quoted

By you only addressing the deadlock as a requirement on approach a) you are
forgetting that there *may* already be present drivers which *do* implement
such patterns in the kernel. I worked on addressing the deadlock because
I was informed livepatching *did* have that issue as well and so very
likely a generic solution to the deadlock could be beneficial to other
random drivers.

In-tree zram doesn't have such deadlock, if livepatching has such AA deadlock,
just fixed it, and seems it has been fixed by 3ec24776bfd0.

I would not call it a fix. It is a kind of ugly workaround because the 
generic infrastructure lacked (lacks) the proper support in my opinion. 
Luis is trying to fix that.

Just my two cents.

Miroslav