diff --git a/include/boot/loaders_layout.h b/include/boot/loaders_layout.h
index 6426e555..9ae55303 100644
--- a/include/boot/loaders_layout.h
+++ b/include/boot/loaders_layout.h
@@ -33,6 +33,7 @@
 #define STAGE2_DUMPER_SIZE_V1		_AC(0x1000, UL)
 #define STAGE2_DUMPER_SIZE_V2		_AC(0x2000, UL)
 #define STAGE2_DUMPER_SIZE_V3		_AC(0x3000, UL)
+#define STAGE2_DUMPER_SIZE_ZLIB		_AC(0x8000, UL)
 
 #define STAGE3_ENTRY			_AC(0xa000, UL)
 
diff --git a/zdump/df_s390.c b/zdump/df_s390.c
index d2831464..92dfa9c9 100644
--- a/zdump/df_s390.c
+++ b/zdump/df_s390.c
@@ -160,7 +160,10 @@ void df_s390_dumper_read(struct zg_fh *fh, int blk_size,
 			dumper->size = STAGE2_DUMPER_SIZE_V1;
 		break;
 	case 2:
-		dumper->size = STAGE2_DUMPER_SIZE_V2;
+		if (strncmp(dumper->magic, DF_S390_DUMPER_MAGIC_EXT, 7) == 0)
+			dumper->size = STAGE2_DUMPER_SIZE_ZLIB;
+		else
+			dumper->size = STAGE2_DUMPER_SIZE_V2;
 		break;
 	case 3:
 	default: