Kernel panic on stable kernel 3.8.2 when closing bluetooth dun connection

Kernel panic on stable kernel 3.8.2 when closing bluetooth dun connection

[Sergio Callegari]

Hi,

This is just a short note to let you know that 3.8.2 panics on closing a 
bluetooth dun connection.

This is seen with the ubuntu mainline kernel 3.8.2 that should be a vanilla 
stable kernel.

Observed on a DELL E6500 which has BCM2046 Bluetooth while connecting to the
internet using a Samsung Galaxy S mobile phone via bluetooth DUN through the 
network manager.  When network manager is asked to close the connection, the 
kernel panics, the system drops out of Xorg, shows for a couple of seconds a 
long log including the words 'panic' and 'not synching', the numlock, caps-lock 
keys start flashing and the system freezes.

It is 100% repeatable.

The ubuntu kernel, that is a 3.5.0 plus ubuntu tweaks, backports, etc does not 
panic.

Thanks for the attention and best regards,

Sergio Callegari

Re: Kernel panic on stable kernel 3.8.2 when closing bluetooth dun connection

[Greg KH]

On Wed, Mar 20, 2013 at 11:18:38AM +0100, Sergio Callegari wrote:
> Hi,
> 
> This is just a short note to let you know that 3.8.2 panics on
> closing a bluetooth dun connection.

Have you notified the linux bluetooth developers about this?  Is this
new in 3.8.2 and 3.8.1 or 3.8 works fine?

thanks,

greg k-h

Re: Kernel panic on stable kernel 3.8.2 when closing bluetooth dun connection

[Sergio Callegari]

On 20/03/2013 17:17, Greg KH wrote:
> Have you notified the linux bluetooth developers about this? Is this new in 
> 3.8.2 and 3.8.1 or 3.8 works fine? thanks, greg k-h 

Hi, thanks for the advice.

I have verified that the issue was introduced with 3.8.0 and is not due to 
stabilization patches in the 3.8.x series. 3.7.x is fine (from x=0 to x=8)
Sorry for not having checked earlier, but I was incorrectly taken for granted 
that if the bug was back in 3.8.0 someone would have noticed already...
Now notifying the bluetooth developers too.

Sergio

Re: Kernel panic on stable kernel 3.8.2 when closing bluetooth dun connection

[Sergio Callegari]

In the end it may not be caused by bluetooth, but by ppp.

Found bug reports on ubuntu indicating that 3.8.x panic on ppp disconnection.
Unfortunately, I cannot try without bluetooth with my configuration.
(when wired, phone does not use ppp, but appears as a wired network interface).

Sergio