kernel/linux.git/scripts/kconfig/parser.y, branch v6.19.11

kconfig: Add transitional symbol attribute for migration support

2025-09-24T21:23:35+00:00

During kernel option migrations (e.g. CONFIG_CFI_CLANG to CONFIG_CFI), existing .config files need to maintain backward compatibility while preventing deprecated options from appearing in newly generated configurations. This is challenging with existing Kconfig mechanisms because: 1. Simply removing old options breaks existing .config files. 2. Manually listing an option as "deprecated" leaves it needlessly visible and still writes them to new .config files. 3. Using any method to remove visibility (.e.g no 'prompt', 'if n', etc) prevents the option from being processed at all. Add a "transitional" attribute that creates symbols which are: - Processed during configuration (can influence other symbols' defaults) - Hidden from user menus (no prompts appear) - Omitted from newly written .config files (gets migrated) - Restricted to only having help sections (no defaults, selects, etc) making it truly just a "prior value pass-through" option. The transitional syntax requires a type argument and prevents type redefinition: config NEW_OPTION bool "New option" default OLD_OPTION config OLD_OPTION bool transitional help Transitional config for OLD_OPTION migration. This allows seamless migration: olddefconfig processes existing CONFIG_OLD_OPTION=y settings to enable CONFIG_NEW_OPTION=y, while CONFIG_OLD_OPTION is omitted from newly generated .config files. Added positive and negative testing via "testconfig" make target. Co-developed-by: Vegard Nossum Signed-off-by: Vegard Nossum Reviewed-by: Nathan Chancellor Tested-by: Nathan Chancellor Link: https://lore.kernel.org/r/20250923213422.1105654-2-kees@kernel.org Signed-off-by: Kees Cook

kconfig: introduce menu type enum

2025-06-05T20:40:25+00:00

Currently, menu->prompt->type is checked to distinguish "comment" (P_COMMENT) and "menu" (P_MENU) entries from regular "config" entries. This is odd because P_COMMENT and P_MENU are not properties. This commit introduces menu type enum to distinguish menu types more naturally. Signed-off-by: Masahiro Yamada

kconfig: remove zconfprint()

2024-11-04T08:53:09+00:00

Turn all warnings during parsing into hard errors. Signed-off-by: Masahiro Yamada

kconfig: remove support for "bool" prompt for choice entries

2024-11-04T08:53:09+00:00

Since commit fde192511bdb ("kconfig: remove tristate choice support"), all choice blocks are now boolean. There is no longer a need to specify the choice type explicitly. All "bool" prompts in choice entries have been converted to "prompt". This commit removes support for the "bool" syntax in choice entries. Signed-off-by: Masahiro Yamada

kconfig: fix infinite loop in sym_calc_choice()

2024-09-30T11:42:52+00:00

Since commit f79dc03fe68c ("kconfig: refactor choice value calculation"), Kconfig for ARCH=powerpc may result in an infinite loop. This occurs because there are two entries for POWERPC64_CPU in a choice block. If the same symbol appears twice in a choice block, the ->choice_link node is added twice to ->choice_members, resulting a corrupted linked list. A simple test case is: choice prompt "choice" config A bool "A" config B bool "B 1" config B bool "B 2" endchoice Running 'make defconfig' results in an infinite loop. One solution is to replace the current two entries: config POWERPC64_CPU bool "Generic (POWER5 and PowerPC 970 and above)" depends on PPC_BOOK3S_64 && !CPU_LITTLE_ENDIAN select PPC_64S_HASH_MMU config POWERPC64_CPU bool "Generic (POWER8 and above)" depends on PPC_BOOK3S_64 && CPU_LITTLE_ENDIAN select ARCH_HAS_FAST_MULTIPLIER select PPC_64S_HASH_MMU select PPC_HAS_LBARX_LHARX with the following single entry: config POWERPC64_CPU bool "Generic 64 bit powerpc" depends on PPC_BOOK3S_64 select ARCH_HAS_FAST_MULTIPLIER if CPU_LITTLE_ENDIAN select PPC_64S_HASH_MMU select PPC_HAS_LBARX_LHARX if CPU_LITTLE_ENDIAN In my opinion, the latter looks cleaner, but PowerPC maintainers may prefer to display different prompts depending on CPU_LITTLE_ENDIAN. For now, this commit fixes the issue in Kconfig, restoring the original behavior. I will reconsider whether such a use case is worth supporting. Fixes: f79dc03fe68c ("kconfig: refactor choice value calculation") Reported-by: Marco Bonelli Closes: https://lore.kernel.org/all/1763151587.3581913.1727224126288@privateemail.com/ Signed-off-by: Masahiro Yamada

kbuild: split x*alloc() functions in kconfig to scripts/include/xalloc.h

2024-09-01T11:34:48+00:00

These functions will be useful for other host programs. Signed-off-by: Masahiro Yamada

kconfig: remove P_SYMBOL property

2024-09-01T11:34:48+00:00

P_SYMBOL is a pseudo property that was previously used for data linking purposes. It is no longer used except for debug prints. Remove it. Signed-off-by: Masahiro Yamada

kconfig: remove dummy assignments to cur_{filename,lineno}

2024-09-01T11:34:47+00:00

Since commit ca4c74ba306e ("kconfig: remove P_CHOICE property"), menu_finalize() no longer calls menu_add_symbol(). No function references cur_filename or cur_lineno after yyparse(). Signed-off-by: Masahiro Yamada

kconfig: add const qualifiers to several function arguments

2024-07-16T07:07:14+00:00

Clarify that the given structures are not modified. Signed-off-by: Masahiro Yamada

kconfig: remove P_CHOICE property

2024-07-15T16:08:37+00:00

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