dhcp: rtems_event_receive() doesn't return

[Chris Johns]

On 29/04/2014 9:13 pm, Tim Cussins wrote:
> Hi all,
>
> We use the DHCP mechanism provided by RTEMS, and have noticed a curious
> issue that manifests in long-running devices.
>
> The method 'dhcp_task' uses rtems_event_receive() with a timeout of
> 1000ms to measure time (receiving the event itself causes dhcp_task to
> exit). We're using 4.9 but with dhcp related files backported from 4.10,
> so we look like this:
>
> http://git.rtems.org/rtems/tree/cpukit/libnetworking/rtems/rtems_dhcp.c?h=4.10#n705
>
> Our problem is that the software can get into a state where
> rtems_event_receive() never returns - in a recent case, the count was
> 25287 seconds - well into the lease, but not of any particular significance.
>
> I had a network monitor interposed, recording all inbound and outbound
> traffic to the device: There is no network traffic of note at the time
> of failure.
>
> I've scanned bugzilla and the mailing list, but couldn't find a mention
> of a similar issue.
>
> Has anyone spotted behaviour like this before? The rarity of the issue
> feels like a subtle race to me - better thought would be very welcome :)
>
> FWIW: We're using the virtex bsp (ppc405).
>
> Any tips or thoughts would be much appreciated!
>

Just a simple one. Are the priorities such that it can run ? That is 
nothing else of a higher priority is running all the time.

Chris