Hi,
> From: Zheng Wang, Sent: Thursday, April 13, 2023 4:49 PM
>
> In usbhs_probe, &priv->notify_hotplug_work is bound with
> usbhsc_notify_hotplug. It will be started then.
>
> If we remove the driver which will call usbhs_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 usbhs_remove
>
> CPU0 CPU1
>
> |usbhsc_notify_hotplug
> usbhs_remove |
> usbhs_mod_remove |
> usbhs_mod_gadget_remove|
> kfree(gpriv); |
> |usbhsc_hotplug
> |usbhs_mod_call start
> |usbhsg_start
> |usbhsg_try_start
> |//use gpriv
Thank you for the patch!
You should adjust the figure like followings because Greg mentioned it on other patch [1].
-----
CPU0 CPU1
| usbhsc_notify_hotplug
usbhs_remove |
usbhs_mod_remove |
usbhs_mod_gadget_remove |
kfree(gpriv); |
| usbhsc_hotplug
| usbhs_mod_call start
| usbhsg_start
| usbhsg_try_start
| //use gpriv
-----
[1]
https://lore.kernel.org/lkml/ZBNCam0XjWehrF3c@xxxxxxxxx/
Best regards,
Yoshihiro Shimoda
> Fixes: bc57381e6347 ("usb: renesas_usbhs: use delayed_work instead of work_struct")
> Signed-off-by: Zheng Wang <zyytlz.wz@xxxxxxx>
> ---
> drivers/usb/renesas_usbhs/common.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/usb/renesas_usbhs/common.c b/drivers/usb/renesas_usbhs/common.c
> index 96f3939a65e2..17a0987ef4f5 100644
> --- a/drivers/usb/renesas_usbhs/common.c
> +++ b/drivers/usb/renesas_usbhs/common.c
> @@ -768,6 +768,7 @@ static int usbhs_remove(struct platform_device *pdev)
>
> dev_dbg(&pdev->dev, "usb remove\n");
>
> + cancel_delayed_work_sync(&priv->notify_hotplug_work);
> /* power off */
> if (!usbhs_get_dparam(priv, runtime_pwctrl))
> usbhsc_power_ctrl(priv, 0);
> --
> 2.25.1
