| Message ID | 20230804123546.25293-1-tony@atomide.com |
|---|---|
| State | New |
| Headers | show |
| Series | serial: 8250: Reinit port_id when adding back serial8250_isa_devs | expand |
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@linux.intel.com>
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -1204,6 +1204,7 @@ void serial8250_unregister_port(int line) uart->port.flags &= ~UPF_BOOT_AUTOCONF; uart->port.type = PORT_UNKNOWN; uart->port.dev = &serial8250_isa_devs->dev; + uart->port.port_id = line; uart->capabilities = 0; serial8250_init_port(uart); serial8250_apply_quirks(uart);
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(). Fixes: d962de6ae51f ("serial: core: Fix serial core port id to not use port->line") Signed-off-by: Tony Lindgren <tony@atomide.com> --- drivers/tty/serial/8250/8250_core.c | 1 + 1 file changed, 1 insertion(+)