Hi Niklas,
Thanks for your patch!
On Thu, Aug 30, 2018 at 11:39 PM Niklas Söderlund
<niklas.soderlund+renesas@xxxxxxxxxxxx> wrote:
> Fix warning when running with CONFIG_DMA_API_DEBUG_SG=y by allocating a
> device_dma_parameters structure and filling in the max segment size. The
> size used is the result of a discussion with Renesas hardware engineers
> and unfortunately not found in the datasheet.
>
> renesas_sdhi_internal_dmac ee140000.sd: DMA-API: mapping sg segment
> longer than device claims to support [len=126976] [max=65536A]
Bogus trailing "A".
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> Reported-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
>
> ---
>
> * Changes since v1
> - Use devm_kzalloc() instead of a custom remove function to clean up.
> ---
> drivers/mmc/host/renesas_sdhi_internal_dmac.c | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
> diff --git a/drivers/mmc/host/renesas_sdhi_internal_dmac.c b/drivers/mmc/host/renesas_sdhi_internal_dmac.c
> index c9dab9ce1ed55174..715e0c5dc30e4ebf 100644
> --- a/drivers/mmc/host/renesas_sdhi_internal_dmac.c
> +++ b/drivers/mmc/host/renesas_sdhi_internal_dmac.c
> @@ -308,12 +308,23 @@ static const struct soc_device_attribute gen3_soc_whitelist[] = {
> static int renesas_sdhi_internal_dmac_probe(struct platform_device *pdev)
> {
> const struct soc_device_attribute *soc = soc_device_match(gen3_soc_whitelist);
> + struct device *dev = &pdev->dev;
>
> if (!soc)
> return -ENODEV;
>
> global_flags |= (unsigned long)soc->data;
>
> + if (!dev->dma_parms) {
I guess dev->dma_parms is retained on unbind/rebind?
> + dev->dma_parms = devm_kzalloc(dev, sizeof(*dev->dma_parms),
> + GFP_KERNEL);
But by using devm_kzalloc(), the memory will be freed, and lead to reuse after
free?
> + if (!dev->dma_parms)
> + return -ENOMEM;
> + }
> +
> + if (dma_set_max_seg_size(dev, 0xffffffff))
> + dev_warn(dev, "Unable to set seg size\n");
> +
> return renesas_sdhi_probe(pdev, &renesas_sdhi_internal_dmac_dma_ops);
> }
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
