Thank you Bob!!!

It was difficult, but I successfully got access to  the UART on the device.

To speed up the failure of the device I stressed the network with a lot of 
traffic and got this output: "Buf null".
This is an output of the function wmi_event, if the allocation of an Event 
fails.

I analysed the source code and added debug messages. So I figured out that the 
buffer pool of "POOL_ID_WMI_SVC_EVENT" overflows.
This appears in function "ath_tx_status_send" and "ath_intr". The case of an 
overflow is not handled in the firmware, so it get stuck.

Do you think there is a memory leak or is my device to slow to process the 
events? What can I do to prevent this overflow?

Thanks again,
Lukas

> On Wed, Sep 23, 2015 at 11:30:04AM +0000, Lukas Göstl via Devel wrote:
> > The Mesh Network runs well for about 2 - 3 hours. Then some wireless
> > adapters get stuck and do not response anymore. They need a Powercycle
> > to work again.
> >
> > Has anybody an idea why this happens or what`s the best way to debug
> > such a problem? I don't get any output in syslog.
>
> Just the adapters but not the OS on the mesh node?  Does re-plugging the 
> device without rebooting recover?
>
> If so, it's probably a firmware or driver bug then, which are unfortunately 
> harder to debug.  One option is to get access to the UART on
> the device and then hookup a serial console, then you can at least add 
> adf_os_print() calls in the firmware to debug [1].
>
> I've seen these devices get stuck in a state where they stop sending any 
> frames at all, which you can see in debugfs on the host -- one
> of the files (can't remember the filename right now) shows available TX slots 
> and it quickly fills completely up without anything going
> over the air.  But I never root-caused this and haven't reproduced it 
> recently.
>
> [1] See http://bobcopeland.com/blog/2015/05/dwm-w034-uart/ and 
> http://bobcopeland.com/blog/2015/05/reserialized/ for two
> devices where UART access is not too hard.
>
> --
> Bob Copeland %% http://bobcopeland.com/
[Buildings under Control Symposium from October 20-21, 2015 - Register 
now!]<https://www.loytec.com/bucs>
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