Comment 58 for bug 1832138

or if we identify the offending userspace change, then we can look at the kernel again with and try to find what bit are missing, and if we limit the kernel change then maybe the side-effect might not be present again. (assumption here)

I think the next step is really to find what userspace change started all this so we can related kernel known fix to be part of the final backport (without doing that massive 6 commits backport, which as a side-effect and who know what else).