mm: memcg: enable memcg OOM killer only for user faults
commit 519e52473ebe9db5cdef44670d5a97f1fd53d721 upstream.
System calls and kernel faults (uaccess, gup) can handle an out of memory
situation gracefully and just return -ENOMEM.
Enable the memcg OOM killer only for user faults, where it's really the
only option available.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: azurIt <azurit@pobox.sk>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index f45e21a..c0607d2 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2613,7 +2613,7 @@
return CHARGE_RETRY;
/* If we don't need to call oom-killer at el, return immediately */
- if (!oom_check)
+ if (!oom_check || !current->memcg_oom.may_oom)
return CHARGE_NOMEM;
/* check OOM */
if (!mem_cgroup_handle_oom(mem_over_limit, gfp_mask, get_order(csize)))