On Thu, Jan 16, 2020 at 05:18:29PM +0100, Greg Kroah-Hartman wrote: > On Thu, Jan 16, 2020 at 05:07:05PM +0100, Johan Hovold wrote: > > USB-serial drivers must not be unbound from their ports before the > > corresponding USB driver is unbound from the parent interface so > > suppress the bind and unbind attributes. > > > > Unbinding a serial driver while it's port is open is a sure way to > > trigger a crash as any driver state is released on unbind while port > > hangup is handled on the parent USB interface level. Drivers for > > multiport devices where ports share a resource such as an interrupt > > endpoint also generally cannot handle individual ports going away. > > > > Cc: stable <stable@xxxxxxxxxxxxxxx> > > Signed-off-by: Johan Hovold <johan@xxxxxxxxxx> > > --- > > drivers/usb/serial/usb-serial.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c > > index 8f066bb55d7d..dc7a65b9ec98 100644 > > --- a/drivers/usb/serial/usb-serial.c > > +++ b/drivers/usb/serial/usb-serial.c > > @@ -1317,6 +1317,9 @@ static int usb_serial_register(struct usb_serial_driver *driver) > > return -EINVAL; > > } > > > > + /* Prevent individual ports from being unbound. */ > > + driver->driver.suppress_bind_attrs = true; > > We can still unbind the usb driver though, right? If so, this is fine > with me. Right, this is only about disabling individual ports, something which essentially no subdriver can handle while a port is open (e.g. port-data set to NULL while port is still open... boom). Johan
