=== modified file 'grub-core/partmap/sun.c'
--- grub-core/partmap/sun.c	2010-09-14 19:07:39 +0000
+++ grub-core/partmap/sun.c	2010-12-17 05:04:53 +0000
@@ -67,19 +67,27 @@
 
 static struct grub_partition_map grub_sun_partition_map;
 
-/* Verify checksum (true=ok).  */
-static int
-grub_sun_is_valid (struct grub_sun_block *label)
+/* test whether we're dealing with a valid Sun disklabel */
+static grub_err_t
+grub_sun_test (struct grub_sun_block *label)
 {
   grub_uint16_t *pos;
   grub_uint16_t sum = 0;
 
+  if (GRUB_PARTMAP_SUN_MAGIC != grub_be_to_cpu16 (label->magic))
+    return grub_error (GRUB_ERR_BAD_PART_TABLE, "not a sun partition table");
+
   for (pos = (grub_uint16_t *) label;
        pos < (grub_uint16_t *) (label + 1);
        pos++)
     sum ^= *pos;
 
-  return ! sum;
+  /* Maybe another error value would be better, because partition
+     table _is_ recognized but invalid.  */
+  if (sum)
+    return grub_error (GRUB_ERR_BAD_PART_TABLE, "invalid checksum");
+
+  return GRUB_ERR_NONE;
 }
 
 static grub_err_t
@@ -98,14 +106,9 @@
   if (err)
     return err;
 
-  if (GRUB_PARTMAP_SUN_MAGIC != grub_be_to_cpu16 (block.magic))
-    return grub_error (GRUB_ERR_BAD_PART_TABLE, "not a sun partition table");
+  if (GRUB_ERR_NONE != (err = grub_sun_test(&block)))
+    return err;
 
-  if (! grub_sun_is_valid (&block))
-      return grub_error (GRUB_ERR_BAD_PART_TABLE, "invalid checksum");
-  
-  /* Maybe another error value would be better, because partition
-     table _is_ recognized but invalid.  */
   for (partnum = 0; partnum < GRUB_PARTMAP_SUN_MAX_PARTS; partnum++)
     {
       struct grub_sun_partition_descriptor *desc;