kbuild: set correct KBUILD_MODNAME when using well known kernel symbols as module names
This patch fixes a problem when we use well known kernel symbols as module
names.
For example, if module source name is current.c, idle_stack.c or etc.,
we have a bad KBUILD_MODNAME value.
For example, KBUILD_MODNAME will be "get_current()" instead of "current", or
"(init_thread_union.stack)" instead of "idle_task".
The trick is to define a stringify macro on the commandline - named
KBUILD_STR for namespace reasons - and then to stringify the module
name.
There are a few uses of KBUILD_MODNAME throughout the tree but the usage
is for debug and will not be harmed by this change so left untouched for now.
While at it KBUILD_BASENAME was changed too. Any spinlock usage in the
unix module would have created wrong section names without it.
Usage in spinlock.h fixed so it no longer stringify KBUILD_BASENAME.
Original patch from Ustyogov Roman - all bugs introduced by me.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
index 0e9682c..799be67 100644
--- a/include/linux/spinlock.h
+++ b/include/linux/spinlock.h
@@ -59,8 +59,7 @@
/*
* Must define these before including other files, inline functions need them
*/
-#define LOCK_SECTION_NAME \
- ".text.lock." __stringify(KBUILD_BASENAME)
+#define LOCK_SECTION_NAME ".text.lock."KBUILD_BASENAME
#define LOCK_SECTION_START(extra) \
".subsection 1\n\t" \
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 0f81dcf..550798f 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -81,8 +81,10 @@
# Note: It's possible that one object gets potentially linked into more
# than one module. In that case KBUILD_MODNAME will be set to foo_bar,
# where foo and bar are the name of the modules.
-basename_flags = -DKBUILD_BASENAME=$(subst $(comma),_,$(subst -,_,$(*F)))
-modname_flags = $(if $(filter 1,$(words $(modname))),-DKBUILD_MODNAME=$(subst $(comma),_,$(subst -,_,$(modname))))
+name-fix = $(subst $(comma),_,$(subst -,_,$1))
+basename_flags = -D"KBUILD_BASENAME=KBUILD_STR($(call name-fix,$(*F)))"
+modname_flags = $(if $(filter 1,$(words $(modname))),\
+ -D"KBUILD_MODNAME=KBUILD_STR($(call name-fix,$(modname)))")
_c_flags = $(CFLAGS) $(EXTRA_CFLAGS) $(CFLAGS_$(*F).o)
_a_flags = $(AFLAGS) $(EXTRA_AFLAGS) $(AFLAGS_$(*F).o)
@@ -113,7 +115,7 @@
c_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(CPPFLAGS) \
$(__c_flags) $(modkern_cflags) \
- $(basename_flags) $(modname_flags)
+ -D"KBUILD_STR(s)=\#s" $(basename_flags) $(modname_flags)
a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(CPPFLAGS) \
$(__a_flags) $(modkern_aflags)
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 8ce5a63..f70ff13 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -539,10 +539,9 @@
buf_printf(b, "\n");
buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
buf_printf(b, "\n");
- buf_printf(b, "#undef unix\n"); /* We have a module called "unix" */
buf_printf(b, "struct module __this_module\n");
buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n");
- buf_printf(b, " .name = __stringify(KBUILD_MODNAME),\n");
+ buf_printf(b, " .name = KBUILD_MODNAME,\n");
if (mod->has_init)
buf_printf(b, " .init = init_module,\n");
if (mod->has_cleanup)