Re: [PATCH v2] usb: dwc3: set the dma max_seg_size

From: Ricardo Ribalda
Date: Fri Nov 10 2023 - 12:57:46 EST


Hi Thinh

On Wed, 1 Nov 2023 at 00:22, Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx> wrote:
>
> On Fri, Oct 27, 2023, Ricardo Ribalda wrote:
> > Allow devices to have dma operations beyond 4K, and avoid warnings such
> > as:
> >
> > DMA-API: dwc3 a600000.usb: mapping sg segment longer than device claims to support [len=86016] [max=65536]
> >
> > Cc: stable@xxxxxxxxxxxxxxx
> > Fixes: 72246da40f37 ("usb: Introduce DesignWare USB3 DRD Driver")
> > Reported-by: Zubin Mithra <zsm@xxxxxxxxxxxx>
> > Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
> > ---
> > Found while running
> > yavta -f YUYV -s 1280x720 -c /dev/video0
> >
> > with:
> >
> > CONFIG_DMA_API_DEBUG=y
> > ---
> > Changes in v2:
> > - Add stable tag
> > - Link to v1: https://urldefense.com/v3/__https://lore.kernel.org/r/20231026-dwc3-v1-1-643c74771599@chromium.org__;!!A4F2R9G_pg!b22b7Wx1QOpnFtMi7rJ0TS-rhOnMmy_sOCX3kdfln7ezNjslyMhBwHvWaXbK8D5BkKPjjn3HdID-7Ls5R3eR_4o$
> > ---
> > drivers/usb/dwc3/core.c | 2 ++
> > 1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> > index 343d2570189f..65f73dd8ef47 100644
> > --- a/drivers/usb/dwc3/core.c
> > +++ b/drivers/usb/dwc3/core.c
> > @@ -1918,6 +1918,8 @@ static int dwc3_probe(struct platform_device *pdev)
> >
> > pm_runtime_put(dev);
> >
> > + dma_set_max_seg_size(dev, UINT_MAX);
> > +
> > return 0;
> >
> > err_exit_debugfs:
> >
> > ---
> > base-commit: 611da07b89fdd53f140d7b33013f255bf0ed8f34
> > change-id: 20231026-dwc3-fac74fcb3b2a
> >
> > Best regards,
> > --
> > Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
> >
>
> Probably better to have the Closes: tag with the link to the reported
> issue. Regardless,

It was reported internally, so I have no link to share.

In this cases it seems that Reported-by with no link in good enough:
https://lore.kernel.org/all/ab557ae6-7550-189a-81dd-6e3346d84620@xxxxxxxxxxxxx/


>
> Acked-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>

Thanks!
>
> Thanks,
> Thinh



--
Ricardo Ribalda