diff --git a/include/hw/s390x/s390-pci-bus.h b/include/hw/s390x/s390-pci-bus.h
index aa891c178d..2727e7bdef 100644
--- a/include/hw/s390x/s390-pci-bus.h
+++ b/include/hw/s390x/s390-pci-bus.h
@@ -313,7 +313,7 @@ typedef struct ZpciFmb {
 } ZpciFmb;
 QEMU_BUILD_BUG_MSG(offsetof(ZpciFmb, fmt0) != 48, "padding in ZpciFmb");
 
-#define ZPCI_DEFAULT_FN_GRP 0x20
+#define ZPCI_DEFAULT_FN_GRP 0xFF
 typedef struct S390PCIGroup {
     ClpRspQueryPciGrp zpci_group;
     int id;