From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Hurley <peter@hurleysoftware.com>
Date: Tue, 11 Mar 2014 11:49:56 +0000
Subject: Re: serial core: crash / race condition on unbind
Message-Id: <531EF864.5020104@hurleysoftware.com>
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To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, linux-serial@vger.kernel.org, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, Linux-sh list <linux-sh@vger.kernel.org>, One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>

On 03/11/2014 06:58 AM, Geert Uytterhoeven wrote:
> Hi Peter,
>
> On Tue, Mar 11, 2014 at 4:14 AM, Peter Hurley <peter@hurleysoftware.com> 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?

> Hot-pluggable usb-serial doesn't use serial_core.

I guess none of the 8250 PCI adapters are hot-pluggable...

Regards,
Peter Hurley