Re: [Kgdb-bugreport] [PATCH 4/5] KGDB-8250: refactor configuration

From: Jan Kiszka
Date: Fri Feb 01 2008 - 16:11:02 EST


Sergei Shtylyov wrote:
> Hello.
>
> Jan Kiszka wrote:
>
>> Sorry, previous version was missing some __init[data] attributes which
>> were dropped in an intermediate stage. Here comes an updated patch:
>
>> <---snip--->
>
>> This major refactoring of the quite complex kgdb8250 configuration does
>> the following:
>
>> - ensures that static configurations according to SERIAL_PORT_DFNS are
>> always loaded first
>> - tries to pull more accurate configuration via serial8250_get_port_def
>> if simple-config is used
>> - detects empty/invalid simple-configs
>> - enforces KGDB_PORT_NUM <= SERIAL_8250_NR_UARTS at kconfig level
>> - removes kgdb8250_add_port and its hook in serial_core (calling
>> serial8250_get_port_def in demand should provide us the same
>> information)
>
> You left powerpc-lite.patch broken with this change as it has
> multiple calls to kgdb8250_add_port()...

I see. But I wonder if there ever was a real need for these hooks (in
2.4 times?): If I look at bamboo_early_serial_map() e.g., I find it
calling into early_serial_setup() which fills serial8250_ports[] - and
that content is now retrieved via serial8250_get_port_def() when we
parse the runtime or build-time provided parameters (port number &
baudrate).

>
>> Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxx>
>
>> Index: b/drivers/serial/serial_core.c
>> ===================================================================
>> --- a/drivers/serial/serial_core.c
>> +++ b/drivers/serial/serial_core.c
> [...]
>> @@ -2370,12 +2369,6 @@ int uart_add_one_port(struct uart_driver
>> */
>> port->flags &= ~UPF_DEAD;
>>
>> -#if defined(CONFIG_KGDB_8250)
>> - /* Add any 8250-like ports we find later. */
>> - if (port->type <= PORT_MAX_8250)
>> - kgdb8250_add_port(port->line, port);
>> -#endif
>> -
>
> I'm afraid this wasn't correct from the very start since this can add
> ports with .iotype that 8250_kgdb.c does not support. So, nothing to
> regret here...

I think a lot of cruft piled up in the kgdb patches over their long life. :)

Thanks for your feedback!

Jan
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/