kbuild: improve error from file2alias

The original errormessage was just plain unreadable.

Sample error message after this update (not for real - I provoked it):

FATAL: drivers/net/s2io: sizeof(struct pci_device_id)=33 is not a modulo of the
size of section __mod_pci_device_table=160.
Fix definition of struct pci_device_id in mod_devicetable.h

Before a warning was generated - this is now a fatal error.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

scripts/mod/file2alias.c

@@ -52,6 +52,23 @@ do {                                                            \
                 sprintf(str + strlen(str), "*");                \
 } while(0)
 
+/**
+ * Check that sizeof(device_id type) are consistent with size of section
+ * in .o file. If in-consistent then userspace and kernel does not agree
+ * on actual size which is a bug.
+ **/
+static void device_id_size_check(const char *modname, const char *device_id,
+				 unsigned long size, unsigned long id_size)
+{
+	if (size % id_size || size < id_size) {
+		fatal("%s: sizeof(struct %s_device_id)=%lu is not a modulo "
+		      "of the size of section __mod_%s_device_table=%lu.\n"
+		      "Fix definition of struct %s_device_id "
+		      "in mod_devicetable.h\n",
+		      modname, device_id, id_size, device_id, size, device_id);
+	}
+}
+
 /* USB is special because the bcdDevice can be matched against a numeric range */
 /* Looks like "usb:vNpNdNdcNdscNdpNicNiscNipN" */
 static void do_usb_entry(struct usb_device_id *id,
@@ -152,10 +169,8 @@ static void do_usb_table(void *symval, unsigned long size,
 	unsigned int i;
 	const unsigned long id_size = sizeof(struct usb_device_id);
 
-	if (size % id_size || size < id_size) {
-		warn("%s ids %lu bad size "
-		     "(each on %lu)\n", mod->name, size, id_size);
-	}
+	device_id_size_check(mod->name, "usb", size, id_size);
+
 	/* Leave last one: it's the terminator. */
 	size -= id_size;
 
@@ -434,6 +449,7 @@ static inline int sym_is(const char *symbol, const char *name)
 
 static void do_table(void *symval, unsigned long size,
 		     unsigned long id_size,
+		     const char *device_id,
 		     void *function,
 		     struct module *mod)
 {
@@ -441,10 +457,7 @@ static void do_table(void *symval, unsigned long size,
 	char alias[500];
 	int (*do_entry)(const char *, void *entry, char *alias) = function;
 
-	if (size % id_size || size < id_size) {
-		warn("%s ids %lu bad size "
-		     "(each on %lu)\n", mod->name, size, id_size);
-	}
+	device_id_size_check(mod->name, device_id, size, id_size);
 	/* Leave last one: it's the terminator. */
 	size -= id_size;
 
@@ -476,40 +489,51 @@ void handle_moddevtable(struct module *mod, struct elf_info *info,
 		+ sym->st_value;
 
 	if (sym_is(symname, "__mod_pci_device_table"))
-		do_table(symval, sym->st_size, sizeof(struct pci_device_id),
+		do_table(symval, sym->st_size,
+			 sizeof(struct pci_device_id), "pci",
 			 do_pci_entry, mod);
 	else if (sym_is(symname, "__mod_usb_device_table"))
 		/* special case to handle bcdDevice ranges */
 		do_usb_table(symval, sym->st_size, mod);
 	else if (sym_is(symname, "__mod_ieee1394_device_table"))
-		do_table(symval, sym->st_size, sizeof(struct ieee1394_device_id),
+		do_table(symval, sym->st_size,
+			 sizeof(struct ieee1394_device_id), "ieee1394",
 			 do_ieee1394_entry, mod);
 	else if (sym_is(symname, "__mod_ccw_device_table"))
-		do_table(symval, sym->st_size, sizeof(struct ccw_device_id),
+		do_table(symval, sym->st_size,
+			 sizeof(struct ccw_device_id), "ccw",
 			 do_ccw_entry, mod);
 	else if (sym_is(symname, "__mod_serio_device_table"))
-		do_table(symval, sym->st_size, sizeof(struct serio_device_id),
+		do_table(symval, sym->st_size,
+			 sizeof(struct serio_device_id), "serio",
 			 do_serio_entry, mod);
 	else if (sym_is(symname, "__mod_pnp_device_table"))
-		do_table(symval, sym->st_size, sizeof(struct pnp_device_id),
+		do_table(symval, sym->st_size,
+			 sizeof(struct pnp_device_id), "pnp",
 			 do_pnp_entry, mod);
 	else if (sym_is(symname, "__mod_pnp_card_device_table"))
-		do_table(symval, sym->st_size, sizeof(struct pnp_card_device_id),
+		do_table(symval, sym->st_size,
+			 sizeof(struct pnp_card_device_id), "pnp_card",
 			 do_pnp_card_entry, mod);
 	else if (sym_is(symname, "__mod_pcmcia_device_table"))
-		do_table(symval, sym->st_size, sizeof(struct pcmcia_device_id),
+		do_table(symval, sym->st_size,
+			 sizeof(struct pcmcia_device_id), "pcmcia",
 			 do_pcmcia_entry, mod);
         else if (sym_is(symname, "__mod_of_device_table"))
-		do_table(symval, sym->st_size, sizeof(struct of_device_id),
+		do_table(symval, sym->st_size,
+			 sizeof(struct of_device_id), "of",
 			 do_of_entry, mod);
         else if (sym_is(symname, "__mod_vio_device_table"))
-		do_table(symval, sym->st_size, sizeof(struct vio_device_id),
+		do_table(symval, sym->st_size,
+			 sizeof(struct vio_device_id), "vio",
 			 do_vio_entry, mod);
 	else if (sym_is(symname, "__mod_i2c_device_table"))
-		do_table(symval, sym->st_size, sizeof(struct i2c_device_id),
+		do_table(symval, sym->st_size,
+			 sizeof(struct i2c_device_id), "i2c",
 			 do_i2c_entry, mod);
 	else if (sym_is(symname, "__mod_input_device_table"))
-		do_table(symval, sym->st_size, sizeof(struct input_device_id),
+		do_table(symval, sym->st_size,
+			 sizeof(struct input_device_id), "input",
 			 do_input_entry, mod);
 }