ipcpd: Fix shutdown of link-state routing

The link_state component tried to unregister from the notifier while
it had threads running.

The deadlock happens when notifier_event had a rdlock trying to delete
a neighbour, while notifier_unreg tries to take the write lock. And
the delete can't complete in the notifier.

https://tree.taiga.io/project/dstaesse-ouroboros/us/113

We need to make sure that all threads are stopped before unregistering
from the notifier.

Updated link_state to use the start/stop() paradigm and not
create/cancel threads within init/fini().

Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>

1 files changed, 10 insertions, 0 deletions

diff --git a/src/ipcpd/unicast/routing.c b/src/ipcpd/unicast/routing.c
index f5417c24..4efc3ea6 100644
--- a/src/ipcpd/unicast/routing.c
+++ b/src/ipcpd/unicast/routing.c
@@ -57,6 +57,11 @@ int routing_init(enum pol_routing pr)
         return pff_type;
 }
 
+int routing_start(void)
+{
+        return r_ops->start();
+}
+
 struct routing_i * routing_i_create(struct pff * pff)
 {
         return r_ops->routing_i_create(pff);
@@ -67,6 +72,11 @@ void routing_i_destroy(struct routing_i * instance)
         return r_ops->routing_i_destroy(instance);
 }
 
+void routing_stop(void)
+{
+        r_ops->stop();
+}
+
 void routing_fini(void)
 {
         r_ops->fini();