Index: stand/i386/zfsboot/zfsboot.c
===================================================================
--- stand/i386/zfsboot/zfsboot.c
+++ stand/i386/zfsboot/zfsboot.c
@@ -166,9 +166,10 @@
 int
 main(void)
 {
-	unsigned i;
-	int auto_boot, fd, nextboot = 0;
 	struct disk_devdesc devdesc;
+	uint64_t pool_guid;
+	unsigned int i;
+	int auto_boot, fd, nextboot = 0;
 
 	bios_getmem();
 
@@ -215,8 +216,14 @@
 		if (devsw[i]->dv_init != NULL)
 			(devsw[i]->dv_init)();
 
-	disk_parsedev(&devdesc, boot_devname + 4, NULL);
+	if (zfs_get_bootguid(&pool_guid) == 0) {
+		bdev = malloc(sizeof (struct i386_devdesc));
+		bzero(bdev, sizeof (struct i386_devdesc));
+		bdev->dd.d_dev = &zfs_dev;
+		bdev->d_kind.zfs.pool_guid = pool_guid;
+	}
 
+	disk_parsedev(&devdesc, boot_devname + 4, NULL);
 	bootdev = MAKEBOOTDEV(dev_maj[DEVT_DISK], devdesc.d_slice + 1,
 	    devdesc.dd.d_unit,
 	    devdesc.d_partition >= 0 ? devdesc.d_partition : 0xff);
@@ -681,41 +688,31 @@
 }
 
 /*
- * Probe all disks to discover ZFS pools. The idea is to walk all possible
- * disk devices, however, we also need to identify possible boot pool.
- * For boot pool detection we have boot disk passed us from BIOS, recorded
- * in bootinfo.bi_bios_dev.
+ * Probe all disks to discover ZFS pools.
  */
 static void
 i386_zfs_probe(void)
 {
 	char devname[32];
-	int boot_unit;
 	struct i386_devdesc dev;
-	uint64_t pool_guid = 0;
+	int boot_unit;
 
 	dev.dd.d_dev = &bioshd;
+
 	/* Translate bios dev to our unit number. */
 	boot_unit = bd_bios2unit(bootinfo.bi_bios_dev);
 
 	/*
 	 * Open all the disks we can find and see if we can reconstruct
-	 * ZFS pools from them.
+	 * ZFS pools from them.  Start with the boot disk.
 	 */
+	snprintf(devname, sizeof (devname), "%s%d:", bioshd.dv_name, boot_unit);
+	zfs_probe_dev(devname, NULL);
 	for (dev.dd.d_unit = 0; bd_unit2bios(&dev) >= 0; dev.dd.d_unit++) {
-		snprintf(devname, sizeof (devname), "%s%d:", bioshd.dv_name,
-		    dev.dd.d_unit);
-		/* If this is not boot disk, use generic probe. */
-		if (dev.dd.d_unit != boot_unit)
+		if (dev.dd.d_unit != boot_unit) {
+			snprintf(devname, sizeof (devname), "%s%d:",
+			    bioshd.dv_name, dev.dd.d_unit);
 			zfs_probe_dev(devname, NULL);
-		else
-			zfs_probe_dev(devname, &pool_guid);
-
-		if (pool_guid != 0 && bdev == NULL) {
-			bdev = malloc(sizeof (struct i386_devdesc));
-			bzero(bdev, sizeof (struct i386_devdesc));
-			bdev->dd.d_dev = &zfs_dev;
-			bdev->d_kind.zfs.pool_guid = pool_guid;
 		}
 	}
 }
Index: stand/libsa/zfs/libzfs.h
===================================================================
--- stand/libsa/zfs/libzfs.h
+++ stand/libsa/zfs/libzfs.h
@@ -53,6 +53,7 @@
 char	*zfs_fmtdev(void *vdev);
 int	zfs_probe_dev(const char *devname, uint64_t *pool_guid);
 int	zfs_list(const char *name);
+int	zfs_get_bootguid(uint64_t *pool_guid);
 int	zfs_get_bootonce(void *, const char *, char *, size_t);
 int	zfs_get_bootenv(void *, nvlist_t **);
 int	zfs_set_bootenv(void *, nvlist_t *);
Index: stand/libsa/zfs/zfs.c
===================================================================
--- stand/libsa/zfs/zfs.c
+++ stand/libsa/zfs/zfs.c
@@ -767,6 +767,20 @@
 	return (0);
 }
 
+int
+zfs_get_bootguid(uint64_t *pool_guid)
+{
+	spa_t *spa;
+
+	*pool_guid = 0;
+	spa = spa_first_bootable();
+	if (spa != NULL) {
+		*pool_guid = spa->spa_guid;
+		return (0);
+	}
+	return (ENXIO);
+}
+
 /*
  * Return bootenv nvlist from pool label.
  */
Index: stand/libsa/zfs/zfsimpl.c
===================================================================
--- stand/libsa/zfs/zfsimpl.c
+++ stand/libsa/zfs/zfsimpl.c
@@ -1342,6 +1342,21 @@
 	return (rc);
 }
 
+static spa_t *
+spa_first_bootable(void)
+{
+	spa_t *spa;
+
+	/* Pick the first pool with "bootfs" property explicitly set, if any. */
+	STAILQ_FOREACH(spa, &zfs_pools, spa_link) {
+		if (spa->spa_bootfs != 0)
+			return (spa);
+	}
+
+	/* Fall back to the first pool if there is one. */
+	return (STAILQ_FIRST(&zfs_pools));
+}
+
 static spa_t *
 spa_find_by_guid(uint64_t guid)
 {
@@ -1374,7 +1389,7 @@
 		return (NULL);
 
 	if (dev->pool_guid == 0)
-		return (STAILQ_FIRST(&zfs_pools));
+		return (spa_first_bootable());
 
 	return (spa_find_by_guid(dev->pool_guid));
 }
@@ -3294,40 +3309,35 @@
 static int
 zfs_get_root(const spa_t *spa, uint64_t *objid)
 {
-	dnode_phys_t dir, propdir;
-	uint64_t props, bootfs, root;
+	dnode_phys_t dir;
+	uint64_t root;
 
 	*objid = 0;
 
-	/*
-	 * Start with the MOS directory object.
-	 */
-	if (objset_get_dnode(spa, spa->spa_mos,
-	    DMU_POOL_DIRECTORY_OBJECT, &dir)) {
-		printf("ZFS: can't read MOS object directory\n");
-		return (EIO);
-	}
-
-	/*
-	 * Lookup the pool_props and see if we can find a bootfs.
-	 */
-	if (zap_lookup(spa, &dir, DMU_POOL_PROPS,
-	    sizeof(props), 1, &props) == 0 &&
-	    objset_get_dnode(spa, spa->spa_mos, props, &propdir) == 0 &&
-	    zap_lookup(spa, &propdir, "bootfs",
-	    sizeof(bootfs), 1, &bootfs) == 0 && bootfs != 0) {
-		*objid = bootfs;
+	/* See if the pool has bootfs set. */
+	if (spa->spa_bootfs != 0) {
+		*objid = spa->spa_bootfs;
 		return (0);
 	}
+
 	/*
 	 * Lookup the root dataset directory
 	 */
+	if (objset_get_dnode(spa, spa->spa_mos, DMU_POOL_DIRECTORY_OBJECT,
+	    &dir)) {
+		printf("ZFS: failed to read pool %s directory object\n",
+		    spa->spa_name);
+		return (EIO);
+	}
 	if (zap_lookup(spa, &dir, DMU_POOL_ROOT_DATASET,
-	    sizeof(root), 1, &root) ||
-	    objset_get_dnode(spa, spa->spa_mos, root, &dir)) {
+	    sizeof(root), 1, &root) != 0) {
 		printf("ZFS: can't find root dsl_dir\n");
 		return (EIO);
 	}
+	if (objset_get_dnode(spa, spa->spa_mos, root, &dir) != 0) {
+		printf("ZFS: can't read root dsl_dir\n");
+		return (EIO);
+	}
 
 	/*
 	 * Use the information from the dataset directory's bonus buffer
@@ -3471,8 +3481,8 @@
 zfs_spa_init(spa_t *spa)
 {
 	struct uberblock checkpoint;
-	dnode_phys_t dir;
-	uint64_t config_object;
+	dnode_phys_t dir, propdir;
+	uint64_t config_object, props;
 	nvlist_t *nvlist;
 	int rc;
 
@@ -3502,6 +3512,22 @@
 		return (rc);
 	}
 
+	/*
+	 * Lookup the pool_props and see if we can find a bootfs.
+	 */
+	if (zap_lookup(spa, &dir, DMU_POOL_PROPS,
+	    sizeof(props), 1, &props) == 0) {
+	    rc = objset_get_dnode(spa, spa->spa_mos, props, &propdir);
+	    if (rc != 0) {
+		printf("ZFS: failed to read pool %s properties object\n",
+		    spa->spa_name);
+		return (rc);
+	    }
+	    spa->spa_bootfs = 0;
+	    (void)zap_lookup(spa, &propdir, "bootfs",
+		sizeof(spa->spa_bootfs), 1, &spa->spa_bootfs);
+	}
+
 	rc = zap_lookup(spa, &dir, DMU_POOL_CONFIG,
 	    sizeof (config_object), 1, &config_object);
 	if (rc != 0) {
Index: sys/cddl/boot/zfs/zfsimpl.h
===================================================================
--- sys/cddl/boot/zfs/zfsimpl.h
+++ sys/cddl/boot/zfs/zfsimpl.h
@@ -2030,6 +2030,7 @@
 	char		*spa_name;	/* pool name */
 	uint64_t	spa_guid;	/* pool guid */
 	uint64_t	spa_txg;	/* most recent transaction */
+	uint64_t	spa_bootfs;	/* bootfs object id */
 	struct uberblock *spa_uberblock;	/* best uberblock so far */
 	vdev_t		*spa_root_vdev;	/* toplevel vdev container */
 	objset_phys_t	*spa_mos;	/* MOS for this pool */