kbuild/modules: Track versions of exported symbols

Store the information on the checksum alongside the rest of the 
information on exported symbols. To actually use them, we need
something to check them against first, though ;)

Also, fix some conditional debug code to actually compile.

include/linux/module.h

@@ -119,6 +119,7 @@ struct kernel_symbol_group
 
 	unsigned int num_syms;
 	const struct kernel_symbol *syms;
+	const unsigned long *crcs;
 };
 
 /* Given an address, look for it in the exception tables */

kernel/module.c

@@ -916,7 +916,7 @@ static void layout_sections(struct module *mod,
 			    || strstr(secstrings + s->sh_name, ".init"))
 				continue;
 			s->sh_entsize = get_offset(&mod->core_size, s);
-			DEBUGP("\t%s\n", name);
+			DEBUGP("\t%s\n", secstrings + s->sh_name);
 		}
 	}
 
@@ -932,7 +932,7 @@ static void layout_sections(struct module *mod,
 				continue;
 			s->sh_entsize = (get_offset(&mod->init_size, s)
 					 | INIT_OFFSET_MASK);
-			DEBUGP("\t%s\n", name);
+			DEBUGP("\t%s\n", secstrings + s->sh_name);
 		}
 	}
 }
@@ -976,7 +976,8 @@ static struct module *load_module(void *umod,
 	Elf_Shdr *sechdrs;
 	char *secstrings, *args;
 	unsigned int i, symindex, exportindex, strindex, setupindex, exindex,
-		modindex, obsparmindex, licenseindex, gplindex, vmagindex;
+		modindex, obsparmindex, licenseindex, gplindex, vmagindex,
+		crcindex, gplcrcindex;
 	long arglen;
 	struct module *mod;
 	long err = 0;
@@ -1012,7 +1013,8 @@ static struct module *load_module(void *umod,
 
 	/* May not export symbols, or have setup params, so these may
            not exist */
-	exportindex = setupindex = obsparmindex = gplindex = licenseindex = 0;
+	exportindex = setupindex = obsparmindex = gplindex = licenseindex 
+		= crcindex = gplcrcindex = 0;
 
 	/* And these should exist, but gcc whinges if we don't init them */
 	symindex = strindex = exindex = modindex = vmagindex = 0;
@@ -1045,6 +1047,16 @@ static struct module *load_module(void *umod,
 			/* Exported symbols. (GPL) */
 			DEBUGP("GPL symbols found in section %u\n", i);
 			gplindex = i;
+		} else if (strcmp(secstrings+sechdrs[i].sh_name, "__kcrctab")
+			   == 0) {
+			/* Exported symbols CRCs. */
+			DEBUGP("CRC table in section %u\n", i);
+			crcindex = i;
+		} else if (strcmp(secstrings+sechdrs[i].sh_name, "__kcrctab_gpl")
+			   == 0) {
+			/* Exported symbols CRCs. (GPL)*/
+			DEBUGP("CRC table in section %u\n", i);
+			gplcrcindex = i;
 		} else if (strcmp(secstrings+sechdrs[i].sh_name, "__param")
 			   == 0) {
 			/* Setup parameter info */
@@ -1192,9 +1204,11 @@ 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;
 	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;
 
 	/* Set up exception table */
 	if (exindex) {
@@ -1497,6 +1511,10 @@ extern const struct kernel_symbol __start___ksymtab[];
 extern const struct kernel_symbol __stop___ksymtab[];
 extern const struct kernel_symbol __start___ksymtab_gpl[];
 extern const struct kernel_symbol __stop___ksymtab_gpl[];
+extern const unsigned long __start___kcrctab[];
+extern const unsigned long __stop___kcrctab[];
+extern const unsigned long __start___kcrctab_gpl[];
+extern const unsigned long __stop___kcrctab_gpl[];
 
 static struct kernel_symbol_group kernel_symbols, kernel_gpl_symbols;
 
@@ -1505,12 +1523,14 @@ static int __init symbols_init(void)
 	/* Add kernel symbols to symbol table */
 	kernel_symbols.num_syms = (__stop___ksymtab - __start___ksymtab);
 	kernel_symbols.syms = __start___ksymtab;
+	kernel_symbols.crcs = __start___kcrctab;
 	kernel_symbols.gplonly = 0;
 	list_add(&kernel_symbols.list, &symbols);
 
 	kernel_gpl_symbols.num_syms = (__stop___ksymtab_gpl
 				       - __start___ksymtab_gpl);
 	kernel_gpl_symbols.syms = __start___ksymtab_gpl;
+	kernel_gpl_symbols.crcs = __start___kcrctab_gpl;
 	kernel_gpl_symbols.gplonly = 1;
 	list_add(&kernel_gpl_symbols.list, &symbols);