Comment 9 for bug 1961079

This is very unfortunate. So the UEFI system is able to read mdraid 1.2 too, and can access ESPs inside of it?

Most systems do not implement linux's mdraid in their firmware, and hence putting the ESP inside the RAID would lead to unbootable systems; which is why we designed the solution where you can place an ESP on each disk outside the raid and then raid the partitions instead.

There's some caveats in that systems accidentally can read ESPs in an mdraid 1.0 as the metadata is at the end only, but in general exposing that would be a bad idea.

So I guess one could implement a quirk to allow you to place ESPs in there on this specific hardware, but creating such RAIDs and placing ESPs in them in general should not be possible.