Message-ID: <5436E0C5.3060907@hurleysoftware.com>
Date: Thu, 09 Oct 2014 15:23:49 -0400
From: Peter Hurley <peter@hurleysoftware.com>
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.1.2
MIME-Version: 1.0
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: "xinhui.pan" <xinhuix.pan@intel.com>, Jiri Slaby <jslaby@suse.cz>,
        linux-kernel@vger.kernel.org,
        "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>,
        mnipxh <mnipxh@gmail.com>, gnomes@lxorguk.ukuu.org.uk
Subject: Re: [PATCH] tty/n_gsm.c: do not clear gsm_mux entry when the gsm
 is not closed
References: <53D0CF0D.9060103@intel.com> <20140727180953.GA7232@kroah.com> <53D5F8C9.4070008@intel.com> <20140728151324.GA12973@kroah.com> <5436DB9A.6040801@hurleysoftware.com> <20141009191351.GA4256@kroah.com>
In-Reply-To: <20141009191351.GA4256@kroah.com>
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org

On 10/09/2014 03:13 PM, Greg Kroah-Hartman wrote:
> On Thu, Oct 09, 2014 at 03:01:46PM -0400, Peter Hurley wrote:
>> On 07/28/2014 11:13 AM, Greg Kroah-Hartman wrote:
>>> On Mon, Jul 28, 2014 at 03:16:25PM +0800, xinhui.pan wrote:
>>>>> Why can't you do dynamic reference counting of your structure, that
>>>>> would allow you to get rid of your global array, right?
>>>>>
>>>>
>>>> Thanks for your nice comments.
>>>> Struct gsm has a ref-count already. :)
>>>
>>> Then you should be fine, no need to keep it in an array.
>>>
>>>> And also adding a ref-count is a little hard to me. :(
>>>> This global array is used to keep tracking the gsms that stands for the gsmttyXX.
>>>
>>> You shouldn't need that at all, just use a list, you don't care what the
>>> XX number is within the driver, just allocate a new one with the next
>>> available number and you should be fine.
>>>
>>>> and it can tell us if we can create a new gsm. :)
>>>
>>> You should always be able to create a new gsm if you need to :)
>>>
>>>> In gsm_init we set *gsm_tty_driver = alloc_tty_driver(256);*
>>>
>>> Why limit to 256?  Just use a list, and a idr structure to allocate the
>>> minor number, and all should be good.
>>
>> Hi Greg,
>>
>> This is still broken in the gsm driver.
>>
>> As much as I'd like to see someone take ownership of the gsm driver and
>> do this 'the right way', I think until that happens we should consider
>> fixing the reuse-while-in-use error.
> 
> What happened to the gsm driver maintainers?

hahaha

$ ./scripts/get_maintainer.pl -f drivers/tty/n_gsm.c 
Greg Kroah-Hartman <gregkh@linuxfoundation.org> (supporter:TTY LAYER)
Jiri Slaby <jslaby@suse.cz> (supporter:TTY LAYER)
linux-kernel@vger.kernel.org (open list)

>> Would you be willing to take a patch from me that just does the bare
>> minimum to keep this from panicking in the cdev code?
> 
> Depends on what the patch looks like :)
> 
> Send it on, and I'll be glad to review it.

Ok.

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