diff --git a/large_mac_iso.patch b/large_mac_iso.patch
index d30791c..8008d27 100644
--- a/large_mac_iso.patch
+++ b/large_mac_iso.patch
@@ -1,3 +1,9 @@
+From: Adam Majer <amajer@suse.com>
+Date: 2020-05-11 11:47:23+0000
+
+Fix an integer overflow in partition table calculation when chrp-boot
+is enabled and a large ISO image is created.
+
 Index: cdrtools-3.02/mkisofs/mac_label.c
 ===================================================================
 --- cdrtools-3.02.orig/mkisofs/mac_label.c
diff --git a/schily.spec b/schily.spec
index e170ebc..f956727 100644
--- a/schily.spec
+++ b/schily.spec
@@ -446,9 +446,7 @@ limitations on file size and supports to edit large files (files >2
 GB).
 
 %prep
-%setup -qn %name-%rver
-%patch -P 1 -P 2 -p1
-%patch3 -p1
+%autosetup -n %name-%rver -p1
 find . "(" -type d -o -type f ")" -exec chmod u+w "{}" "+"
 
 cp %{SOURCE1} .