Since commit f79dc03fe6 ("kconfig: refactor choice value
calculation"), when EXPERT is disabled, nothing within the "if INPUT"
... "endif" block in drivers/input/Kconfig is displayed. This issue
affects all command-line interfaces and GUI frontends.
The prompt for INPUT is hidden when EXPERT is disabled. Previously,
menu_is_visible() returned true in this case; however, it now returns
false, resulting in all sub-menu entries being skipped.
Here is a simplified test case illustrating the issue:
config A
bool "A" if X
default y
config B
bool "B"
depends on A
When X is disabled, A becomes unconfigurable and is forced to y.
B should be displayed, as its dependency is met.
This commit restores the necessary code, so menu_is_visible() functions
as it did previously.
Fixes: f79dc03fe6 ("kconfig: refactor choice value calculation")
Reported-by: Edmund Raile <edmund.raile@proton.me>
Closes: https://lore.kernel.org/all/5fd0dfc7ff171aa74352e638c276069a5f2e888d.camel@proton.me/
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Currently, every expression in Kconfig files produces a new abstract
syntax tree (AST), even if it is identical to a previously encountered
one.
Consider the following code:
config FOO
bool "FOO"
depends on (A || B) && C
config BAR
bool "BAR"
depends on (A || B) && C
config BAZ
bool "BAZ"
depends on A || B
The "depends on" lines are similar, but currently a separate AST is
allocated for each one.
The current data structure looks like this:
FOO->dep ==> AND BAR->dep ==> AND BAZ->dep ==> OR
/ \ / \ / \
OR C OR C A B
/ \ / \
A B A B
This is redundant; FOO->dep and BAR->dep have identical ASTs but
different memory instances.
We can optimize this; FOO->dep and BAR->dep can share the same AST, and
BAZ->dep can reference its sub tree.
The optimized data structure looks like this:
FOO->dep, BAR->dep ==> AND
/ \
BAZ->dep ==> OR C
/ \
A B
This commit introduces a hash table to keep track of allocated
expressions. If an identical expression is found, it is reused.
This does not necessarily result in memory savings, as menu_finalize()
transforms expressions without freeing up stale ones. This will be
addressed later.
One optimization that can be easily implemented is caching the
expression's value. Once FOO's dependency, (A || B) && C, is calculated,
it can be cached, eliminating the need to recalculate it for BAR.
This commit also reverts commit e983b7b17a ("kconfig/menu.c: fix
multiple references to expressions in menu_add_prop()").
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
I believe its last usage was in the following code:
if (prop == NULL)
prop = stack->sym->prop;
This code was previously used to print the file name and line number of
associated symbols in sym_check_print_recursive(), which was removed by
commit 9d0d266046 ("kconfig: recursive checks drop file/lineno").
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Move array_size.h, hashtable.h, list.h, list_types.h from scripts/kconfig/
to scripts/include/.
These headers will be useful for other host programs.
Remove scripts/mod/list.h.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
When a prompt is followed by "if <expr>", the symbol is configurable
when the if-conditional evaluates to true.
A typical usage is as follows:
menuconfig BLOCK
bool "Enable the block layer" if EXPERT
default y
When EXPERT=n, the prompt is hidden, but this config entry is still
active, and BLOCK is set to its default value 'y'. When EXPERT=y, the
prompt is shown, making BLOCK a user-configurable option.
This usage is common throughout the kernel tree, but it has never worked
within a choice block.
[Test Code]
config EXPERT
bool "Allow expert users to modify more options"
choice
prompt "Choose" if EXPERT
config A
bool "A"
config B
bool "B"
endchoice
[Result]
# CONFIG_EXPERT is not set
When the prompt is hidden, the choice block should produce the default
without asking for the user's preference. Hence, the output should be:
# CONFIG_EXPERT is not set
CONFIG_A=y
# CONFIG_B is not set
Removing unnecessary hacks fixes the issue.
This commit also changes the behavior of 'select' by choice members.
[Test Code 2]
config MODULES
def_bool y
modules
config DEP
def_tristate m
if DEP
choice
prompt "choose"
config A
bool "A"
select C
endchoice
config B
def_bool y
select D
endif
config C
tristate
config D
tristate
The current output is as follows:
CONFIG_MODULES=y
CONFIG_DEP=m
CONFIG_A=y
CONFIG_B=y
CONFIG_C=y
CONFIG_D=m
With this commit, the output will be changed as follows:
CONFIG_MODULES=y
CONFIG_DEP=m
CONFIG_A=y
CONFIG_B=y
CONFIG_C=m
CONFIG_D=m
CONFIG_C will be changed to 'm' because 'select C' will inherit the
dependency on DEP, which is 'm'.
This change is aligned with the behavior of 'select' outside a choice
block; 'select D' depends on DEP, therefore D is selected by (B && DEP).
Note:
With this commit, allmodconfig will set CONFIG_USB_ROLE_SWITCH to 'm'
instead of 'y'. I did not see any build regression with this change.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
P_CHOICE is a pseudo property used to link a choice with its members.
There is no more code relying on this, except for some debug code.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Handling choices has always been in a PITA in Kconfig.
For example, fixes and reverts were repeated for randconfig with
KCONFIG_ALLCONFIG:
- 422c809f03 ("kconfig: fix randomising choice entries in presence of KCONFIG_ALLCONFIG")
- 23a5dfdad2 ("Revert "kconfig: fix randomising choice entries in presence of KCONFIG_ALLCONFIG"")
- 8357b48549 ("kconfig: fix randomising choice entries in presence of KCONFIG_ALLCONFIG")
- 490f161711 ("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 <masahiroy@kernel.org>
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:
- df8df5e4bc ("usb: get rid of 'choice' for legacy gadget drivers")
- bfb57ef054 ("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 fa64e5f6a3 ("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/20240427104231.2728905-1-masahiroy@kernel.org/T/#m0a1bb6992581462ceca861b409bb33cb8fd7dbae
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
expr_trans_bool() performs an incorrect transformation.
[Test Code]
config MODULES
def_bool y
modules
config A
def_bool y
select C if B != n
config B
def_tristate m
config C
tristate
[Result]
CONFIG_MODULES=y
CONFIG_A=y
CONFIG_B=m
CONFIG_C=m
This output is incorrect because CONFIG_C=y is expected.
Documentation/kbuild/kconfig-language.rst clearly explains the function
of the '!=' operator:
If the values of both symbols are equal, it returns 'n',
otherwise 'y'.
Therefore, the statement:
select C if B != n
should be equivalent to:
select C if y
Or, more simply:
select C
Hence, the symbol C should be selected by the value of A, which is 'y'.
However, expr_trans_bool() wrongly transforms it to:
select C if B
Therefore, the symbol C is selected by (A && B), which is 'm'.
The comment block of expr_trans_bool() correctly explains its intention:
* bool FOO!=n => FOO
^^^^
If FOO is bool, FOO!=n can be simplified into FOO. This is correct.
However, the actual code performs this transformation when FOO is
tristate:
if (e->left.sym->type == S_TRISTATE) {
^^^^^^^^^^
While it can be fixed to S_BOOLEAN, there is no point in doing so
because expr_tranform() already transforms FOO!=n to FOO when FOO is
bool. (see the "case E_UNEQUAL" part)
expr_trans_bool() is wrong and unnecessary.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Choices and their members are associated via the P_CHOICE property.
Currently, prop_get_symbol(sym_get_choice_prop()) is used to obtain
the choice of the given choice member.
Replace it with sym_get_choice_menu(), which retrieves the choice
without relying on P_CHOICE.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
menu_finalize() warns default properties for choice members and prompts
outside the choice block. These should be hard errors.
While I was here, I moved the checks to slim down menu_finalize().
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Choice members must have a prompt; hence make it an error.
While I was here, I moved the check to the parser to slim down
_menu_finalize().
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The 'choice' statement is primarily used to exclusively select one
option, but the 'optional' property allows all entries to be disabled.
In the following example, both A and B can be disabled simultaneously:
choice
prompt "choose A, B, or nothing"
optional
config A
bool "A"
config B
bool "B"
endchoice
You can achieve the equivalent outcome by other means.
A common solution is to add another option to guard the choice block.
In the following example, you can set ENABLE_A_B_CHOICE=n to disable
the entire choice block:
choice
prompt "choose A or B"
depends on ENABLE_A_B_CHOICE
config A
bool "A"
config B
bool "B"
endchoice
Another approach is to insert one more entry:
choice
prompt "choose A, B, or disable both"
config A
bool "A"
config B
bool "B"
config DISABLE_A_AND_B
bool "choose this to disable both A and B"
endchoice
Some real examples are DEBUG_INFO_NONE, INITRAMFS_COMPRESSION_NONE,
LTO_NONE, etc.
The 'optional' property is even more unnecessary for a tristate choice.
Without the 'optional' property, you can disable A and B; you can set
'm' in the choice prompt, and disable A and B individually:
choice
prompt "choose one built-in or make them modular"
config A
tristate "A"
config B
tristate "B"
endchoice
In conclusion, the 'optional' property was unneeded.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
Several functions require traversing menu entries sequentially. This
commit introduces some helpers to simplify such operations.
The menu_next() function facilitates depth-first traversal:
1. Descend to the child level if the current menu has one
2. Move to the next sibling at the same level if available
3. Ascend to the parent level if there is no more child or sibling
The menu_for_each_sub_entry() macro iterates over all submenu entries
using depth-first traverse.
The menu_for_each_entry() macro is the same, but over all menu entries.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
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 <masahiroy@kernel.org>
Currently, get_symbol_str() uses a tricky approach to traverse the
associated menus.
With relevant menus now linked to the symbol using a linked list,
use list_for_each_entry() for iterating on the menus.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Currently, there is no direct link from (struct symbol) to (struct menu).
It is still possible to access associated menus through the P_SYMBOL
property, because property::menu is the relevant menu entry, but it
results in complex code, as seen in get_symbol_str().
Use a linked list for simpler traversal of relevant menus.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Do not feed back the choice type to choice values.
Each choice value should explicitly specify 'bool' or 'tristate',
as all the Kconfig files already do. If the type were missing,
"config symbol defined without type" would be shown.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The struct list_head is often embedded in other structures, while other
code is used in C functions.
By separating struct list_head into its own header, other headers are no
longer required to include the entire list.h.
This is similar to the kernel space, where struct list_head is defined
in <linux/types.h> instead of <linux/list.h>.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Currently, file_lookup() returns a pointer to (struct file), but the
callers use only file->name.
Make it return the ->name member directly.
This adjustment encapsulates struct file and file_list as internal
implementation.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
struct file has two link nodes, 'next' and 'parent'.
The former is used to link files in the 'file_list' linked list,
which manages the list of Kconfig files seen so far.
The latter is used to link files in the 'current_file' linked list,
which manages the inclusion ("source") tree.
The latter should be tracked together with the lexer state.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
struct property is linked to struct file for diagnostic purposes.
It is always used to retrieve the file name through prop->file->name.
Associate struct property with the file name directly.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
struct menu is linked to struct file for diagnostic purposes.
It is always used to retrieve the file name through menu->file->name.
Associate struct menu with the file name directly.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Now zconf_curname() and zconf_lineno() are so simple that they just
return cur_filename, cur_lineno, respectively.
Remove these functions, and then use cur_filename and cur_lineno
directly.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
menu_has_help() and menu_get_help() functions are only used within
menu_get_ext_help().
Squash them into menu_get_ext_help(). It revealed the if-conditional
in menu_get_help() was unneeded, as menu_has_help() has already checked
that menu->help is not NULL.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
You do not need to remember the index of each jump key because you can
count it up after a key is pressed.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Jesse Taube <Mr.Bossman075@gmail.com>
Commit 95ac9b3b58 ("menuconfig: Assign jump keys per-page instead
of globally") injected a lot of hacks to the bottom of the textbox
infrastructure.
I reverted many of them without changing the behavior. (almost)
Now, the key markers are inserted when constructing the search result
instead of updating the text buffer on-the-fly.
The buffer passed to the textbox got back to a constant string.
The ugly casts from (const char *) to (char *) went away.
A disadvantage is that the same key numbers might be displayed multiple
times in the dialog if you use a huge window (but I believe it is
unlikely to happen).
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Jesse Taube <Mr.Bossman075@gmail.com>
Since commit d05377e184 ("kconfig: Create links to main menu items
in search"), menuconfig shows a jump key next to "Main menu" if the
nearest visible parent is the rootmenu. If you press that jump key,
menuconfig crashes with a segmentation fault.
For example, do this:
$ make ARCH=arm64 allnoconfig menuconfig
Press '/' to search for the string "ACPI". Press '1' to choose
"(1) Main menu". Then, menuconfig crashed with a segmentation fault.
The following code in search_conf()
conf(targets[i]->parent, targets[i]);
results in NULL pointer dereference because targets[i] is the rootmenu,
which does not have a parent.
Commit d05377e184 tried to fix the issue of top-level items not having
a jump key, but adding the "Main menu" was not the right fix.
The correct fix is to show the searched item itself. This fixes another
weird behavior described in the comment block.
Fixes: d05377e184 ("kconfig: Create links to main menu items in search")
Reported-by: Johannes Zink <j.zink@pengutronix.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
Tested-by: Johannes Zink <j.zink@pengutronix.de>
There is nowhere calling `menu_get_root_menu` function,
so remove it.
Signed-off-by: Zeng Heng <zengheng4@huawei.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
When one searches for a main menu item, links aren't created for it like
with the rest of the symbols.
This happens because we trace the item until we get to the rootmenu, but
we don't include it in the path of the item. The rationale was probably
that we don't want to show the main menu in the path of all items,
because it is redundant.
However, when an item has only the rootmenu in its path it should be
included, because this way the user can jump to its location.
Add a 'Main menu' entry in the 'Location:' section for the kconfig
items.
This makes the 'if (i > 0)' superfluous because each item with prompt
will have at least one menu in its path.
Signed-off-by: Ariel Marcovitch <arielmarcovitch@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Now "modules" is the only member of the "option" property.
Remove "option", and move "modules" to the top level property.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
"defconfig_list" is a weird option that defines a static symbol that
declares the list of base config files in case the .config does not
exist yet.
This is quite different from other normal symbols; we just abused the
"string" type and the "default" properties to list out the input files.
They must be fixed values since these are searched for and loaded in
the parse stage.
It is an ugly hack, and should not exist in the first place. Providing
this feature as an environment variable is a saner approach.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
When we generate the help text of a symbol (e.g. when a user presses '?'
in menuconfig), we do two things:
1. We iterate through every prompt that belongs to that symbol,
printing its text and its location in the menu tree.
2. We print symbol-wide information that's not linked to a particular
prompt, such as what it selects/is selected by and what it
implies/is implied by.
Each prompt we print for 1 starts with a line that's not indented
indicating where the prompt is defined, then continues with indented
lines that describe properties of that particular definition.
Once we get to 2, however, we print all the global data indented as
well! Visually, this makes it look like the symbol-wide data is
associated with the last prompt we happened to print rather than
the symbol as a whole.
Fix this by removing the indentation for symbol-wide information.
Before:
Symbol: CPU_FREQ [=n]
Type : bool
Defined at drivers/cpufreq/Kconfig:4
Prompt: CPU Frequency scaling
Location:
-> CPU Power Management
-> CPU Frequency scaling
Selects: SRCU [=n]
Selected by [n]:
- ARCH_SA1100 [=n] && <choice>
After:
Symbol: CPU_FREQ [=n]
Type : bool
Defined at drivers/cpufreq/Kconfig:4
Prompt: CPU Frequency scaling
Location:
-> CPU Power Management
-> CPU Frequency scaling
Selects: SRCU [=n]
Selected by [n]:
- ARCH_SA1100 [=n] && <choice>
Signed-off-by: Thomas Hebb <tommyhebb@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Kconfig makes a distinction between dependencies (defined by "depends
on" expressions and enclosing "if" blocks) and visibility (which
includes all dependencies, but also includes inline "if" expressions of
individual properties as well as, for prompts, "visible if" expressions
of enclosing menus).
Before commit bcdedcc1af ("menuconfig: print more info for symbol
without prompts"), the "Depends on" lines of a symbol's help text
indicated the visibility of the prompt property they appeared under.
After bcdedcc1af, there was always only a single "Depends on" line,
which indicated the visibility of the first P_SYMBOL property of the
symbol. Since P_SYMBOLs never have inline if expressions, this was in
effect the same as the dependencies of the menu item that the P_SYMBOL
was attached to.
Neither of these situations accurately conveyed the dependencies of a
symbol--the first because it was actually the visibility, and the second
because it only showed the dependencies from a single definition.
With this series, we are back to printing separate dependencies for each
definition, but we print the actual dependencies (rather than the
visibility) in the "Depends on" line. However, it can still be useful to
know the visibility of a prompt, so this patch adds a "Visible if" line
that shows the visibility only if the visibility is different from the
dependencies (which it isn't for most prompts in Linux).
Before:
Symbol: THUMB2_KERNEL [=n]
Type : bool
Defined at arch/arm/Kconfig:1417
Prompt: Compile the kernel in Thumb-2 mode
Depends on: (CPU_V7 [=y] || CPU_V7M [=n]) && !CPU_V6 [=n] && !CPU_V6K [=n]
Location:
-> Kernel Features
Selects: ARM_UNWIND [=n]
After:
Symbol: THUMB2_KERNEL [=n]
Type : bool
Defined at arch/arm/Kconfig:1417
Prompt: Compile the kernel in Thumb-2 mode
Depends on: (CPU_V7 [=y] || CPU_V7M [=n]) && !CPU_V6 [=n] && !CPU_V6K [=n]
Visible if: (CPU_V7 [=y] || CPU_V7M [=n]) && !CPU_V6 [=n] && !CPU_V6K [=n] && !CPU_THUMBONLY [=n]
Location:
-> Kernel Features
Selects: ARM_UNWIND [=n]
Signed-off-by: Thomas Hebb <tommyhebb@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
In Kconfig, each symbol (representing a config option) can be defined in
multiple places. Each definition may or may not have a prompt, which
allows the option to be set via an interface like menuconfig. Each
definition has a set of dependencies, which determine whether its prompt
is visible and whether other pieces of the definition, like a default
value, take effect.
Historically, a symbol's help text (i.e. what's shown when a user
presses '?' in menuconfig) contained some symbol-wide information not
tied to any particular definition (e.g. what other symbols it selects)
as well as the location (file name and line number) and dependencies of
each prompt. Notably, the help text did not show the location or
dependencies of definitions without prompts.
Because this made it hard to reason about symbols that had no prompts,
commit bcdedcc1af ("menuconfig: print more info for symbol without
prompts") changed the help text so that, instead of containing the
location and dependencies of each prompt, it contained the location and
dependencies of the symbol's first definition, regardless of whether or
not that definition had a prompt.
For symbols with only one definition, that change makes sense. However,
it breaks down for symbols with multiple definitions: each definition
has its own set of dependencies (the `dep` field of `struct menu`), and
those dependencies are ORed together to get the symbol's dependency list
(the `dir_dep` field of `struct symbol`). By printing only the
dependencies of the first definition, the help text misleads users into
believing that an option is more narrowly-applicable than it actually
is.
For an extreme example of this, we can look at the SYS_TEXT_BASE symbol
in the Das U-Boot project (version 2019.10), which also uses Kconfig. (I
unfortunately could not find an illustrative example in Linux.) This
config option specifies the load address of the built binary and, as
such, is applicable to basically every configuration possible. And yet,
without this patch, its help text is as follows:
Symbol: SYS_TEXT_BASE [=]
Type : hex
Prompt: U-Boot base address
Location:
-> ARM architecture
Prompt: Text Base
Location:
-> Boot images
Defined at arch/arm/mach-aspeed/Kconfig:9
Depends on: ARM [=n] && ARCH_ASPEED [=n]
The help text indicates that the option is applicable only for a
specific unselected architecture (aspeed), because that architecture's
promptless definition (which just sets a default value), happens to be
the first one seen. No definition or dependency information is printed
for either of the two prompts listed.
Because source locations and dependencies are fundamentally properties
of definitions and not of symbols, we should treat them as such. This
patch brings back the pre-bcdedcc1afd6 behavior for definitions with
prompts but also separately prints the location and dependencies of
those without prompts, solving the original problem in a different way.
With this change, our SYS_TEXT_BASE example becomes
Symbol: SYS_TEXT_BASE [=]
Type : hex
Defined at arch/arm/mach-stm32mp/Kconfig:83
Prompt: U-Boot base address
Depends on: ARM [=n] && ARCH_STM32MP [=n]
Location:
-> ARM architecture
Defined at Kconfig:532
Prompt: Text Base
Depends on: !NIOS2 [=n] && !XTENSA [=n] && !EFI_APP [=n]
Location:
-> Boot images
Defined at arch/arm/mach-aspeed/Kconfig:9
Depends on: ARM [=n] && ARCH_ASPEED [=n]
Defined at arch/arm/mach-socfpga/Kconfig:25
Depends on: ARM [=n] && ARCH_SOCFPGA [=n]
<snip>
Defined at board/sifive/fu540/Kconfig:15
Depends on: RISCV [=n] && TARGET_SIFIVE_FU540 [=n]
which is a much more accurate representation.
Note that there is one notable difference between what gets printed for
prompts after this change and what got printed before bcdedcc1af: the
"Depends on" line now accurately represents the prompt's dependencies
instead of conflating those with the prompt's visibility (which can
include extra conditions). See the patch later in this series titled
"kconfig: distinguish between dependencies and visibility in help text"
for more details and better handling of that nuance.
Signed-off-by: Thomas Hebb <tommyhebb@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
menu_add_prompt() is the only function that calls menu_add_prop() with
non-NULL prompt.
So, the code inside the if-conditional block of menu_add_prop() can be
moved to menu_add_prompt().
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
In menu_finalize(), the dependency of a menu entry is propagated
downwards.
For the 'menu', parent->dep and parent->prompt->visible.expr have
the same expression. Both accumulate the 'depends on' of itself and
upper menu entries.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This reverts commit ba6ff60d5e ("kconfig: don't emit warning upon
rootmenu's prompt redefinition").
At that time, rootmenu.prompt was always set first, then it was set
again if a "mainmenu" statement was specified in the Kconfig file.
This is no longer the case since commit 0724a7c32a ("kconfig: Don't
leak main menus during parsing"). Remove the unneeded check.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
All files in lxdialog/ are licensed under GPL-2.0+, and the rest are
under GPL-2.0. I added GPL-2.0 tags to test scripts in tests/.
Documentation/process/license-rules.rst does not suggest anything
about the flex/bison files. Because flex does not accept the C++
comment style at the very top of a file, I used the C style for
zconf.l, and so for zconf.y for consistency.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
For the keywords "modules", "defconfig_list", and "allnoconfig_y",
the lexer should pass specific tokens instead of generic T_WORD.
This simplifies both the lexer and the parser.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
