recovery chooser doesn't trigger on rpi with core20

[Paul Larson]

I've been testing the core20 beta from http://cdimage.ubuntu.com/ubuntu-core/20/beta/20200512.3/ on rpi3 devices, and on all of them I've tested, I noticed that the recovery chooser comes up very inconsistently.

First, it occasionally shows up at random times for me. However I learned that you are supposed to hold down "1" at boot to enable it. I was not holding down any keys whenever I saw it come up.

However, I also tried forcing it to come up by holding the "1" key during boot. I tried multiple times on different devices, but I haven't been able to make it come up by doing that. The closest I got is one boot where nothing ever came up on the console, only a blank screen.

[Maciej Borzecki (maciek-borzecki)]

I suspect those were USB keyboard. We can explore altering the dependencies of the trigger detection services, maybe that would help, but we are basically racing against the usb stack allocating input devices and right device nodes appearing in the system.

However, I would expect the gpio-keys setup in dtb to work well. In general triggering the chooser from input devices should use a method that is most stable/reliable.