1 files changed, 5 insertions, 0 deletions

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 68d87103b493..105f273b6f86 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2905,9 +2905,14 @@ static void cgroup_enable_task_cg_lists(void)
                  * 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.
+                 * Do it while holding siglock so that we don't end up
+                 * racing against cgroup_exit().
                  */
+                spin_lock_irq(&p->sighand->siglock);
                 if (!(p->flags & PF_EXITING) && list_empty(&p->cg_list))
                         list_add(&p->cg_list, &task_css_set(p)->tasks);
+                spin_unlock_irq(&p->sighand->siglock);
+
                 task_unlock(p);
         } while_each_thread(g, p);
         read_unlock(&tasklist_lock);