diff --git a/usr.sbin/bhyve/pci_xhci.c b/usr.sbin/bhyve/pci_xhci.c
--- a/usr.sbin/bhyve/pci_xhci.c
+++ b/usr.sbin/bhyve/pci_xhci.c
@@ -290,10 +290,10 @@
 };
 
 
-/* portregs and devices arrays are set up to start from idx=1 */
-#define	XHCI_PORTREG_PTR(x,n)	&(x)->portregs[(n)]
-#define	XHCI_DEVINST_PTR(x,n)	(x)->devices[(n)]
-#define	XHCI_SLOTDEV_PTR(x,n)	(x)->slots[(n)]
+/* port and slot numbering start from 1 */
+#define	XHCI_PORTREG_PTR(x,n)	&((x)->portregs[(n) - 1])
+#define	XHCI_DEVINST_PTR(x,n)	((x)->devices[(n) - 1])
+#define	XHCI_SLOTDEV_PTR(x,n)	((x)->slots[(n) - 1])
 
 #define	XHCI_HALTED(sc)		((sc)->opregs.usbsts & XHCI_STS_HCH)
 
@@ -2738,10 +2738,6 @@
 	sc->devices = calloc(XHCI_MAX_DEVS, sizeof(struct pci_xhci_dev_emu *));
 	sc->slots = calloc(XHCI_MAX_SLOTS, sizeof(struct pci_xhci_dev_emu *));
 
-	/* port and slot numbering start from 1 */
-	sc->devices--;
-	sc->slots--;
-
 	ndevices = 0;
 
 	slots_nvl = find_relative_config_node(nvl, "slot");
@@ -2835,7 +2831,6 @@
 
 portsfinal:
 	sc->portregs = calloc(XHCI_MAX_DEVS, sizeof(struct pci_xhci_portregs));
-	sc->portregs--;
 
 	if (ndevices > 0) {
 		for (i = 1; i <= XHCI_MAX_DEVS; i++) {
@@ -2851,8 +2846,8 @@
 		free(XHCI_DEVINST_PTR(sc, i));
 	}
 
-	free(sc->devices + 1);
-	free(sc->slots + 1);
+	free(sc->devices);
+	free(sc->slots);
 
 	return (-1);
 }