1 files changed, 4 insertions, 2 deletions

diff --git a/scripts/lib/wic/plugins/source/isoimage-isohybrid.py b/scripts/lib/wic/plugins/source/isoimage-isohybrid.py
index 95a54a09d2..11326a274b 100644
--- a/scripts/lib/wic/plugins/source/isoimage-isohybrid.py
+++ b/scripts/lib/wic/plugins/source/isoimage-isohybrid.py
@@ -336,11 +336,13 @@ class IsoImagePlugin(SourcePlugin):
                 (img_iso_dir, isodir)
             exec_cmd(install_cmd)
         else:
+            # Default to 100 blocks of extra space for file system overhead
+            esp_extra_blocks = int(source_params.get('esp_extra_blocks', '100'))
+
             du_cmd = "du -bks %s/EFI" % isodir
             out = exec_cmd(du_cmd)
             blocks = int(out.split()[0])
-            # Add some extra space for file system overhead
-            blocks += 100
+            blocks += esp_extra_blocks
             logger.debug("Added 100 extra blocks to %s to get to %d "
                          "total blocks", part.mountpoint, blocks)