On Wed 10-10-18 10:39:01, Alexander Duyck wrote: > On 10/10/2018 10:24 AM, Michal Hocko wrote: [...] > > I thought I have already made it clear that these zone device hacks are > > not acceptable to the generic hotplug code. If the current reserve bit > > handling is not correct then give us a specific reason for that and we > > can start thinking about the proper fix. > > I might have misunderstood your earlier comment then. I thought you were > saying that we shouldn't bother with setting the reserved bit. Now it sounds > like you were thinking more along the lines of what I was here in my comment > where I thought the bit should be cleared later in some code specifically > related to DAX when it is exposing it for use to userspace or KVM. It seems I managed to confuse myself completely. Sorry, it's been a long day and I am sick so the brain doesn't work all that well. I will get back to this tomorrow or on Friday with a fresh brain. My recollection was that we do clear the reserved bit in move_pfn_range_to_zone and we indeed do in __init_single_page. But then we set the bit back right afterwards. This seems to be the case since d0dc12e86b319 which reorganized the code. I have to study this some more obviously. -- Michal Hocko SUSE Labs
