Re: [PATCH] mm: workingset: fix NULL ptr dereference

[Michal Hocko]

On Tue 10-04-18 04:56:51, Matthew Wilcox wrote:
> On Tue, Apr 10, 2018 at 11:59:03AM +0900, Minchan Kim wrote:
> > Okay, I hope this version clear current concerns.
> 
> It doesn't.  The right place to warn about GFP_ZERO used with a
> constructor is _slab_, like the patch I already sent.  We have no idea
> what other places might have the same bug, and slab is the only place
> to catch that.

I agree with that. Radix tree shouldn't be really that special. I would
rather get rid of the ctor subtle thingy but if we absolutely have to
keep it then the GFP_RECLAIM_MASK filtering and a warning in slab for
__GFP_ZERO looks like a reasonable step forward.
-- 
Michal Hocko
SUSE Labs