ksoftirqd: Enable IRQs and call cond_resched() before poking RCU

[firefly-linux-kernel-4.4.55.git] / kernel / fork.c

diff --git a/kernel/fork.c b/kernel/fork.c
index c271467da4f9602fbac045b1e718ab9f5c041522..514dbc40f98fcdd9adfac0f13f9a28e8ac55eacd 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1045,6 +1045,11 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
        sig->nr_threads = 1;
        atomic_set(&sig->live, 1);
        atomic_set(&sig->sigcnt, 1);
+
+       /* list_add(thread_node, thread_head) without INIT_LIST_HEAD() */
+       sig->thread_head = (struct list_head)LIST_HEAD_INIT(tsk->thread_node);
+       tsk->thread_node = (struct list_head)LIST_HEAD_INIT(sig->thread_head);
+
        init_waitqueue_head(&sig->wait_chldexit);
        sig->curr_target = tsk;
        init_sigpending(&sig->shared_pending);
@@ -1319,7 +1324,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
                goto bad_fork_cleanup_policy;
        retval = audit_alloc(p);
        if (retval)
-               goto bad_fork_cleanup_policy;
+               goto bad_fork_cleanup_perf;
        /* copy all the process information */
        retval = copy_semundo(clone_flags, p);
        if (retval)
@@ -1471,6 +1476,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
                        p->group_leader = current->group_leader;
                        list_add_tail_rcu(&p->thread_group,
                                          &p->group_leader->thread_group);
+                       list_add_tail_rcu(&p->thread_node,
+                                         &p->signal->thread_head);
                }
                attach_pid(p, PIDTYPE_PID, pid);
                nr_threads++;
@@ -1515,8 +1522,9 @@ bad_fork_cleanup_semundo:
        exit_sem(p);
 bad_fork_cleanup_audit:
        audit_free(p);
-bad_fork_cleanup_policy:
+bad_fork_cleanup_perf:
        perf_event_free_task(p);
+bad_fork_cleanup_policy:
 #ifdef CONFIG_NUMA
        mpol_put(p->mempolicy);
 bad_fork_cleanup_cgroup: