I can confidently say that I sent another completely batshit series that will probably end up with Linus revoking any pr rights because I clearly lost it. But it was kinda tempting to see whether I could move all kthreads into nullfs and separate PID 1 from kthread filesystem state:

https://patch.msgid.link/20260303-work[email protected]

Also, usermodehelpers must cease to be a thing and so do userspace filesystem operations from kthread context.