Re: [Bluez-devel] Oops involving RFCOMM and sysfs

Tejun Heo
2008-01-07T08:07:55Z

Dave Young wrote:
> On Thu, Jan 03, 2008 at 02:16:21PM +0100, Gabor Gombas wrote:
>> On Wed, Jan 02, 2008 at 04:16:42PM +0100, Gabor Gombas wrote:
>>
>>> So the patch referenced above does not help. But I've found a very easy
>>> way to trigger the bug:
>>>
>>> - do a "cat /dev/zero > /dev/rfcomm0"
>>> - switch the phone off
>>> - switch the phone on, and the kernel oopses
>> FYI I also remember having oopses with 2.6.22.<something> but I do not
>> have those logs anymore. Also I now booted 2.6.20.7 and it did not oops.
>
> Could you try the patch (on 2.6.24-rc6) following and check the debug messages?
>
> diff -upr linux/net/bluetooth/rfcomm/tty.c linux.new/net/bluetooth/rfcomm/tty.c
> --- linux/net/bluetooth/rfcomm/tty.c 2008-01-04 08:58:48.000000000 +0800
> +++ linux.new/net/bluetooth/rfcomm/tty.c 2008-01-04 09:01:01.000000000 +0800
> @@ -313,6 +313,7 @@ static void rfcomm_dev_del(struct rfcomm
> {
> BT_DBG("dev %p", dev);
>
> + dump_stack();
> set_bit(RFCOMM_TTY_RELEASED, &dev->flags);
> rfcomm_dev_put(dev);
> }

Tried to reproduce the problem here but I can't persuade my laptop to
talk to my cell. :-( Gabor, can you please report what Dave Young asked?

Thanks.

--
tejun