--- a/block/partitions/Kconfig
+++ b/block/partitions/Kconfig
@@ -101,6 +101,13 @@ config ATARI_PARTITION
 	  Say Y here if you would like to use hard disks under Linux which
 	  were partitioned under the Atari OS.
 
+config FIT_PARTITION
+	bool "Flattened-Image-Tree (FIT) partition support" if PARTITION_ADVANCED
+	default n
+	help
+	  Say Y here if your system needs to mount the filesystem part of
+	  a Flattened-Image-Tree (FIT) image commonly used with Das U-Boot.
+
 config IBM_PARTITION
 	bool "IBM disk label and partition support"
 	depends on PARTITION_ADVANCED && S390
--- a/block/partitions/Makefile
+++ b/block/partitions/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_ACORN_PARTITION) += acorn.o
 obj-$(CONFIG_AMIGA_PARTITION) += amiga.o
 obj-$(CONFIG_ATARI_PARTITION) += atari.o
 obj-$(CONFIG_AIX_PARTITION) += aix.o
+obj-$(CONFIG_FIT_PARTITION) += fit.o
 obj-$(CONFIG_CMDLINE_PARTITION) += cmdline.o
 obj-$(CONFIG_MAC_PARTITION) += mac.o
 obj-$(CONFIG_LDM_PARTITION) += ldm.o
--- a/drivers/mtd/ubi/block.c
+++ b/drivers/mtd/ubi/block.c
@@ -396,7 +396,7 @@ int ubiblock_create(struct ubi_volume_in
 	dev->leb_size = vi->usable_leb_size;
 
 	/* Initialize the gendisk of this ubiblock device */
-	gd = alloc_disk(1);
+	gd = alloc_disk(0);
 	if (!gd) {
 		pr_err("UBI: block: alloc_disk failed\n");
 		ret = -ENODEV;
@@ -413,6 +413,7 @@ int ubiblock_create(struct ubi_volume_in
 		goto out_put_disk;
 	}
 	gd->private_data = dev;
+	gd->flags |= GENHD_FL_EXT_DEVT;
 	sprintf(gd->disk_name, "ubiblock%d_%d", dev->ubi_num, dev->vol_id);
 	set_capacity(gd, disk_capacity);
 	dev->gd = gd;
--- a/block/partition-generic.c
+++ b/block/partition-generic.c
@@ -18,6 +18,7 @@
 #include <linux/ctype.h>
 #include <linux/genhd.h>
 #include <linux/blktrace_api.h>
+#include <linux/root_dev.h>
 
 #include "partitions/check.h"
 
@@ -634,6 +635,8 @@ rescan:
 		if (state->parts[p].flags & ADDPART_FLAG_RAID)
 			md_autodetect_dev(part_to_dev(part)->devt);
 #endif
+		if ((state->parts[p].flags & ADDPART_FLAG_ROOTDEV) && ROOT_DEV == 0)
+			ROOT_DEV = part_to_dev(part)->devt;
 	}
 	free_partitions(state);
 	return 0;
--- a/block/partitions/check.c
+++ b/block/partitions/check.c
@@ -33,6 +33,7 @@
 #include "ibm.h"
 #include "ultrix.h"
 #include "efi.h"
+#include "fit.h"
 #include "karma.h"
 #include "sysv68.h"
 #include "cmdline.h"
@@ -73,6 +74,9 @@ static int (*check_part[])(struct parsed
 #ifdef CONFIG_EFI_PARTITION
 	efi_partition,		/* this must come before msdos */
 #endif
+#ifdef CONFIG_FIT_PARTITION
+	fit_partition,
+#endif
 #ifdef CONFIG_SGI_PARTITION
 	sgi_partition,
 #endif
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -614,6 +614,7 @@ struct unixware_disklabel {
 #define ADDPART_FLAG_NONE	0
 #define ADDPART_FLAG_RAID	1
 #define ADDPART_FLAG_WHOLEDISK	2
+#define ADDPART_FLAG_ROOTDEV	4
 
 extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
 extern void blk_free_devt(dev_t devt);
--- /dev/null
+++ b/block/partitions/fit.h
@@ -0,0 +1,2 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+int fit_partition(struct parsed_partitions *);