Comment 6 for bug 1317880

All of this is by design - image field on the instance means that the instance was started with the particular image. If the volume was created from an image at any point, and instance was booted from that volume at a later stage - it may or may not have anything to do with the image, so setting it is wrong and probably breaks a bunch of assumptions Nova code makes about the empty image field for instances booted from volume.

Luckily there is a revert for this commit that was merged by mistake here: https://review.openstack.org/#/c/107875/