Re: [PATCH] serial: 8250: Reinit port_id when adding back serial8250_isa_devs

From: Andy Shevchenko
Date: Fri Aug 04 2023 - 15:44:38 EST


On Fri, Aug 04, 2023 at 03:35:44PM +0300, Tony Lindgren wrote:
> After fixing the serial core port device to use port->port_id instead of
> port->line, unloading a hardware specific 8250 port driver started
> producing an error for "sysfs: cannot create duplicate filename".
>
> This is happening as we are wrongly initializing port->port_id to zero
> when adding back serial8250_isa_devs instances, and the serial8250:0.0
> sysfs entry may already exist. For serial8250 devices, we typically have
> multiple devices mapped to a single driver instance. For the
> serial8250_isa_devs instances, the port->port_id is the same as port->line.
>
> Let's fix the issue by re-initializing port_id when adding back the
> serial8250_isa_devs instances in serial8250_unregister_port().

Good catch and fix, thank you!
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

--
With Best Regards,
Andy Shevchenko