diff --git a/mm/oom_kill.c b/mm/oom_kill.c index a5493a3b4851..20f41b082e16 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -215,6 +215,18 @@ static struct task_struct *select_bad_process(unsigned long *ppoints) if (is_init(p)) continue; + /* + * This task already has access to memory reserves and is + * being killed. Don't allow any other task access to the + * memory reserve. + * + * Note: this may have a chance of deadlock if it gets + * blocked waiting for another task which itself is waiting + * for memory. Is there a better alternative? + */ + if (test_tsk_thread_flag(p, TIF_MEMDIE)) + return ERR_PTR(-1UL); + /* * This is in the process of releasing memory so wait for it * to finish before killing some other task by mistake. @@ -223,16 +235,15 @@ static struct task_struct *select_bad_process(unsigned long *ppoints) * go ahead if it is exiting: this will simply set TIF_MEMDIE, * which will allow it to gain access to memory reserves in * the process of exiting and releasing its resources. - * Otherwise we could get an OOM deadlock. + * Otherwise we could get an easy OOM deadlock. */ - if ((p->flags & PF_EXITING) && p == current) { + if (p->flags & PF_EXITING) { + if (p != current) + return ERR_PTR(-1UL); + chosen = p; *ppoints = ULONG_MAX; - break; } - if ((p->flags & PF_EXITING) || - test_tsk_thread_flag(p, TIF_MEMDIE)) - return ERR_PTR(-1UL); if (p->oomkilladj == OOM_DISABLE) continue;