@Ken

So although we have a pending fix that's been merged in our ofono trunk,
I still would like to better understand what caused the crash during
autopilot testing.

The fix removes an assert in the ril device plugin when the radio state
becomes UNAVAILABLE and the plugin's online flag is TRUE.  Essentially
this assert is  saying, if the radio ever goes OFF/UNAVAILABLE by itself
without instruction from ofono, this is something that can't be
handled...  so assert, upstart restarts ofono, and in theory the system
recovers.

That said, we never really thought thru what happens during system
shutdown.  As ofono is never told the system is shutting down, then
whenever the container shuts down rild, it triggers the radio
unavailable scenario and the assert happens, which could potentially
lead to more than one crash/restart.

NOTE - with the proposed fix, UNAVAILABLE state transitions are
*ignored*, however if OFF occurs instead, the same assert will still
fire.

Can you or someone from your team isolate the AP test case that causes
the failure?  FlightMode shouldn't trigger this error as urfkill tells
ofono to go offline, which triggers a RADIO POWER OFF message to rild.
This sequence results in the plugin's online flag being set to FALSE
*before* the radio power message is sent, so in theory, the assert
should never happen.

If we have other non-shutdown scenarios that trigger the radio
UNAVAILABLE state, ignoring the state may not be the wisest course of
action.

Perhaps it's worth changing the assert to a graceful exit, returing a
non-success error code, which would still allow upstart to restart
ofono, but would no longer leave .crash files laying around.

Finally, we might also want to consider whether additional shutdown
logic for ofono, urfkill, and other components in the
networking/telephony stack is required.  Note, there may be hooks and/or
logic for shutdown in some of these components, however the timing might
not be properly synced with the container shutdown.

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https://bugs.launchpad.net/bugs/1490991

Title:
  ofono hitting an assert during settings test

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