diff --git a/drivers/md/md.c b/drivers/md/md.c
index 2a456a5d59a8..539f08885e7f 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1183,6 +1183,7 @@ static int super_90_validate(struct mddev *mddev, struct md_rdev *rdev)
 			    desc->raid_disk < mddev->raid_disks */) {
 			set_bit(In_sync, &rdev->flags);
 			rdev->raid_disk = desc->raid_disk;
+			rdev->saved_raid_disk = desc->raid_disk;
 		} else if (desc->state & (1<<MD_DISK_ACTIVE)) {
 			/* active but not in sync implies recovery up to
 			 * reshape position.  We don't know exactly where
@@ -1681,10 +1682,14 @@ static int super_1_validate(struct mddev *mddev, struct md_rdev *rdev)
 			set_bit(Faulty, &rdev->flags);
 			break;
 		default:
+			rdev->saved_raid_disk = role;
 			if ((le32_to_cpu(sb->feature_map) &
-			     MD_FEATURE_RECOVERY_OFFSET))
+			     MD_FEATURE_RECOVERY_OFFSET)) {
 				rdev->recovery_offset = le64_to_cpu(sb->recovery_offset);
-			else
+				if (!(le32_to_cpu(sb->feature_map) &
+				      MD_FEATURE_RECOVERY_BITMAP))
+					rdev->saved_raid_disk = -1;
+			} else
 				set_bit(In_sync, &rdev->flags);
 			rdev->raid_disk = role;
 			break;
@@ -1746,6 +1751,9 @@ static void super_1_sync(struct mddev *mddev, struct md_rdev *rdev)
 			cpu_to_le32(MD_FEATURE_RECOVERY_OFFSET);
 		sb->recovery_offset =
 			cpu_to_le64(rdev->recovery_offset);
+		if (rdev->saved_raid_disk >= 0 && mddev->bitmap)
+			sb->feature_map |=
+				cpu_to_le32(MD_FEATURE_RECOVERY_BITMAP);
 	}
 	if (test_bit(Replacement, &rdev->flags))
 		sb->feature_map |=
@@ -2487,8 +2495,7 @@ repeat:
 		if (rdev->sb_loaded != 1)
 			continue; /* no noise on spare devices */
 
-		if (!test_bit(Faulty, &rdev->flags) &&
-		    rdev->saved_raid_disk == -1) {
+		if (!test_bit(Faulty, &rdev->flags)) {
 			md_super_write(mddev,rdev,
 				       rdev->sb_start, rdev->sb_size,
 				       rdev->sb_page);
@@ -2504,11 +2511,9 @@ repeat:
 				rdev->badblocks.size = 0;
 			}
 
-		} else if (test_bit(Faulty, &rdev->flags))
+		} else
 			pr_debug("md: %s (skipping faulty)\n",
 				 bdevname(rdev->bdev, b));
-		else
-			pr_debug("(skipping incremental s/r ");
 
 		if (mddev->level == LEVEL_MULTIPATH)
 			/* only need to write one superblock... */
@@ -2624,6 +2629,8 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len)
 	 *  blocked - sets the Blocked flags
 	 *  -blocked - clears the Blocked and possibly simulates an error
 	 *  insync - sets Insync providing device isn't active
+	 *  -insync - clear Insync for a device with a slot assigned,
+	 *            so that it gets rebuilt based on bitmap
 	 *  write_error - sets WriteErrorSeen
 	 *  -write_error - clears WriteErrorSeen
 	 */
@@ -2672,6 +2679,11 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len)
 	} else if (cmd_match(buf, "insync") && rdev->raid_disk == -1) {
 		set_bit(In_sync, &rdev->flags);
 		err = 0;
+	} else if (cmd_match(buf, "-insync") && rdev->raid_disk >= 0) {
+		clear_bit(In_sync, &rdev->flags);
+		rdev->saved_raid_disk = rdev->raid_disk;
+		rdev->raid_disk = -1;
+		err = 0;
 	} else if (cmd_match(buf, "write_error")) {
 		set_bit(WriteErrorSeen, &rdev->flags);
 		err = 0;
@@ -5780,6 +5792,7 @@ static int add_new_disk(struct mddev * mddev, mdu_disk_info_t *info)
 				clear_bit(Bitmap_sync, &rdev->flags);
 			} else
 				rdev->raid_disk = -1;
+			rdev->saved_raid_disk = rdev->raid_disk;
 		} else
 			super_types[mddev->major_version].
 				validate_super(mddev, rdev);
@@ -5792,11 +5805,6 @@ static int add_new_disk(struct mddev * mddev, mdu_disk_info_t *info)
 			return -EINVAL;
 		}
 
-		if (test_bit(In_sync, &rdev->flags))
-			rdev->saved_raid_disk = rdev->raid_disk;
-		else
-			rdev->saved_raid_disk = -1;
-
 		clear_bit(In_sync, &rdev->flags); /* just to be sure */
 		if (info->state & (1<<MD_DISK_WRITEMOSTLY))
 			set_bit(WriteMostly, &rdev->flags);
@@ -7948,14 +7956,10 @@ void md_reap_sync_thread(struct mddev *mddev)
 		mddev->pers->finish_reshape(mddev);
 
 	/* If array is no-longer degraded, then any saved_raid_disk
-	 * information must be scrapped.  Also if any device is now
-	 * In_sync we must scrape the saved_raid_disk for that device
-	 * do the superblock for an incrementally recovered device
-	 * written out.
+	 * information must be scrapped.
 	 */
-	rdev_for_each(rdev, mddev)
-		if (!mddev->degraded ||
-		    test_bit(In_sync, &rdev->flags))
+	if (!mddev->degraded)
+		rdev_for_each(rdev, mddev)
 			rdev->saved_raid_disk = -1;
 
 	md_update_sb(mddev, 1);
diff --git a/include/uapi/linux/raid/md_p.h b/include/uapi/linux/raid/md_p.h
index f7cf7f351144..49f4210d4394 100644
--- a/include/uapi/linux/raid/md_p.h
+++ b/include/uapi/linux/raid/md_p.h
@@ -292,6 +292,9 @@ struct mdp_superblock_1 {
 					    * backwards anyway.
 					    */
 #define	MD_FEATURE_NEW_OFFSET		64 /* new_offset must be honoured */
+#define	MD_FEATURE_RECOVERY_BITMAP	128 /* recovery that is happening
+					     * is guided by bitmap.
+					     */
 #define	MD_FEATURE_ALL			(MD_FEATURE_BITMAP_OFFSET	\
 					|MD_FEATURE_RECOVERY_OFFSET	\
 					|MD_FEATURE_RESHAPE_ACTIVE	\
@@ -299,6 +302,7 @@ struct mdp_superblock_1 {
 					|MD_FEATURE_REPLACEMENT		\
 					|MD_FEATURE_RESHAPE_BACKWARDS	\
 					|MD_FEATURE_NEW_OFFSET		\
+					|MD_FEATURE_RECOVERY_BITMAP	\
 					)
 
-#endif 
+#endif