pagemap_lru_lock things are going well. Just taking it slowly from here so bugs I may have missed don't show up in larger groups than can be effectively handled, and not feeding stuff to riel until after the issues from the last batch of things sent to him have been handled. There's an annoying one where the bugreporter has vaporized and I can't get anything close to useful info as to what happened that I'd like to get a grip on, but short of literally flying out to meet the guy, sitting on his doorstep until he reappears, and borrowing his box to debug on (which isn't going to happen) I'm not sure what can really be done.
It looks like rmap is getting close to (or at) parity on NUMA-Q now with a rollup of the pending changes so I'm slowing that down and keeping things stable. Now I'm helping to chase highmem stability issues and have some fork() efficiency issues on at a lower priority. Highmem is evil. Very evil. It's going to take a bunch of us grinding away at it full-time to make this stuff work. The niceness of direct-mapping the kernel virtual address space turns into a kva-exhaustion horror beyond imagination as dynamic:direct ratios go up. There will be much pain.