diff options
Diffstat (limited to 'kernel/pid_namespace.c')
| -rw-r--r-- | kernel/pid_namespace.c | 33 |
1 files changed, 31 insertions, 2 deletions
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c index 57bc1fd35b3c..b3c7fd554250 100644 --- a/kernel/pid_namespace.c +++ b/kernel/pid_namespace.c @@ -149,7 +149,12 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns) { int nr; int rc; - struct task_struct *task; + struct task_struct *task, *me = current; + + /* Ignore SIGCHLD causing any terminated children to autoreap */ + spin_lock_irq(&me->sighand->siglock); + me->sighand->action[SIGCHLD - 1].sa.sa_handler = SIG_IGN; + spin_unlock_irq(&me->sighand->siglock); /* * The last thread in the cgroup-init thread group is terminating. @@ -179,11 +184,31 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns) } read_unlock(&tasklist_lock); + /* Firstly reap the EXIT_ZOMBIE children we may have. */ do { clear_thread_flag(TIF_SIGPENDING); rc = sys_wait4(-1, NULL, __WALL, NULL); } while (rc != -ECHILD); + /* + * sys_wait4() above can't reap the TASK_DEAD children. + * Make sure they all go away, see __unhash_process(). + */ + for (;;) { + bool need_wait = false; + + read_lock(&tasklist_lock); + if (!list_empty(¤t->children)) { + __set_current_state(TASK_UNINTERRUPTIBLE); + need_wait = true; + } + read_unlock(&tasklist_lock); + + if (!need_wait) + break; + schedule(); + } + if (pid_ns->reboot) current->signal->group_exit_code = pid_ns->reboot; @@ -191,6 +216,7 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns) return; } +#ifdef CONFIG_CHECKPOINT_RESTORE static int pid_ns_ctl_handler(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { @@ -218,8 +244,8 @@ static struct ctl_table pid_ns_ctl_table[] = { }, { } }; - static struct ctl_path kern_path[] = { { .procname = "kernel", }, { } }; +#endif /* CONFIG_CHECKPOINT_RESTORE */ int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd) { @@ -253,7 +279,10 @@ int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd) static __init int pid_namespaces_init(void) { pid_ns_cachep = KMEM_CACHE(pid_namespace, SLAB_PANIC); + +#ifdef CONFIG_CHECKPOINT_RESTORE register_sysctl_paths(kern_path, pid_ns_ctl_table); +#endif return 0; } |