Comment 7 for bug 1436427

@Michael

Thanks for the feedback.

I'd like keep this bug specifically for the problem that occurs when WiFi is toggled off ( as per the bug description and summary ). The problem when going out of range of the access point may be something completely different, and is being addressed in bug #1410113.

Also, problems with the location service while related, should be considered separate too.

Regarding the toggle WiFi problem, I created a stress test to try and reproduce the problem, while I will have reviewed on Monday, to ensure that I didn't get anything wrong. The WiFi toggle switch, contrary to my original understanding, doesn't toggle the urfkill switch directly, instead, it toggles the value of the global NetworkManager property 'WirelessEnabled'. NM in turn will enable/disable WiFi via urfkill, which in turn on krillin uses hybris to load/unload the WiFi driver.

I believe the problem we hit when WiFi is disabled, and the routing table is empty, is caused by a race between rild and NetworkManager, however until I can reproduce, it's just that... a theory.

As mentioned, I was able to reproduce this once two days ago, but haven't managed to reproduce it since. I've run 500 iterations of enable/disable WiFi using my stress test, and haven't yet hit the issue. This is why I reduced the Importance of *this* scenario to High. The out-of-range problem will now be my priority.

Finally, one other bug that may compound this problem is a long-standing issue with the network indicator which shows extreme latency sometimes displaying the correct network connection to the user. So even though the indicator may show that you have a mobile data connection, it may not actually be showing the true state of things. See bug #1339792 for more details. There's a concerted effort to fix issues with the indicator; ubuntu silo-6 contains a new version which hopefully will improve this situation.