kbuild: Modversions fixes

Fix the case where no CRCs are supplied (OK, but taints kernel), and
only print one tainted message (otherwise --force gives hundreds of them).

kernel/module.c

@@ -737,12 +737,9 @@ static int check_version(Elf_Shdr *sechdrs,
 	unsigned int i, num_versions;
 	struct modversion_info *versions;
 
-	if (!ksg->crcs) { 
-		printk("%s: no CRC for \"%s\" [%s] found: kernel tainted.\n",
-		       mod->name, symname, 
-		       ksg->owner ? ksg->owner->name : "kernel");
-		goto taint;
-	}
+	/* Exporting module didn't supply crcs?  OK, we're already tainted. */
+	if (!ksg->crcs)
+		return 1;
 
 	crc = ksg->crcs[symidx];
 
@@ -763,10 +760,11 @@ static int check_version(Elf_Shdr *sechdrs,
 		return 0;
 	}
 	/* Not in module's version table.  OK, but that taints the kernel. */
-	printk("%s: no version for \"%s\" found: kernel tainted.\n",
-	       mod->name, symname);
- taint:
-	tainted |= TAINT_FORCED_MODULE;
+	if (!(tainted & TAINT_FORCED_MODULE)) {
+		printk("%s: no version for \"%s\" found: kernel tainted.\n",
+		       mod->name, symname);
+		tainted |= TAINT_FORCED_MODULE;
+	}
 	return 1;
 }
 #else
@@ -1273,11 +1271,23 @@ static struct module *load_module(void *umod,
 	mod->symbols.num_syms = (sechdrs[exportindex].sh_size
 				 / sizeof(*mod->symbols.syms));
 	mod->symbols.syms = (void *)sechdrs[exportindex].sh_addr;
-	mod->symbols.crcs = (void *)sechdrs[crcindex].sh_addr;
+	if (crcindex)
+		mod->symbols.crcs = (void *)sechdrs[crcindex].sh_addr;
+
 	mod->gpl_symbols.num_syms = (sechdrs[gplindex].sh_size
 				 / sizeof(*mod->symbols.syms));
 	mod->gpl_symbols.syms = (void *)sechdrs[gplindex].sh_addr;
-	mod->gpl_symbols.crcs = (void *)sechdrs[gplcrcindex].sh_addr;
+	if (gplcrcindex)
+		mod->gpl_symbols.crcs = (void *)sechdrs[gplcrcindex].sh_addr;
+
+#ifdef CONFIG_MODVERSIONS
+	if ((mod->symbols.num_syms && !crcindex)
+	    || (mod->gpl_symbols.num_syms && !gplcrcindex))
+		printk(KERN_WARNING "%s: No versions for exported symbols."
+		       " Tainting kernel.\n", mod->name);
+		tainted |= TAINT_FORCED_MODULE;
+	}
+#endif
 
 	/* Set up exception table */
 	if (exindex) {