Re: [PATCH] mmc: mmci: stm32: fix max busy timeout calculation

[Ulf Hansson]

On Tue, 13 Jun 2023 at 15:42, Yann Gautier <yann.gautier@xxxxxxxxxxx> wrote:
>
> From: Christophe Kerello <christophe.kerello@xxxxxxxxxxx>
>
> The way that the timeout is currently calculated could lead to a u64
> timeout value in mmci_start_command(). This value is then cast in a u32
> register that leads to mmc erase failed issue with some SD cards.
>
> Fixes: 8266c585f489 ("mmc: mmci: add hardware busy timeout feature")
> Signed-off-by: Yann Gautier <yann.gautier@xxxxxxxxxxx>
> Signed-off-by: Christophe Kerello <christophe.kerello@xxxxxxxxxxx>

Applied for fixes and by adding a stable tag, thanks!

Kind regards
Uffe

> ---
>  drivers/mmc/host/mmci.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
> index f2b2e8b0574e8..696cbef3ff7de 100644
> --- a/drivers/mmc/host/mmci.c
> +++ b/drivers/mmc/host/mmci.c
> @@ -1735,7 +1735,8 @@ static void mmci_set_max_busy_timeout(struct mmc_host *mmc)
>                 return;
>
>         if (host->variant->busy_timeout && mmc->actual_clock)
> -               max_busy_timeout = ~0UL / (mmc->actual_clock / MSEC_PER_SEC);
> +               max_busy_timeout = U32_MAX / DIV_ROUND_UP(mmc->actual_clock,
> +                                                         MSEC_PER_SEC);
>
>         mmc->max_busy_timeout = max_busy_timeout;
>  }
> --
> 2.25.1
>