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 <[email protected]>
---
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
Masahiro Yamada <[email protected]> writes:
> 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'.
It seem to me the problem is in autoconf.h/fixdep, not in the Kconfig
language.
> This commit makes Kconfig error out if it finds a symbol suffixed with
> '_MODULE'.
I know you don't care, but I will voice my objection, for the record:
Kconfig is used by projects other than the Linux kernel and some of
them do not use the autoconf.h functionality. For such projects this
restriction seems arbitrary and potentially backwards-incompatible.