[PATCH 3/3] nandtest: Introduce multiple reads & check iterations

[Gupta, Pekon]

>From: linux-mtd [mailto:linux-mtd-bounces at lists.infradead.org] On
>
>The current nandtest performs a simple test which consists of:
>
>  1. erase block
>  2. write data
>  3. read and verify
>
>In order to improve the nandtest strength, this commit adds a new
>parameter
>to increase the number of "read and verify" iterations. In other
>words,
>the test now consists of:
>
>  1. erase block
>  2. write data
>  3. read and verify (N times)
>
>This seem to apply more pressure on a NAND driver's ECC engine and
>has been
>used to discover stability problems with an old OMAP2.
>
If you are just re-verifying "reads", then you may be testing unstable bits [1],
which is not a valid driver's fault but a problem arising due to sudden power-cut.
If you really want to test driver then iterate all the steps (erase -> write -> read)
multiple times. Same as what is done in torture_peb() test.
	@@ drivers/mtd/ubi/io.c: torture_peb()

[1] http://www.linux-mtd.infradead.org/doc/ubifs.html#L_unstable_bits

With regards, pekon