---

yaml
---
r: 274892
b: refs/heads/master
c: 041e457
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d6137badeff1ef64b4e0092ec249ebdeaeb3ff37
+refs/heads/master: 041e4575f03400e045f00a823fcbbbb337de8409

trunk/drivers/mtd/mtdchar.c

@@ -473,6 +473,21 @@ static int mtd_do_readoob(struct mtd_info *mtd, uint64_t start,
 		ret = -EFAULT;
 
 	kfree(ops.oobbuf);
+
+	/*
+	 * NAND returns -EBADMSG on ECC errors, but it returns the OOB
+	 * data. For our userspace tools it is important to dump areas
+	 * with ECC errors!
+	 * For kernel internal usage it also might return -EUCLEAN
+	 * to signal the caller that a bitflip has occured and has
+	 * been corrected by the ECC algorithm.
+	 *
+	 * Note: most NAND ECC algorithms do not calculate ECC
+	 * for the OOB area.
+	 */
+	if (ret == -EUCLEAN || ret == -EBADMSG)
+		return 0;
+
 	return ret;
 }
 

trunk/drivers/mtd/nand/nand_base.c

@@ -1750,6 +1750,7 @@ static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
 {
 	int page, realpage, chipnr, sndcmd = 1;
 	struct nand_chip *chip = mtd->priv;
+	struct mtd_ecc_stats stats;
 	int blkcheck = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
 	int readlen = ops->ooblen;
 	int len;
@@ -1758,6 +1759,8 @@ static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
 	DEBUG(MTD_DEBUG_LEVEL3, "%s: from = 0x%08Lx, len = %i\n",
 			__func__, (unsigned long long)from, readlen);
 
+	stats = mtd->ecc_stats;
+
 	if (ops->mode == MTD_OOB_AUTO)
 		len = chip->ecc.layout->oobavail;
 	else
@@ -1828,7 +1831,11 @@ static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
 	}
 
 	ops->oobretlen = ops->ooblen;
-	return 0;
+
+	if (mtd->ecc_stats.failed - stats.failed)
+		return -EBADMSG;
+
+	return  mtd->ecc_stats.corrected - stats.corrected ? -EUCLEAN : 0;
 }
 
 /**