[Qemu-devel] [PULL 04/23] memory: make memory_listener_unregister idempotent

[Michael S. Tsirkin]

From: Paolo Bonzini <address@hidden>

Make it easy to unregister a MemoryListener without tracking whether it
had been registered before.

Signed-off-by: Paolo Bonzini <address@hidden>
Reviewed-by: Philippe Mathieu-Daudé <address@hidden>
Reviewed-by: Michael S. Tsirkin <address@hidden>
Signed-off-by: Michael S. Tsirkin <address@hidden>
---
 memory.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/memory.c b/memory.c
index 6c58373..ed8b5aa 100644
--- a/memory.c
+++ b/memory.c
@@ -2371,8 +2371,13 @@ void memory_listener_register(MemoryListener *listener, 
AddressSpace *as)
 
 void memory_listener_unregister(MemoryListener *listener)
 {
+    if (!listener->address_space) {
+        return;
+    }
+
     QTAILQ_REMOVE(&memory_listeners, listener, link);
     QTAILQ_REMOVE(&listener->address_space->listeners, listener, link_as);
+    listener->address_space = NULL;
 }
 
 void address_space_init(AddressSpace *as, MemoryRegion *root, const char *name)
-- 
MST