We have used also 9 months to find a perfect solution, and unfortunately, we're still in progress. That said, we release Mitaka and Newton with a known critical bug. That's fine for master branch, BUT it's not good for all the impacted stable branches. I would suggest working out a fix ASAP based on currently discussion, which maybe not perfect, but can give those cloud providers peace of mind. And put more effort on service token to get a better solution for this.
Now I'm going to repeat Erno's comments.
We have used also 9 months to find a perfect solution, and unfortunately, we're still in progress. That said, we release Mitaka and Newton with a known critical bug. That's fine for master branch, BUT it's not good for all the impacted stable branches. I would suggest working out a fix ASAP based on currently discussion, which maybe not perfect, but can give those cloud providers peace of mind. And put more effort on service token to get a better solution for this.