On 8/28/19 10:09 AM, Michal Hocko wrote: > On Wed 28-08-19 09:46:21, Waiman Long wrote: >> On 8/28/19 4:00 AM, Michal Hocko wrote: >>> On Tue 27-08-19 16:22:38, Michal Hocko wrote: >>>> Dan, isn't this something we have discussed recently? >>> This was http://lkml.kernel.org/r/20190725023100.31141-3-t-fukasawa@xxxxxxxxxxxxx >>> and talked about /proc/kpageflags but this is essentially the same thing >>> AFAIU. I hope we get a consistent solution for both issues. >>> >> Yes, it is the same problem. The uninitialized page structure problem >> affects all the 3 /proc/kpage{cgroup,count,flags) files. >> >> Toshiki's patch seems to fix it just for /proc/kpageflags, though. > Yup. I was arguing that whacking a mole kinda fix is far from good. Dan > had some arguments on why initializing those struct pages is a problem. > The discussion had a half open end though. I hoped that Dan would try > out the initialization side but I migh have misunderstood. If the page structures of the reserved PFNs are always initialized, that will fix the problem too. I am not familiar with the zone device code. So I didn't attempt to do that. Cheers, Longman