From: Oleg Nesterov Date: Mon, 14 Mar 2011 19:05:30 +0000 (+0100) Subject: oom: oom_kill_process: fix the child_points logic X-Git-Url: https://git.karo-electronics.de/?p=mv-sheeva.git;a=commitdiff_plain;h=dc1b83ab08f1954335692cdcd499f78c94f4c42a oom: oom_kill_process: fix the child_points logic oom_kill_process() starts with victim_points == 0. This means that (most likely) any child has more points and can be killed erroneously. Also, "children has a different mm" doesn't match the reality, we should check child->mm != t->mm. This check is not exactly correct if t->mm == NULL but this doesn't really matter, oom_kill_task() will kill them anyway. Note: "Kill all processes sharing p->mm" in oom_kill_task() is wrong too. Signed-off-by: Oleg Nesterov Signed-off-by: Linus Torvalds --- diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 7dcca55ede7..b19c78eb74c 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -458,10 +458,10 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, struct mem_cgroup *mem, nodemask_t *nodemask, const char *message) { - struct task_struct *victim = p; + struct task_struct *victim; struct task_struct *child; - struct task_struct *t = p; - unsigned int victim_points = 0; + struct task_struct *t; + unsigned int victim_points; if (printk_ratelimit()) dump_header(p, gfp_mask, order, mem, nodemask); @@ -487,10 +487,15 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, * parent. This attempts to lose the minimal amount of work done while * still freeing memory. */ + victim_points = oom_badness(p, mem, nodemask, totalpages); + victim = p; + t = p; do { list_for_each_entry(child, &t->children, sibling) { unsigned int child_points; + if (child->mm == t->mm) + continue; /* * oom_badness() returns 0 if the thread is unkillable */