On Fri, Mar 10, 2023 at 03:00:39PM +0800, Zheng Wang wrote:
> In udc_plat_probe, &udc->drd_work is bound with
> udc_drd_work. udc_drd_work may be called by
> usbd_connect_notify to start the work.
>
> Besides, there is a invoking chain:
> udc_plat_probe
> ->udc_probe
> ->usb_add_gadget_udc_release
> ->usb_add_gadget
>
> It will add a new gadget to the udc class driver
> list. In usb_add_gadget, it uses usb_udc_release
> as its release function, which will kfree(udc)
> to when destroying the gadget.
>
> If we remove the module which will call udc_plat_remove
> to make cleanup, there may be a unfinished work.
> The possible sequence is as follows:
>
> Fix it by finishing the work before cleanup in the udc_plat_remove
>
> Fixes: 1b9f35adb0ff ("usb: gadget: udc: Add Synopsys UDC Platform driver")
> Signed-off-by: Zheng Wang <zyytlz.wz@xxxxxxx>
> ---
> drivers/usb/gadget/udc/snps_udc_plat.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/usb/gadget/udc/snps_udc_plat.c b/drivers/usb/gadget/udc/snps_udc_plat.c
> index 8bbb89c80348..6228e178cc0a 100644
> --- a/drivers/usb/gadget/udc/snps_udc_plat.c
> +++ b/drivers/usb/gadget/udc/snps_udc_plat.c
> @@ -230,6 +230,7 @@ static int udc_plat_remove(struct platform_device *pdev)
> struct udc *dev;
>
> dev = platform_get_drvdata(pdev);
> + cancel_delayed_work_sync(&dev->drd_work);
>
> usb_del_gadget_udc(&dev->gadget);
> /* gadget driver must not be registered */
> --
> 2.25.1
>
Please test this to verify that it actually works.
thanks,
greg k-h
