On (08/03/18 13:51), Minchan Kim wrote: > > AFAIK, onging writeback page couldn't freed so it was not writeabck problem. > > What I'm tryig to fix is read part. > If we use swapcache, it shouldn't be a problem either because swapcache > has a reference count and we should wait PG_lock release before the freeing > from the swapcache so there is no race condition. Hmm, any chance a WB device can be async on its own? We add a page to a new bio and submit it to another async device driver. Then we return back to the upper layer (swap), which can free a page before the device picks up a request. Can this happen? [..] > However, I decided, at this moment, going this simple way for > stable-material to solve #0 and #1 problems at the same time. Agreed. Thanks. -ss
