diff --git a/ext4_utils/Android.mk b/ext4_utils/Android.mk
index 1fef735..6eba3b1 100644
--- a/ext4_utils/Android.mk
+++ b/ext4_utils/Android.mk
@@ -12,7 +12,8 @@
     indirect.c \
     uuid.c \
     sha1.c \
-    wipe.c
+    wipe.c \
+    crc16.c
 
 #
 # -- All host/targets including windows
diff --git a/ext4_utils/allocate.c b/ext4_utils/allocate.c
index adf91ba..3229abe 100644
--- a/ext4_utils/allocate.c
+++ b/ext4_utils/allocate.c
@@ -56,6 +56,7 @@
 	u32 first_free_block;
 	u32 free_inodes;
 	u32 first_free_inode;
+	u16 flags;
 	u16 used_dirs;
 };
 
@@ -157,24 +158,8 @@
 
 	sparse_file_add_data(info.sparse_file, bg->inode_table,
 			aux_info.inode_table_blocks	* info.block_size, block);
-}
 
-void init_unused_inode_tables(void)
-{
-	unsigned int i;
-	u32 block;
-	struct block_group_info *bg;
-
-	for (i = 0; i < aux_info.groups; i++) {
-		if (!aux_info.bgs[i].inode_table) {
-			bg = &aux_info.bgs[i];
-			block = bg->first_block + 2;
-			if (bg->has_superblock)
-				block += aux_info.bg_desc_blocks + info.bg_desc_reserve_blocks + 1;
-			sparse_file_add_fill(info.sparse_file, 0,
-					aux_info.inode_table_blocks * info.block_size, block);
-		}
-	}
+	bg->flags &= ~EXT4_BG_INODE_UNINIT;
 }
 
 static int bitmap_set_bit(u8 *bitmap, u32 bit)
@@ -297,6 +282,7 @@
 	bg->first_free_block = 0;
 	bg->free_inodes = info.inodes_per_group;
 	bg->first_free_inode = 1;
+	bg->flags = EXT4_BG_INODE_UNINIT;
 
 	if (reserve_blocks(bg, bg->first_free_block, bg->header_blocks) < 0)
 		error("failed to reserve %u blocks in block group %u\n", bg->header_blocks, i);
@@ -744,6 +730,12 @@
 	return aux_info.bgs[bg].used_dirs;
 }
 
+/* Returns the flags for a block group */
+u16 get_bg_flags(int bg)
+{
+	return aux_info.bgs[bg].flags;
+}
+
 /* Frees the memory used by a linked list of allocation regions */
 void free_alloc(struct block_allocation *alloc)
 {
diff --git a/ext4_utils/allocate.h b/ext4_utils/allocate.h
index fb6e0f7..0575e84 100644
--- a/ext4_utils/allocate.h
+++ b/ext4_utils/allocate.h
@@ -41,6 +41,7 @@
 u32 reserve_inodes(int bg, u32 inodes);
 void add_directory(u32 inode);
 u16 get_directories(int bg);
+u16 get_bg_flags(int bg);
 void init_unused_inode_tables(void);
 u32 allocate_inode();
 void free_alloc(struct block_allocation *alloc);
diff --git a/ext4_utils/crc16.c b/ext4_utils/crc16.c
new file mode 100644
index 0000000..2575812
--- /dev/null
+++ b/ext4_utils/crc16.c
@@ -0,0 +1,58 @@
+/*-
+ *  COPYRIGHT (C) 1986 Gary S. Brown.  You may use this program, or
+ *  code or tables extracted from it, as desired without restriction.
+ */
+
+/* CRC32 code derived from work by Gary S. Brown. */
+
+/* Code taken from FreeBSD 8 */
+
+/* Converted to crc16 */
+
+#include "ext4_utils.h"
+
+static u16 crc16_tab[] = {
+		0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241,
+		0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440,
+		0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40,
+		0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841,
+		0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40,
+		0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41,
+		0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641,
+		0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040,
+		0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240,
+		0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441,
+		0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41,
+		0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840,
+		0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41,
+		0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40,
+		0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640,
+		0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041,
+		0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240,
+		0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441,
+		0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41,
+		0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840,
+		0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41,
+		0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40,
+		0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640,
+		0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041,
+		0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241,
+		0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440,
+		0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40,
+		0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841,
+		0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40,
+		0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41,
+		0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641,
+		0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040,
+};
+
+u16 ext4_crc16(u16 crc_in, const void *buf, int size)
+{
+        const u8 *p = buf;
+        u16 crc = crc_in;
+
+        while (size--)
+                crc = crc16_tab[(crc ^ *p++) & 0xFF] ^ (crc >> 8);
+
+        return crc;
+}
diff --git a/ext4_utils/ext4_utils.c b/ext4_utils/ext4_utils.c
index 43b4480..4b87c6e 100644
--- a/ext4_utils/ext4_utils.c
+++ b/ext4_utils/ext4_utils.c
@@ -25,6 +25,7 @@
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <sys/types.h>
+#include <stddef.h>
 #include <string.h>
 
 #ifdef USE_MINGW
@@ -362,11 +363,12 @@
    block group */
 void ext4_update_free()
 {
-	unsigned int i;
+	u32 i;
 
 	for (i = 0; i < aux_info.groups; i++) {
 		u32 bg_free_blocks = get_free_blocks(i);
 		u32 bg_free_inodes = get_free_inodes(i);
+		u16 crc;
 
 		aux_info.bg_desc[i].bg_free_blocks_count = bg_free_blocks;
 		aux_info.sb->s_free_blocks_count_lo += bg_free_blocks;
@@ -375,6 +377,13 @@
 		aux_info.sb->s_free_inodes_count += bg_free_inodes;
 
 		aux_info.bg_desc[i].bg_used_dirs_count += get_directories(i);
+
+		aux_info.bg_desc[i].bg_flags = get_bg_flags(i);
+
+		crc = ext4_crc16(~0, aux_info.sb->s_uuid, sizeof(aux_info.sb->s_uuid));
+		crc = ext4_crc16(crc, &i, sizeof(i));
+		crc = ext4_crc16(crc, &aux_info.bg_desc[i], offsetof(struct ext2_group_desc, bg_checksum));
+		aux_info.bg_desc[i].bg_checksum = crc;
 	}
 }
 
diff --git a/ext4_utils/ext4_utils.h b/ext4_utils/ext4_utils.h
index 26952c0..0d0b6bc 100644
--- a/ext4_utils/ext4_utils.h
+++ b/ext4_utils/ext4_utils.h
@@ -99,8 +99,10 @@
 	__le16 bg_free_blocks_count;
 	__le16 bg_free_inodes_count;
 	__le16 bg_used_dirs_count;
-	__le16 bg_pad;
-	__le32 bg_reserved[3];
+	__le16 bg_flags;
+	__le32 bg_reserved[2];
+	__le16 bg_reserved16;
+	__le16 bg_checksum;
 };
 
 struct fs_info {
@@ -166,6 +168,7 @@
 u64 get_file_size(int fd);
 u64 parse_num(const char *arg);
 void ext4_parse_sb(struct ext4_super_block *sb);
+u16 ext4_crc16(u16 crc_in, const void *buf, int size);
 
 typedef void (*fs_config_func_t)(const char *path, int dir, unsigned *uid, unsigned *gid,
         unsigned *mode);
@@ -174,7 +177,7 @@
 
 int make_ext4fs_internal(int fd, const char *directory,
                          const char *mountpoint, fs_config_func_t fs_config_func, int gzip,
-                         int sparse, int crc, int wipe, int init_itabs,
+                         int sparse, int crc, int wipe,
                          struct selabel_handle *sehnd, int verbose);
 
 #ifdef __cplusplus
diff --git a/ext4_utils/make_ext4fs.c b/ext4_utils/make_ext4fs.c
index f62fee9..b2d1426 100644
--- a/ext4_utils/make_ext4fs.c
+++ b/ext4_utils/make_ext4fs.c
@@ -361,7 +361,7 @@
 	reset_ext4fs_info();
 	info.len = len;
 
-	return make_ext4fs_internal(fd, NULL, mountpoint, NULL, 0, 1, 0, 0, 0, sehnd, 0);
+	return make_ext4fs_internal(fd, NULL, mountpoint, NULL, 0, 1, 0, 0, sehnd, 0);
 }
 
 int make_ext4fs(const char *filename, long long len,
@@ -379,7 +379,7 @@
 		return EXIT_FAILURE;
 	}
 
-	status = make_ext4fs_internal(fd, NULL, mountpoint, NULL, 0, 0, 0, 1, 0, sehnd, 0);
+	status = make_ext4fs_internal(fd, NULL, mountpoint, NULL, 0, 0, 0, 1, sehnd, 0);
 	close(fd);
 
 	return status;
@@ -444,7 +444,7 @@
 
 int make_ext4fs_internal(int fd, const char *_directory,
                          const char *_mountpoint, fs_config_func_t fs_config_func, int gzip,
-                         int sparse, int crc, int wipe, int init_itabs,
+                         int sparse, int crc, int wipe,
                          struct selabel_handle *sehnd, int verbose)
 {
 	u32 root_inode_num;
@@ -507,7 +507,8 @@
 
 	info.feat_ro_compat |=
 			EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER |
-			EXT4_FEATURE_RO_COMPAT_LARGE_FILE;
+			EXT4_FEATURE_RO_COMPAT_LARGE_FILE |
+			EXT4_FEATURE_RO_COMPAT_GDT_CSUM;
 
 	info.feat_incompat |=
 			EXT4_FEATURE_INCOMPAT_EXTENTS |
@@ -580,9 +581,6 @@
 
 	ext4_update_free();
 
-	if (init_itabs)
-		init_unused_inode_tables();
-
 	ext4_queue_sb();
 
 	printf("Created filesystem with %d/%d inodes and %d/%d blocks\n",
diff --git a/ext4_utils/make_ext4fs_main.c b/ext4_utils/make_ext4fs_main.c
index 739c4a1..b6c740d 100644
--- a/ext4_utils/make_ext4fs_main.c
+++ b/ext4_utils/make_ext4fs_main.c
@@ -53,7 +53,7 @@
 	fprintf(stderr, "    [ -g <blocks per group> ] [ -i <inodes> ] [ -I <inode size> ]\n");
 	fprintf(stderr, "    [ -L <label> ] [ -f ] [ -a <android mountpoint> ]\n");
 	fprintf(stderr, "    [ -S file_contexts ]\n");
-	fprintf(stderr, "    [ -z | -s ] [ -t ] [ -w ] [ -c ] [ -J ] [ -v ]\n");
+	fprintf(stderr, "    [ -z | -s ] [ -w ] [ -c ] [ -J ] [ -v ]\n");
 	fprintf(stderr, "    <filename> [<directory>]\n");
 }
 
@@ -68,7 +68,6 @@
 	int sparse = 0;
 	int crc = 0;
 	int wipe = 0;
-	int init_itabs = 0;
 	int fd;
 	int exitcode;
 	int verbose = 0;
@@ -129,7 +128,7 @@
 			sparse = 1;
 			break;
 		case 't':
-			init_itabs = 1;
+			fprintf(stderr, "Warning: -t (initialize inode tables) is deprecated\n");
 			break;
 		case 'S':
 #ifndef USE_MINGW
@@ -202,7 +201,7 @@
 	}
 
 	exitcode = make_ext4fs_internal(fd, directory, mountpoint, fs_config_func, gzip,
-			sparse, crc, wipe, init_itabs, sehnd, verbose);
+			sparse, crc, wipe, sehnd, verbose);
 	close(fd);
 
 	return exitcode;