module: fix and elaborate comments

Fix and elaborate comments.
Signed-off-by: Matti Linnanvuori <mattilinnanvuori@yahoo.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

kernel/module.c

@@ -81,7 +81,8 @@ int unregister_module_notifier(struct notifier_block * nb)
 }
 EXPORT_SYMBOL(unregister_module_notifier);
 
-/* We require a truly strong try_module_get() */
+/* We require a truly strong try_module_get(): 0 means failure due to
+   ongoing or failed initialization etc. */
 static inline int strong_try_module_get(struct module *mod)
 {
 	if (mod && mod->state == MODULE_STATE_COMING)
@@ -952,7 +953,8 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
 	ret = __find_symbol(name, &owner, &crc,
 			!(mod->taints & TAINT_PROPRIETARY_MODULE));
 	if (ret) {
-		/* use_module can fail due to OOM, or module unloading */
+		/* use_module can fail due to OOM,
+		   or module initialization or unloading */
 		if (!check_version(sechdrs, versindex, name, mod, crc) ||
 		    !use_module(mod, owner))
 			ret = 0;
@@ -1369,7 +1371,7 @@ dup:
 	return ret;
 }
 
-/* Change all symbols so that sh_value encodes the pointer directly. */
+/* Change all symbols so that st_value encodes the pointer directly. */
 static int simplify_symbols(Elf_Shdr *sechdrs,
 			    unsigned int symindex,
 			    const char *strtab,