boot-directdisk: ensure generated MBR disk signature is non-zero

A zero MBR disk signature is generally seen as no signature and
another partitioning program might install a new signature.

Signed-off-by: Jonathan Liu <net147@gmail.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

diff --git a/meta/classes/boot-directdisk.bbclass b/meta/classes/boot-directdisk.bbclass
index c58c6f0c53bd34017acb6a0535bd9eb00cf8a637..0f64b44f87c601f60a821ae97f93e007ae555fe0 100644 (file)
--- a/meta/classes/boot-directdisk.bbclass
+++ b/meta/classes/boot-directdisk.bbclass
@@ -148,7 +148,11 @@ python do_bootdirectdisk() {
 def generate_disk_signature():
     import uuid
 
-    return str(uuid.uuid4())[:8]
+    while True:
+        signature = str(uuid.uuid4())[:8]
+
+        if signature != '00000000':
+            return signature
 
 def validate_disk_signature(d):
     import re