Re: mm, vmscan: commit makes PAE kernel crash nightly (bisected)

From: Michal Hocko
Date: Tue Jan 24 2017 - 07:59:57 EST

On Mon 23-01-17 10:48:58, Mel Gorman wrote:
> Unfortunately, even that will be race prone for GFP_NOFS callers as
> they'll effectively be racing to see if kswapd or another direct
> reclaimer can reclaim before the OOM conditions are hit. It is by
> design, but it's apparent that a __GFP_NOFAIL request can trigger OOM
> relatively easily as it's not necessarily throttled or waiting on kswapd
> to complete any work. I'll keep thinking about it.

Yes, we shouldn't trigger the OOM for GFP_NOFS as the memory reclaim is
really weaker. And that might really matter here. So the mmomt tree will
behave differently in this regards as we have [1]

Michal Hocko