3 files changed, 12 insertions, 4 deletions

diff --git a/sys/dev/bhnd/siba/siba.c b/sys/dev/bhnd/siba/siba.c
index c34fc4fca7d2..a508d3b39ae9 100644
--- a/sys/dev/bhnd/siba/siba.c
+++ b/sys/dev/bhnd/siba/siba.c
@@ -409,7 +409,7 @@ siba_get_region_addr(device_t dev, device_t child, bhnd_port_type port_type,
 			continue;
 
 		*addr = addrspace->sa_base;
-		*size = addrspace->sa_size;
+		*size = addrspace->sa_size - addrspace->sa_bus_reserved;
 		return (0);
 	}
 
diff --git a/sys/dev/bhnd/siba/siba_subr.c b/sys/dev/bhnd/siba/siba_subr.c
index e688006c2c66..5d9fc72b1dcd 100644
--- a/sys/dev/bhnd/siba/siba_subr.c
+++ b/sys/dev/bhnd/siba/siba_subr.c
@@ -243,11 +243,16 @@ siba_append_dinfo_region(struct siba_devinfo *dinfo, bhnd_port_type port_type,
 {
 	struct siba_addrspace	*sa;
 	struct siba_port	*port;
+	rman_res_t		 r_size;
 	
 	/* Verify that base + size will not overflow */
 	if (UINT32_MAX - size < base)
 		return (ERANGE);
 
+	/* Verify that size - bus_reserved will not underflow */
+	if (size < bus_reserved)
+		return (ERANGE);
+
 	/* Must not be 0-length */
 	if (size == 0)
 		return (EINVAL);
@@ -266,11 +271,12 @@ siba_append_dinfo_region(struct siba_devinfo *dinfo, bhnd_port_type port_type,
 	sa->sa_size = size;
 	sa->sa_sid = sid;
 	sa->sa_region_num = region_num;
-	
+	sa->sa_bus_reserved = bus_reserved;
+
 	/* Populate the resource list */
-	size -= bus_reserved;
+	r_size = size - bus_reserved;
 	sa->sa_rid = resource_list_add_next(&dinfo->resources, SYS_RES_MEMORY,
-	    base, base + size - 1, size);
+	    base, base + r_size - 1, r_size);
 
 	/* Append to target port */
 	STAILQ_INSERT_TAIL(&port->sp_addrs, sa, sa_link);
diff --git a/sys/dev/bhnd/siba/sibavar.h b/sys/dev/bhnd/siba/sibavar.h
index 784803c6cee4..2c9f14c50e78 100644
--- a/sys/dev/bhnd/siba/sibavar.h
+++ b/sys/dev/bhnd/siba/sibavar.h
@@ -97,6 +97,8 @@ struct siba_addrspace {
 	u_int		sa_region_num;	/**< bhnd region id */
 	uint8_t		sa_sid;		/**< siba-assigned address space ID */
 	int		sa_rid;		/**< bus resource id */
+	uint32_t	sa_bus_reserved;/**< number of bytes at high end of
+					  *  address space reserved for the bus */
 
 	STAILQ_ENTRY(siba_addrspace) sa_link;
 };