Looks much better. Thanks! I am wondering whether we want to have this marked for stable. The patch is quite non-intrusive and fires only when we are really OOM. It is definitely better to try harder than go and disrupt the system by the OOM killer. So I would add Fixes: 0aaa29a56e4f ("mm, page_alloc: reserve pageblocks for high-order atomic allocations on demand") Cc: stable # 4.4+
The backport will look slightly different for kernels prior 4.6 because we do not have should_reclaim_retry yet but the check might hook right before __alloc_pages_may_oom. -- Michal Hocko SUSE Labs