On Thu 01-08-19 09:31:09, David Hildenbrand wrote: > On 01.08.19 09:26, David Hildenbrand wrote: [...] > > I am not sure about the implications of having > > pfn_valid()/pfn_present()/pfn_online() return true but accessing it > > results in crashes. (suspend, kdump, whatever other technology touches > > online memory) > > (oneidea: we could of course go ahead and mark the pages PG_offline > before unmapping the pfn range to work around these issues)
PG_reserved and an elevated reference count should be enough to drive any pfn walker out. Pfn walkers shouldn't touch any page unless they know and recognize their type. -- Michal Hocko SUSE Labs
