dm crypt: add documentation

[karo-tx-linux.git] / kernel / cgroup.c

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 2727f92383596e4a6f7bec5072b1e804a7801916..6d8de051382b0687ab1a449c245ebb2f05cd38f0 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1722,7 +1722,12 @@ void cgroup_enable_task_cg_lists(void)
        use_task_css_set_links = 1;
        do_each_thread(g, p) {
                task_lock(p);
-               if (list_empty(&p->cg_list))
+               /*
+                * We should check if the process is exiting, otherwise
+                * it will race with cgroup_exit() in that the list
+                * entry won't be deleted though the process has exited.
+                */
+               if (!(p->flags & PF_EXITING) && list_empty(&p->cg_list))
                        list_add(&p->cg_list, &p->cgroups->tasks);
                task_unlock(p);
        } while_each_thread(g, p);