Linux Ethernet Bridging - Apr 2007 - [Bridge] Interface or Linux crashes when put in bridge mode

Hi all,  let me see if I can explain my problem in an explicable way.  I have
written a WLAN driver which runs on a dedicated box (e.g. not a PCMCIA card). 
The box is plugged into a client that wants WLAN connectivity via Ethernet. 
E.g.:


[        ]     Ethernet     [              ]    RF/WLAN
[ Laptop ]------------------[ WLAN adapter ]-------------
[        ]                  [              ]


For testing, I put two WLAN adapters back-to-back


[        ]     RF/WLAN      [       ]
[ WLAN-1 ]------------------[ WLAN-2]
[        ]                  [       ]


And assigned each WLAN interface and IP address (192.168.0.1 and .2).
Then I started a fast ping with a size above the WLAN MTU (for my test the MTU
was set to 500).

ping -s1000 -i0.00001 192.168.0.2 (from .1)

Everything work perfectly!

Now for the problem ...

Next I put each WLAN adapter into bridge mode, tying wlan0 to eth0 on each box. 
Note that this is now a layer-2 bridge and hence br0 has no IP address.  I
connect a laptop on each WLAN adapter:


[        ]     Eth     [        ]   RF/WLAN   [        ]     Eth     [         ]
[ Laptop ]-------------[ WLAN 1 ]-------------[ WLAN 2 ]-------------[ Laptop2 ]
[        ]             [        ]             [        ]             [         ]


And I do the same ping as above, but from laptop1 to laptop2.  Regrettably, this
causes a kernel crash (appears to be a deadlock somewhere because no oops is
output to the serial port).  It is also interesting to note that it does not
crash if the ping size is below the WLAN MTU.

So I am hoping somebody can shed some light.  I am not an expert on the Linux
bridge code, but I would assume it simply takes the data passed to one interface
and gives it to the next; so my WLAN driver should not know or care if the data
is coming from a local ping or a ping from another box, cause it should receive
the same skb, right?  I am at a total loss to explain it at this time.


Thanks for any help offered!
Adam

> So I am hoping somebody can shed some light.  I am not an expert on the
Linux bridge code, but I would assume it simply takes the data passed to one
interface and gives it to the next; so my WLAN driver should not know or care if
the data is coming from a local ping or a ping from another box, cause it should
receive the same skb, right?  I am at a total loss to explain it at this time.
> 
Sorry, won't fix your driver for you... It's open source walkthrough the
code.
You might find that your driver doesn't like it when it's transmit
routine
is called from softirq? or maybe it doesn't like spoofing the source
Ethernet
address. Use printk's or kgdb; it can't be that hard to find.