subiquity/curtin refuse to install into existing partitions

[Kai Harrekilde-Petersen]

With Ubuntu 20.05.2, after fixing https://bugs.launchpad.net/bugs/1878890, the subiquity/curtin installer won't install into a set of existing partitions.

With the following partition table, subiquity/curtin refuses to use /dev/sda1 as boot partition and /dev/sda3 as root partition - something it previously accepted as choices (but it failed during the process).

{
   "partitiontable": {
      "label":"dos",
      "id":"0xd9859edb",
      "device":"/dev/sda",
      "unit":"sectors",
      "partitions": [
         {"node":"/dev/sda1", "start":2048, "size":1998047, "type":"83", "bootable":true},
         {"node":"/dev/sda2", "start":2000896, "size":2000896, "type":"83"},
         {"node":"/dev/sda3", "start":4001792, "size":64000000, "type":"83"}
      ]
   }

[Michael Hudson-Doyle (mwhudson)]

Hi, the fix for that bug hasn't been released yet. It is in edge now but wasn't when you filed the bug. If you can test the version from edge, that would be great. Instructions on this at https://ubu.one/test-edge-subiquity