[PATCH] kconfig: forbid symbols that end with '_MODULE'
From: Masahiro Yamada <masahiroy@kernel.org>
Date: 2021-08-25 04:18:48
Also in:
alsa-devel, linux-kbuild, linux-wireless, lkml
Subsystem:
intel wireless wifi link (iwlwifi), kconfig, sound, sound - soc layer / dynamic audio power management (asoc), texas instruments asoc drivers, the rest · Maintainers:
Miri Korenblit, Nathan Chancellor, Nicolas Schier, Jaroslav Kysela, Takashi Iwai, Liam Girdwood, Mark Brown, Sen Wang, Linus Torvalds
Kconfig (syncconfig) generates include/generated/autoconf.h to make
CONFIG options available to the pre-processor.
The macros are suffixed with '_MODULE' for symbols with the value 'm'.
Here is a conflict; CONFIG_FOO=m results in '#define CONFIG_FOO_MODULE 1',
but CONFIG_FOO_MODULE=y also results in the same define.
fixdep always assumes CONFIG_FOO_MODULE comes from CONFIG_FOO=m, so the
dependency is not properly tracked for symbols that end with '_MODULE'.
This commit makes Kconfig error out if it finds a symbol suffixed with
'_MODULE'. This restriction does not exist if the module feature is not
supported (at least from the Kconfig perspective).
It detected one error:
error: SND_SOC_DM365_VOICE_CODEC_MODULE: symbol name must not end with '_MODULE'
Rename it to SND_SOC_DM365_VOICE_CODEC_MODULAR. Commit 147162f57515
("ASoC: ti: fix SND_SOC_DM365_VOICE_CODEC dependencies") added it for
internal use. So, this renaming has no impact on users.
Remove a comment from drivers/net/wireless/intel/iwlwifi/Kconfig since
this is a hard error now.
Add a comment to include/linux/kconfig.h in order not to worry observant
developers.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---
drivers/net/wireless/intel/iwlwifi/Kconfig | 1 -
include/linux/kconfig.h | 3 ++
scripts/kconfig/parser.y | 40 +++++++++++++++++++++-
sound/soc/ti/Kconfig | 2 +-
4 files changed, 43 insertions(+), 3 deletions(-)
diff --git a/drivers/net/wireless/intel/iwlwifi/Kconfig b/drivers/net/wireless/intel/iwlwifi/Kconfig
index 1085afbefba8..5b238243617c 100644
--- a/drivers/net/wireless/intel/iwlwifi/Kconfig
+++ b/drivers/net/wireless/intel/iwlwifi/Kconfig@@ -70,7 +70,6 @@ config IWLMVM of the devices that use this firmware is available here: https://wireless.wiki.kernel.org/en/users/drivers/iwlwifi#firmware -# don't call it _MODULE -- will confuse Kconfig/fixdep/... config IWLWIFI_OPMODE_MODULAR bool default y if IWLDVM=m
diff --git a/include/linux/kconfig.h b/include/linux/kconfig.h
index 20d1079e92b4..54f677e742fe 100644
--- a/include/linux/kconfig.h
+++ b/include/linux/kconfig.h@@ -53,6 +53,9 @@ * IS_MODULE(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'm', 0 * otherwise. CONFIG_FOO=m results in "#define CONFIG_FOO_MODULE 1" in * autoconf.h. + * CONFIG_FOO_MODULE=y would also result in "#define CONFIG_FOO_MODULE 1", + * but Kconfig forbids symbol names that end with '_MODULE', so that would + * not happen. */ #define IS_MODULE(option) __is_defined(option##_MODULE)
diff --git a/scripts/kconfig/parser.y b/scripts/kconfig/parser.y
index 2af7ce4e1531..b0f73f74ccd3 100644
--- a/scripts/kconfig/parser.y
+++ b/scripts/kconfig/parser.y@@ -475,6 +475,37 @@ assign_val: %% +/* + * Symbols suffixed with '_MODULE' would cause a macro conflict in autoconf.h, + * and also confuse the interaction between syncconfig and fixdep. + * Error out if a symbol with the '_MODULE' suffix is found. + */ +static int sym_check_name(struct symbol *sym) +{ + static const char *suffix = "_MODULE"; + static const size_t suffix_len = strlen("_MODULE"); + char *name; + size_t len; + + name = sym->name; + + if (!name) + return 0; + + len = strlen(name); + + if (len < suffix_len) + return 0; + + if (strcmp(name + len - suffix_len, suffix)) + return 0; + + fprintf(stderr, "error: %s: symbol name must not end with '%s'\n", + name, suffix); + + return -1; +} + void conf_parse(const char *name) { struct symbol *sym;
@@ -493,8 +524,15 @@ void conf_parse(const char *name) if (yynerrs) exit(1); - if (!modules_sym) + + if (modules_sym) { + for_all_symbols(i, sym) { + if (sym_check_name(sym)) + yynerrs++; + } + } else { modules_sym = sym_find( "n" ); + } if (!menu_has_prompt(&rootmenu)) { current_entry = &rootmenu;
diff --git a/sound/soc/ti/Kconfig b/sound/soc/ti/Kconfig
index 698d7bc84dcf..c56a5789056f 100644
--- a/sound/soc/ti/Kconfig
+++ b/sound/soc/ti/Kconfig@@ -211,7 +211,7 @@ config SND_SOC_DM365_VOICE_CODEC Say Y if you want to add support for SoC On-chip voice codec endchoice -config SND_SOC_DM365_VOICE_CODEC_MODULE +config SND_SOC_DM365_VOICE_CODEC_MODULAR def_tristate y depends on SND_SOC_DM365_VOICE_CODEC && SND_SOC select MFD_DAVINCI_VOICECODEC
--
2.30.2