mm: list_lru: fix almost infinite loop causing effective livelock

[linux-beck.git] / mm / memory.c

diff --git a/mm/memory.c b/mm/memory.c
index f7b7692c05edee78faf951778bb3909143ac9ac1..1311f26497e6a0f776682ed8a7e23b8620a5b9ad 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3865,15 +3865,21 @@ int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
         * space.  Kernel faults are handled more gracefully.
         */
        if (flags & FAULT_FLAG_USER)
-               mem_cgroup_enable_oom();
+               mem_cgroup_oom_enable();
 
        ret = __handle_mm_fault(mm, vma, address, flags);
 
-       if (flags & FAULT_FLAG_USER)
-               mem_cgroup_disable_oom();
-
-       if (WARN_ON(task_in_memcg_oom(current) && !(ret & VM_FAULT_OOM)))
-               mem_cgroup_oom_synchronize();
+       if (flags & FAULT_FLAG_USER) {
+               mem_cgroup_oom_disable();
+                /*
+                 * The task may have entered a memcg OOM situation but
+                 * if the allocation error was handled gracefully (no
+                 * VM_FAULT_OOM), there is no need to kill anything.
+                 * Just clean up the OOM state peacefully.
+                 */
+                if (task_in_memcg_oom(current) && !(ret & VM_FAULT_OOM))
+                        mem_cgroup_oom_synchronize(false);
+       }
 
        return ret;
 }