On 11/19/18 at 09:59pm, Michal Hocko wrote: > On Mon 19-11-18 12:34:09, Hugh Dickins wrote: > > I'm glad that I delayed, what I had then (migration_waitqueue instead > > of using page_waitqueue) was not wrong, but what I've been using the > > last couple of months is rather better (and can be put to use to solve > > similar problems in collapsing pages on huge tmpfs. but we don't need > > to get into that at this time): put_and_wait_on_page_locked(). > > > > What I have not yet done is verify it on latest kernel, and research > > the interested Cc list (Linus and Tim Chen come immediately to mind), > > and write the commit comment. I have some testing to do on the latest > > kernel today, so I'll throw put_and_wait_on_page_locked() in too, > > and post tomorrow I hope. > > Cool, it seems that Baoquan has a reliable test case to trigger the > pathological case. Yes. I will test Hugh's patch.
