On Thu, Mar 16, 2023 at 11:56:45PM +0800, Zheng Wang wrote:
> In renesas_usb3_probe, &usb3->role_work is bound with
> renesas_usb3_role_work. renesas_usb3_start will be called
> to start the work.
You have a full 72 columns to write in, please use them :)
>
> If we remove the driver which will call usbhs_remove, there may be
> an unfinished work. The possible sequence is as follows:
>
> Fix it by canceling the work before cleanup in the renesas_usb3_remove.
>
> CPU0 CPU1
>
> |renesas_usb3_role_work
> renesas_usb3_remove |
> usb_role_switch_unregister |
> device_unregister |
> kfree(sw) |
> free usb3->role_sw |
> | usb_role_switch_set_role
> | //use usb3->role_sw
Why can't this be written so it looks better:
CPU0 CPU1
| renesas_usb3_role_work
renesas_usb3_remove |
usb_role_switch_unregister |
device_unregister |
kfree(sw) |
free usb3->role_sw |
| usb_role_switch_set_role
| // use usb3->role_sw
Note that removing a driver is a root-only operation, and should never
happen so please also say that.
thanks,
greg k-h
