aboutsummaryrefslogtreecommitdiffstats
path: root/ipc/namespace.c
diff options
context:
space:
mode:
Diffstat (limited to 'ipc/namespace.c')
-rw-r--r--ipc/namespace.c11
1 files changed, 11 insertions, 0 deletions
diff --git a/ipc/namespace.c b/ipc/namespace.c
index fe3c97aa99d..f7a35be2e77 100644
--- a/ipc/namespace.c
+++ b/ipc/namespace.c
@@ -26,6 +26,8 @@ static struct ipc_namespace *clone_ipc_ns(struct ipc_namespace *old_ns)
msg_init_ns(ns);
shm_init_ns(ns);
+ register_ipcns_notifier(ns);
+
kref_init(&ns->kref);
return ns;
}
@@ -81,6 +83,15 @@ void free_ipc_ns(struct kref *kref)
struct ipc_namespace *ns;
ns = container_of(kref, struct ipc_namespace, kref);
+ /*
+ * Unregistering the hotplug notifier at the beginning guarantees
+ * that the ipc namespace won't be freed while we are inside the
+ * callback routine. Since the blocking_notifier_chain_XXX routines
+ * hold a rw lock on the notifier list, unregister_ipcns_notifier()
+ * won't take the rw lock before blocking_notifier_call_chain() has
+ * released the rd lock.
+ */
+ unregister_ipcns_notifier(ns);
sem_exit_ns(ns);
msg_exit_ns(ns);
shm_exit_ns(ns);