On Wed, Nov 2, 2022 at 3:31 PM Gerald Schaefer <gerald.schaefer@xxxxxxxxxxxxx> wrote: > > Just wondering a bit why you did not also add the > VM_WARN_ON_ONCE_PAGE(page_mapcount(page) < 0, page), like > in the generic change. Heh, I had considered dropping it entirely even from the generic code, since I don't remember seeing that ever trigger, but PeterZ convinced me otherwise. For the s390 side I really wanted to keep things minimal since I (obviously) didn't even built-test it, so.. I'm perfectly happy with s390 people adding it later, of course. Linus