Did you find an exploit on my development laptop to find what I'm working on? :) I've got the same patch sitting here locally together with a few other cleanups from before the holidays. But the problem I rant into and why I didn't finish it, is that is that the lock order doesn't work for __blk_mq_update_nr_hw_queues which freezes at a very high level and then does a queue limits update. Now the whole changing of the poll flag there look a bit questionable anyway and I was going to look into how we could fix this, probably by retiring that flag either just for blk-mq devices where the information can be derived from the tagset or entirely. I'll try to get to it ASAP.
