Re: [REGRESSION] Bluetooth adapter provided by `btusb` not recognized since v6.13.2

[Doug Anderson]

Hi,

On Wed, Nov 19, 2025 at 4:43 PM <incogcyberpunk@xxxxxxxxx> wrote:
>
> Yes, manually updating `drivers/btusb/btusb.c` , with the below proposed patch fixes the regression issue.
> The proposed patch solves the regression of `bluetooth adapter provided by btusb not being recognized in both the stable and the mainline kernel since 6.13.2`
>
> The proposed patch:
> `
> index a722446ec73d..1466e0f1865d 100644
> --- a/drivers/bluetooth/btusb.c
> +++ b/drivers/bluetooth/btusb.c
> @@ -2714,6 +2714,11 @@ static void btusb_mtk_claim_iso_intf(struct btusb_data *data)
>         struct btmtk_data *btmtk_data = hci_get_priv(data->hdev);
>         int err;
>
> +       if (!btmtk_data->isopkt_intf) {
> +               bt_dev_err(data->hdev, "Can't claim NULL iso interface");
> +               return;
> +       }
> +
>         /*
>          * The function usb_driver_claim_interface() is documented to need
>          * locks held if it's not called from a probe routine. The code here
> `
>
> I applied the patch as suggested, but now what do I have to do to get this fixed upstream and fixed in the next mainline & stable releases.

Excellent. The best way to get the fix landed is to respond to the
post I made at:

https://lore.kernel.org/r/20251119085354.1.I1ae7aebc967e52c7c4be7aa65fbd81736649568a@changeid

...and add your "Tested-by" tag. With that, the Bluetooth maintainers
(if they're happy with the patch) will land it and it can start
working its way to stable.


> Also, could you brief a bit, on how this proposed patch containing , a NULL check for the `btmtk_data->isopkt_intf`; solves the problems introduced by the problematic commit with: [ Upstream commit e9087e828827e5a5c85e124ce77503f2b81c3491 ]

Check out the commit message on the patch I posted. I explained why
the NULL check fixes the problem there. If that's unclear, I can try
rewording.


-Doug