f Also set/check processing flag for sync event processing

Author: tnull

lightning/src/ln/channelmanager.rs

@@ -5889,6 +5889,10 @@ where
 	/// An [`EventHandler`] may safely call back to the provider in order to handle an event.
 	/// However, it must not call [`Writeable::write`] as doing so would result in a deadlock.
 	fn process_pending_events<H: Deref>(&self, handler: H) where H::Target: EventHandler {
+		if self.pending_events_processor.compare_exchange(false, true, Ordering::Acquire, Ordering::Relaxed).is_err() {
+			return;
+		}
+
 		PersistenceNotifierGuard::optionally_notify(&self.total_consistency_lock, &self.persistence_notifier, || {
 			let mut result = NotifyOption::SkipPersist;
 
@@ -5909,6 +5913,8 @@ where
 
 			result
 		});
+
+		self.pending_events_processor.store(false, Ordering::Release);
 	}
 }