From 5aecc85abdb9ac2b0e6548d13652a34142e7ae89 Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Tue, 15 Nov 2011 14:36:07 -0800 Subject: [PATCH] oom: do not kill tasks with oom_score_adj OOM_SCORE_ADJ_MIN Commit c9f01245 ("oom: remove oom_disable_count") has removed the oom_disable_count counter which has been used for early break out from oom_badness so we could never select a task with oom_score_adj set to OOM_SCORE_ADJ_MIN (oom disabled). Now that the counter is gone we are always going through heuristics calculation and we always return a non zero positive value. This means that we can end up killing a task with OOM disabled because it is indistinguishable from regular tasks with 1% resp. CAP_SYS_ADMIN tasks with 3% usage of memory or tasks with oom_score_adj set but OOM enabled. Let's break out early if the task should have OOM disabled. Signed-off-by: Michal Hocko Acked-by: David Rientjes Acked-by: KOSAKI Motohiro Cc: Oleg Nesterov Cc: Ying Han Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/oom_kill.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 471dedb463ab..76f2c5ae908e 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -185,6 +185,11 @@ unsigned int oom_badness(struct task_struct *p, struct mem_cgroup *mem, if (!p) return 0; + if (p->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) { + task_unlock(p); + return 0; + } + /* * The memory controller may have a limit of 0 bytes, so avoid a divide * by zero, if necessary. -- 2.20.1