diff --git a/build_library/cgpt.py b/build_library/cgpt.py
index 8ea741c279..3c811c9ffc 100755
--- a/build_library/cgpt.py
+++ b/build_library/cgpt.py
@@ -70,7 +70,9 @@ def LoadPartitionConfig(filename):
           part['fs_bytes'] = part['fs_blocks'] * metadata['fs_block_size']
 
           if part['fs_bytes'] > part['bytes']:
-            raise InvalidLayout('Filesystem may not be larger than partition')
+            raise InvalidLayout(
+                'Filesystem may not be larger than partition: %s %s: %d > %d' %
+                (layout_name, part['label'], part['fs_bytes'], part['bytes']))
   except KeyError as e:
     raise InvalidLayout('Layout is missing required entries: %s' % e)
 
diff --git a/build_library/legacy_disk_layout.json b/build_library/legacy_disk_layout.json
index 78b7bea5fe..ccd6291909 100644
--- a/build_library/legacy_disk_layout.json
+++ b/build_library/legacy_disk_layout.json
@@ -80,14 +80,14 @@
         "label":"ROOT-B",
         "type":"rootfs",
         "blocks":"4194304",
-        "fs_blocks":"217600"
+        "fs_blocks":"262144"
       },
       {
         "num": 3,
         "label":"ROOT-A",
         "type":"rootfs",
         "blocks":"4194304",
-        "fs_blocks":"217600"
+        "fs_blocks":"262144"
       }
     ],
     "usb": [
@@ -95,8 +95,8 @@
         "num": 3,
         "label":"ROOT-A",
         "type":"rootfs",
-        "blocks":"1757184",
-        "fs_blocks":"217600"
+        "blocks":"2113672",
+        "fs_blocks":"262144"
       },
       {
         "num": 5,
@@ -143,15 +143,15 @@
         "num": 3,
         "label":"ROOT-A",
         "type":"rootfs",
-        "blocks":"2097152",
-        "fs_blocks":"217600"
+        "blocks":"2113672",
+        "fs_blocks":"262144"
       },
       {
         "num": 5,
         "label":"ROOT-B",
         "type":"rootfs",
-        "blocks":"2097152",
-        "fs_blocks":"217600"
+        "blocks":"2113672",
+        "fs_blocks":"262144"
       }
     ],
     "recovery": [
@@ -165,8 +165,8 @@
         "num": 3,
         "label":"ROOT-A",
         "type":"rootfs",
-        "blocks":"1757184",
-        "fs_blocks":"217600"
+        "blocks":"2113672",
+        "fs_blocks":"262144"
       },
       {
         "num": 5,