>From 22bd036766e70f0df38c38f3ecc226e857d20faf Mon Sep 17 00:00:00 2001 From: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> Date: Wed, 17 Feb 2016 16:30:59 +0900 Subject: [PATCH 2/6] mm,oom: don't abort on exiting processes when selecting a victim. Currently, oom_scan_process_thread() returns OOM_SCAN_ABORT when there is a thread which is exiting. But it is possible that that thread is blocked at down_read(&mm->mmap_sem) in exit_mm() called from do_exit() whereas one of threads sharing that memory is doing a GFP_KERNEL allocation between down_write(&mm->mmap_sem) and up_write(&mm->mmap_sem) (e.g. mmap()). Under such situation, the OOM killer does not choose a victim, which results in silent OOM livelock problem. This patch changes oom_scan_process_thread() not to return OOM_SCAN_ABORT when there is a thread which is exiting. Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> --- mm/oom_kill.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 27949ef..a3868fd 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -311,9 +311,6 @@ enum oom_scan_t oom_scan_process_thread(struct oom_control *oc, if (oom_task_origin(task)) return OOM_SCAN_SELECT; - if (task_will_free_mem(task) && !is_sysrq_oom(oc)) - return OOM_SCAN_ABORT; - return OOM_SCAN_OK; } -- 1.8.3.1 -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>