memory: unregister AddressSpace MemoryListener within BQL
address_space_destroy_dispatch is called from an RCU callback and hence
outside the iothread mutex (BQL). However, after address_space_destroy
no new accesses can hit the destroyed AddressSpace so it is not necessary
to observe changes to the memory map. Move the memory_listener_unregister
call earlier, to make it thread-safe again.
Reported-by: Alex Williamson <alex.williamson@redhat.com>
Fixes: 374f2981d1f10bc4307f250f24b2a7ddb9b14be0
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
diff --git a/exec.c b/exec.c
index 6b79ad1..6dff7bc 100644
--- a/exec.c
+++ b/exec.c
@@ -2059,11 +2059,15 @@
memory_listener_register(&as->dispatch_listener, as);
}
+void address_space_unregister(AddressSpace *as)
+{
+ memory_listener_unregister(&as->dispatch_listener);
+}
+
void address_space_destroy_dispatch(AddressSpace *as)
{
AddressSpaceDispatch *d = as->dispatch;
- memory_listener_unregister(&as->dispatch_listener);
g_free(d);
as->dispatch = NULL;
}
