While UBI and UBIFS seem to work at first sight with MLC NAND, you will most likely lose all your data upon a power-cut or due to read/write disturb. In order to protect users from bad surprises, refuse to attach to MLC NAND.
Cc: stable@vger.kernel.org Signed-off-by: Richard Weinberger richard@nod.at --- drivers/mtd/ubi/build.c | 11 +++++++++++ 1 file changed, 11 insertions(+)
diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c index e941395de3ae..753494e042d5 100644 --- a/drivers/mtd/ubi/build.c +++ b/drivers/mtd/ubi/build.c @@ -854,6 +854,17 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, return -EINVAL; }
+ /* + * Both UBI and UBIFS have been designed for SLC NAND and NOR flashes. + * MLC NAND is different and needs special care, otherwise UBI or UBIFS + * will die soon and you will lose all your data. + */ + if (mtd->type == MTD_MLCNANDFLASH) { + pr_err("ubi: refuse attaching mtd%d - MLC NAND is not supported\n", + mtd->index); + return -EINVAL; + } + if (ubi_num == UBI_DEV_NUM_AUTO) { /* Search for an empty slot in the @ubi_devices array */ for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)