On Mon, 25 Sep 2017 10:19:57 +0200
Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx> wrote:
> Commit 1eeef2d7483a ("mtd: handle partitioning on devices with 0
> erasesize") introduced a regression on heterogeneous erase region
> devices. Alignment of the partition was tested against the master
> eraseblock size which can be bigger than the slave one, thus leading
> to some partitions being marked as read-only.
>
> Update wr_alignment to match this slave erasesize after this erasesize
> has been determined by picking the biggest erasesize of all the regions
> embedded in the MTD partition.
>
> Reported-by: Mathias Thore <Mathias.Thore@xxxxxxxxxxxx>
> Fixes: 1eeef2d7483a ("mtd: handle partitioning on devices with 0 erasesize")
> Cc: <stable@xxxxxxxxxxxxxxx>
> Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
Applied.
> ---
> Changes in v2:
> - Fix build error reported by Mathias
> ---
> drivers/mtd/mtdpart.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
> index 5736b0c90b33..a308e707392d 100644
> --- a/drivers/mtd/mtdpart.c
> +++ b/drivers/mtd/mtdpart.c
> @@ -581,6 +581,14 @@ static struct mtd_part *allocate_partition(struct mtd_info *parent,
> slave->mtd.erasesize = parent->erasesize;
> }
>
> + /*
> + * Slave erasesize might differ from the master one if the master
> + * exposes several regions with different erasesize. Adjust
> + * wr_alignment accordingly.
> + */
> + if (!(slave->mtd.flags & MTD_NO_ERASE))
> + wr_alignment = slave->mtd.erasesize;
> +
> tmp = slave->offset;
> remainder = do_div(tmp, wr_alignment);
> if ((slave->mtd.flags & MTD_WRITEABLE) && remainder) {