Re: serial core: crash / race condition on unbind

From: Geert Uytterhoeven
Date: Tue Mar 11 2014 - 11:35:52 EST


Hi Peter,

On Tue, Mar 11, 2014 at 12:49 PM, Peter Hurley <peter@xxxxxxxxxxxxxxxxxx> wrote:
> On 03/11/2014 06:58 AM, Geert Uytterhoeven wrote:
>> On Tue, Mar 11, 2014 at 4:14 AM, Peter Hurley <peter@xxxxxxxxxxxxxxxxxx>
>> wrote:
>>>>
>>>>
>>>> [...]
>>>>
>>>> /*
>>>> * Indicate that there isn't a port here anymore.
>>>> */
>>>> uport->type = PORT_UNKNOWN;
>>>>
>>>> state->uart_port = NULL;
>>>
>>>
>>> How did this ever work?
>>>
>>> Detaching the ll driver from the tty port in this manner is not ok;
>>> as you already note, it blows up if consoles are still running.
>>
>> No one unbinds serial drivers using serial_core, as all these drivers are
>> for fixed hardware?
>
> Yep, never tested until now :)
> Do you need this to work?

Well, "need" may be a bit strong. Crashes are not so nice.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
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