reparent the menu inside a choice block

The boolean 'choice' is used to list exclusively selected config
options.

You must not add a dependency between choice members, because such a
dependency would create an invisible entry.

In the following test case, it is impossible to choose 'C'.

[Test Case 1]

choice
prompt "Choose one, but how to choose C?"

config A
bool "A"

config B
bool "B"

config C
bool "C"
depends on A

endchoice

Hence, Kconfig shows the following error message:

Kconfig:1:error: recursive dependency detected!
Kconfig:1: choice <choice> contains symbol C
Kconfig:10: symbol C is part of choice A
Kconfig:4: symbol A is part of choice <choice>
For a resolution refer to Documentation/kbuild/kconfig-language.rst
subsection "Kconfig recursive dependency limitations"

However, Kconfig does not report anything for the following similar code:

[Test Case 2]

choice
prompt "Choose one, but how to choose B?"

config A
bool "A"

config B
bool "B"
depends on A

config C
bool "C"

endchoice

This is because menu_finalize() reparents the menu tree when an entry
depends on the preceding one.

With reparenting, the menu tree:

choice
|- A
|- B
\- C

... will be transformed into the following structure:

choice
|- A
| \- B
\- C

Consequently, Kconfig considers only 'A' and 'C' as choice members.
This behavior is awkward. The second test case should be an error too.

This commit stops reparenting inside a choice.

Signed-off-by: Masahiro Yamada <[email protected]>

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kconfig: use generic macros to implement symbol hashtable

Use helper macros in hashtable.h for generic hashtable implementation.

We can git rid of the hash head index of for_all_symbols().

Signed-

kconfig: use generic macros to implement symbol hashtable

Use helper macros in hashtable.h for generic hashtable implementation.

We can git rid of the hash head index of for_all_symbols().

Signed-off-by: Masahiro Yamada <[email protected]>

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kconfig: WERROR unmet symbol dependency

When KCONFIG_WERROR env variable is set treat unmet direct
symbol dependency as a terminal condition (error).

Suggested-by: Stefan Reinauer <reinauer@google.

kconfig: WERROR unmet symbol dependency

When KCONFIG_WERROR env variable is set treat unmet direct
symbol dependency as a terminal condition (error).

Suggested-by: Stefan Reinauer <[email protected]>
Signed-off-by: Sergey Senozhatsky <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

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Kconfig: remove sym_set_choice_value

sym_set_choice_value could be removed and directly call
sym_set_tristate_value instead.

Signed-off-by: Zeng Heng <[email protected]>
Suggested-by: Masahiro Y

Kconfig: remove sym_set_choice_value

sym_set_choice_value could be removed and directly call
sym_set_tristate_value instead.

Signed-off-by: Zeng Heng <[email protected]>
Suggested-by: Masahiro Yamada <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

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kconfig: Add `make mod2noconfig` to disable module options

When converting a modular kernel to a monolithic kernel, once the kernel
works without loading any modules, this helps to quickly disable a

kconfig: Add `make mod2noconfig` to disable module options

When converting a modular kernel to a monolithic kernel, once the kernel
works without loading any modules, this helps to quickly disable all the
modules before turning off module support entirely.

Refactor conf_rewrite_mod_or_yes to a more general
conf_rewrite_tristates that accepts an old and new state.

Signed-off-by: Josh Triplett <[email protected]>
Tested-by: Björn Töpel <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

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kconfig: refactor listnewconfig code

We can reuse __print_symbol() helper to print symbols for listnewconfig.
Only the difference is the format for "n" symbols.

This prints "CONFIG_FOO=n" instead o

kconfig: refactor listnewconfig code

We can reuse __print_symbol() helper to print symbols for listnewconfig.
Only the difference is the format for "n" symbols.

This prints "CONFIG_FOO=n" instead of "# CONFIG_FOO is not set".

Signed-off-by: Masahiro Yamada <[email protected]>

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kconfig: remove 'const' from the return type of sym_escape_string_value()

sym_escape_string_value() returns a malloc'ed memory, but as
(const char *). So, it must be casted to (void *) when it is fr

kconfig: remove 'const' from the return type of sym_escape_string_value()

sym_escape_string_value() returns a malloc'ed memory, but as
(const char *). So, it must be casted to (void *) when it is free'd.
This is odd.

The return type of sym_escape_string_value() should be (char *).

I exploited that free(NULL) has no effect.

Signed-off-by: Masahiro Yamada <[email protected]>

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kconfig: constify long_opts

getopt_long() does not modify the long_opts structure.

Signed-off-by: Masahiro Yamada <[email protected]>

kconfig: remove allnoconfig_y option

Now that the only user, CONFIG_EMBEDDED has stopped using this option,
remove it entirely.

Signed-off-by: Masahiro Yamada <[email protected]>

kconfig: move conf_set_all_new_symbols() to conf.c

This function is only used in conf.c. Move it there together with the
randomize_choice_values() helper.

Define 'enum conf_def_mode' locally in con

kconfig: move conf_set_all_new_symbols() to conf.c

This function is only used in conf.c. Move it there together with the
randomize_choice_values() helper.

Define 'enum conf_def_mode' locally in conf.c as well.

Signed-off-by: Masahiro Yamada <[email protected]>

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kconfig: move conf_rewrite_mod_or_yes() to conf.c

This function is only used in conf.c.

Signed-off-by: Masahiro Yamada <[email protected]>

kconfig: remove assignment for Kconfig file

Pass av[optind] to conf_parse() directly.

Signed-off-by: Masahiro Yamada <[email protected]>

kconfig: add help messages for --help (-h) and --silent (-s)

Add missing options and make the help message more readable.

Signed-off-by: Masahiro Yamada <[email protected]>

kconfig: add long options --help and --silent

They are long options for -h and -s, respectively.

Signed-off-by: Masahiro Yamada <[email protected]>

kconfig: refactor option parse code

The current option parse code is clumsy.

The 's' option is separately handled in an if-conditional due to the
following code:

input_mode = (enum input_mode)

kconfig: refactor option parse code

The current option parse code is clumsy.

The 's' option is separately handled in an if-conditional due to the
following code:

input_mode = (enum input_mode)opt;

If 's' is moved to the switch statement, the invalid value 's' would
be assigned to the input_mode.

Another potential problem is that we are mixing 'enum input_mode' and
ASCII characters. They could overwrap if we add more input modes.

To separate them out, set the flag field of long options to a pointer
of input_mode_opt. For mode select options, getopt_long() returns 0,
which never causes overwrap with ASCII characters that represent short
options.

Signed-off-by: Masahiro Yamada <[email protected]>

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kconfig: split randconfig setup code into set_randconfig_seed()

This code is too big to be placed in the switch statement.

Move the code into a new helper function. I slightly refactor the code
wit

kconfig: split randconfig setup code into set_randconfig_seed()

This code is too big to be placed in the switch statement.

Move the code into a new helper function. I slightly refactor the code
without changing the behavior.

Signed-off-by: Masahiro Yamada <[email protected]>

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kconfig: omit --oldaskconfig option for 'make config'

scripts/kconfig/conf.c line 39 defines the default of input_mode as
oldaskconfig. Hence, 'make config' works in the same way even without
the --

kconfig: omit --oldaskconfig option for 'make config'

scripts/kconfig/conf.c line 39 defines the default of input_mode as
oldaskconfig. Hence, 'make config' works in the same way even without
the --oldaskconfig option given. Note this in the help message.

This will be helpful to unify build rules in Makefile in the next
commit.

Signed-off-by: Masahiro Yamada <[email protected]>

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