• Nikita Kiryanov's avatar
    mtd: nand: omap: fix sw->hw->sw ecc switch · eb237a15
    Nikita Kiryanov authored
    
    
    When switching ecc mode, omap_select_ecc_scheme() assigns the appropriate values
    into the current nand chip's ecc.layout struct. This is done under the
    assumption that the struct exists only to store values, so it is OK to overwrite
    it, but there is at least one situation where this assumption is incorrect:
    
    When switching to 1 bit hamming code sw ecc, the job of assigning layout data
    is outsourced to nand_scan_tail(), which simply assigns into ecc.layout a
    pointer to an existing struct prefilled with the appropriate values. This struct
    doubles as both data and layout definition, and therefore shouldn't be
    overwritten, but on the next switch to hardware ecc, this is exactly what's
    going to happen. The next time the user switches to software ecc, they're
    going to get a messed up ecc layout.
    
    Prevent this and possible similar bugs by explicitly using the
    private-to-omap_gpmc.c omap_ecclayout struct when switching ecc mode.
    
    Cc: Scott Wood <scottwood@freescale.com>
    Cc: Pekon Gupta <pekon@ti.com>
    Signed-off-by: default avatarNikita Kiryanov <nikita@compulab.co.il>
    eb237a15
omap_gpmc.c 28.8 KB