On 17.01.20 15:42, Michal Hocko wrote: > On Fri 17-01-20 07:40:15, Qian Cai wrote: >> >> >>> On Jan 17, 2020, at 3:51 AM, David Hildenbrand <david@xxxxxxxxxx> wrote: >>> >>> -> you are accessing the pageblock without the zone lock. It could >>> change to "isolate" again in the meantime if I am not wrong! >> >> Since we are just dumping the state for debugging, it should be fine >> to accept a bit inaccuracy here due to racing. I could put a bit >> comments over there. > > Sorry, I could have been more specific. The race I was talking about is > not about accuracy. The current code is racy in that sense already > because you are looking at a struct page you do not own so its state can > change at any time. Please note that the zone->lock doesn't really The pageblock state cannot change with the zone->lock. That's what I was referring to here. (this specific check) > prevent from the state transition because that applies only to free > pages and those are obviously OK. So this is not really different. -- Thanks, David / dhildenb
