Re: [PATCH v2] fs/proc/page: Skip uninitialized page when iterating page structures

[Michal Hocko]

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.
-- 
Michal Hocko
SUSE Labs