Re: mac80211 and broadcast frames

[Valentin Manea <linux-wireless@mrs.ro>]

On 06/30/2009 07:20 PM, Luis R. Rodriguez wrote:
> On Tue, Jun 30, 2009 at 3:53 AM, Valentin Manea<linux-wireless@mrs.ro>  wrote:
>> Hi,
>>
>>    I've been working on a small project that basically sends broadcast UDP
>> frames from an Wireless AP to multiple clients. While I can send UDP frames
>> just fine from the AP to the client the only a few broadcast frames reach my
>> client. What is really puzzling is that on the client machine using tcpdump
>> I can see all the broadcast frames arriving, my application sees only a
>> small fraction of them.
>
> Keep in mind when you use tcpdump it will modify the RX filters of the
> device you use but if you say you see them on tcpdump and at the same
> time do not see them on the application that seems fishy and non
> driver related.
>
>    Luis

tcpdump doesn't affect the results at all, with or without it running 
it's the same.

I have tried tracing the packets, I thought that maybe there is a 
problem in the 80211 stack and for some reason they would be dropped but 
as far as I can tell every packet is routed to the ip stack with the 
correct protocol and pkt_type.

One more strange thing, if I'm looking at netstat -s everything seems to 
be normal, InBcastPkts is fine, also the number of incomming UDP packets.

Any ideas where I could look? it just gets stranger and stranger.


Thanks,
Valentin