Re: section breakage on ppc64 (aka __devinitconst is broken by design)

[Chuck Ebbert <cebbert@redhat.com>]

On 02/03/2008 08:08 AM, Al Viro wrote:
>
> The reason why it didn't visibly bite us before is that usually __devinit...
> just expanded to nothing (unless you disable HOTPLUG, which requires
> EMBEDDED, which wasn't apparently common enough for ppc64 builds).
>
> Suggestions?

This ugly hackset was needed to get 2.6.24 to build with GCC 4.3. It would
be nice to get a real fix...


--- a/include/linux/moduleparam.h
+++ b/include/linux/moduleparam.h
@@ -62,6 +62,15 @@ struct kparam_array
 	void *elem;
 };

+/* On some platforms relocations to global data cannot go into read-only
+   sections, so 'const' makes no sense and even causes compile failures
+   with some compilers. */
+#if defined(CONFIG_ALPHA) || defined(CONFIG_IA64) || defined(CONFIG_PPC64)
+#define __moduleparam_const
+#else
+#define __moduleparam_const const
+#endif
+
 /* This is the fundamental function for registering boot/module
    parameters.  perm sets the visibility in sysfs: 000 means it's
    not there, read bits mean it's readable, write bits mean it's
@@ -71,7 +80,7 @@ struct kparam_array
 	static int __param_perm_check_##name __attribute__((unused)) =	\
 	BUILD_BUG_ON_ZERO((perm) < 0 || (perm) > 0777 || ((perm) & 2));	\
 	static const char __param_str_##name[] = prefix #name;		\
-	static struct kernel_param const __param_##name			\
+	static struct kernel_param __moduleparam_const __param_##name	\
 	__attribute_used__						\
     __attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \
 	= { __param_str_##name, perm, set, get, { arg } }
--- linux-2.6.24.noarch.orig/include/linux/module.h
+++ linux-2.6.24.noarch/include/linux/module.h
@@ -30,6 +30,15 @@

 #define MODULE_NAME_LEN (64 - sizeof(unsigned long))

+/* On some platforms relocations to global data cannot go into read-only
+   sections, so 'const' makes no sense and even causes compile failures
+   with some compilers. */
+#if defined(CONFIG_ALPHA) || defined(CONFIG_IA64) || defined(CONFIG_PPC64)
+#define __ksym_const
+#else
+#define __ksym_const const
+#endif
+
 struct kernel_symbol
 {
 	unsigned long value;
@@ -192,7 +201,7 @@ void *__symbol_get_gpl(const char *symbo
 	static const char __kstrtab_##sym[]			\
 	__attribute__((section("__ksymtab_strings")))		\
 	= MODULE_SYMBOL_PREFIX #sym;                    	\
-	static const struct kernel_symbol __ksymtab_##sym	\
+	static __ksym_const struct kernel_symbol __ksymtab_##sym	\
 	__attribute_used__					\
 	__attribute__((section("__ksymtab" sec), unused))	\
 	= { (unsigned long)&sym, __kstrtab_##sym }