diff --git a/ChangeLog b/ChangeLog
index c9339e164..505c1cc0d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2010-12-31  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	* grub-core/partmap/amiga.c (GRUB_AMIGA_PART_MAGIC): New define.
+	(amiga_partition_map_iterate): Check "PART" magic to avoid a very long
+	loop in case of incorrect amiga partmap.
+
 2010-12-31  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* grub-core/partmap/amiga.c (GRUB_AMIGA_RDSK_MAGIC): New define.
diff --git a/grub-core/partmap/amiga.c b/grub-core/partmap/amiga.c
index a3ea3499c..1e0f23402 100644
--- a/grub-core/partmap/amiga.c
+++ b/grub-core/partmap/amiga.c
@@ -44,6 +44,7 @@ struct grub_amiga_partition
 {
   /* "PART".  */
   grub_uint8_t magic[4];
+#define GRUB_AMIGA_PART_MAGIC "PART"
   grub_int32_t size;
   grub_int32_t checksum;
   grub_uint32_t scsihost;
@@ -110,6 +111,9 @@ amiga_partition_map_iterate (grub_disk_t disk,
       if (grub_disk_read (disk, next, 0, sizeof (apart), &apart))
 	return grub_errno;
 
+      if (grub_memcmp (apart.magic, GRUB_AMIGA_PART_MAGIC,
+		       sizeof (apart.magic)) == 0)
+
       /* Calculate the first block and the size of the partition.  */
       part.start = (grub_be_to_cpu32 (apart.lowcyl)
 		    * grub_be_to_cpu32 (apart.heads)