6882425 delta for 6819150 breaks boot from DVD on a number of systems

2 files changed, 15 insertions, 2 deletions

diff --git a/usr/src/grub/grub-0.97/stage2/bios.c b/usr/src/grub/grub-0.97/stage2/bios.c
index ae70c306f9..c8365177eb 100644
--- a/usr/src/grub/grub-0.97/stage2/bios.c
+++ b/usr/src/grub/grub-0.97/stage2/bios.c
@@ -162,7 +162,7 @@ get_cdinfo (int drive, struct geometry *geometry)
           geometry->heads = 1;
           geometry->sectors = 15;
           geometry->sector_size = 2048;
-          geometry->total_sectors = MAXINT;
+          geometry->total_sectors = MAXUINT;
           return 1;
         }
       else
@@ -196,7 +196,7 @@ get_cdinfo (int drive, struct geometry *geometry)
       geometry->heads = 1;
       geometry->sectors = 15;
       geometry->sector_size = 2048;
-      geometry->total_sectors = MAXINT;
+      geometry->total_sectors = MAXUINT;
       return 1;
     }
   return 0;
diff --git a/usr/src/grub/grub-0.97/stage2/fsys_zfs.c b/usr/src/grub/grub-0.97/stage2/fsys_zfs.c
index 73e50b4273..a3f3888662 100644
--- a/usr/src/grub/grub-0.97/stage2/fsys_zfs.c
+++ b/usr/src/grub/grub-0.97/stage2/fsys_zfs.c
@@ -1302,6 +1302,19 @@ zfs_mount(void)
 	adjpl = P2ALIGN(adjpl, (uint64_t)sizeof (vdev_label_t));
 
 	for (label = 0; label < VDEV_LABELS; label++) {
+
+		/*
+		 * some eltorito stacks don't give us a size and
+		 * we end up setting the size to MAXUINT, further
+		 * some of these devices stop working once a single
+		 * read past the end has been issued. Checking
+		 * for a maximum part_length and skipping the backup
+		 * labels at the end of the slice/partition/device
+		 * avoids breaking down on such devices.
+		 */
+		if (part_length == MAXUINT && label == 2)
+			break;
+
 		uint64_t sector = vdev_label_start(adjpl,
 		    label) >> SPA_MINBLOCKSHIFT;