diff --git a/cmd/Kconfig b/cmd/Kconfig
index c414c5d..0eca0f7 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -1986,6 +1986,14 @@
 	  at least as large as the size specified in the mtdparts variable and
 	  2) each partition starts on a good block.
 
+config CMD_MTDPARTS_SHOW_NET_SIZES
+	bool "Show net size (w/o bad blocks) of partitions"
+	depends on CMD_MTDPARTS
+	help
+	  Adds two columns to the printed partition table showing the
+	  effective usable size of a partition, if bad blocks are taken
+	  into account.
+
 config CMD_REISER
 	bool "reiser - Access to reiserfs filesystems"
 	help
diff --git a/cmd/mtdparts.c b/cmd/mtdparts.c
index 46155ca..b40c2af 100644
--- a/cmd/mtdparts.c
+++ b/cmd/mtdparts.c
@@ -1233,11 +1233,11 @@
 {
 	uint64_t i, net_size = 0;
 
-	if (!mtd->block_isbad)
+	if (!mtd->_block_isbad)
 		return part->size;
 
 	for (i = 0; i < part->size; i += mtd->erasesize) {
-		if (!mtd->block_isbad(mtd, part->offset + i))
+		if (!mtd->_block_isbad(mtd, part->offset + i))
 			net_size += mtd->erasesize;
 	}
 
@@ -1274,7 +1274,7 @@
 			part = list_entry(pentry, struct part_info, link);
 			net_size = net_part_size(mtd, part);
 			size_note = part->size == net_size ? " " : " (!)";
-			printf("%2d: %-20s0x%08x\t0x%08x%s\t0x%08x\t%d\n",
+			printf("%2d: %-20s0x%08llx\t0x%08x%s\t0x%08llx\t%d\n",
 					part_num, part->name, part->size,
 					net_size, size_note, part->offset,
 					part->mask_flags);