On Thu, 15 Dec 2011 13:36:11 -0800 (PST) David Rientjes <rientjes@xxxxxxxxxx> wrote: > The oom killer relies on logic that identifies threads that have already > been oom killed when scanning the tasklist and, if found, deferring until > such threads have exited. This is done by checking for any candidate > threads that have the TIF_MEMDIE bit set. > > For memcg ooms, candidate threads are first found by calling > task_in_mem_cgroup() since the oom killer should not defer if there's an > oom killed thread in another memcg. > > Unfortunately, task_in_mem_cgroup() excludes threads if they have > detached their mm in the process of exiting so TIF_MEMDIE is never > detected for such conditions. This is different for global, mempolicy, > and cpuset oom conditions where a detached mm is only excluded after > checking for TIF_MEMDIE and deferring, if necessary, in > select_bad_process(). > > The fix is to return true if a task has a detached mm but is still in the > memcg or its hierarchy that is currently oom. This will allow the oom > killer to appropriately defer rather than kill unnecessarily or, in the > worst case, panic the machine if nothing else is available to kill. > > Acked-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> > Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx> Thank you. Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>