diff --git a/ChangeLog b/ChangeLog
index 55fc31858..f9e7a4b6b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2013-11-22  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	* grub-core/disk/i386/pc/biosdisk.c (grub_biosdisk_open): Ensure
+	at compile time that enough of scratch size is available.
+
 2013-11-22  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* grub-core/kern/x86_64/efi/callwrap.S: Fix stack alignment.
diff --git a/grub-core/disk/i386/pc/biosdisk.c b/grub-core/disk/i386/pc/biosdisk.c
index 7458c7a0f..1689539cd 100644
--- a/grub-core/disk/i386/pc/biosdisk.c
+++ b/grub-core/disk/i386/pc/biosdisk.c
@@ -426,6 +426,10 @@ grub_biosdisk_open (const char *name, grub_disk_t disk)
   disk->total_sectors = total_sectors;
   /* Limit the max to 0x7f because of Phoenix EDD.  */
   disk->max_agglomerate = 0x7f >> GRUB_DISK_CACHE_BITS;
+  COMPILE_TIME_ASSERT ((0x7f >> GRUB_DISK_CACHE_BITS
+			<< (GRUB_DISK_SECTOR_BITS + GRUB_DISK_CACHE_BITS))
+		       + sizeof (struct grub_biosdisk_dap)
+		       < GRUB_MEMORY_MACHINE_SCRATCH_SIZE);
 
   disk->data = data;