diff --git a/backends/hostmem.c b/backends/hostmem.c
index 89feb9e..d8faab4 100644
--- a/backends/hostmem.c
+++ b/backends/hostmem.c
@@ -237,6 +237,15 @@
     backend->prealloc = mem_prealloc;
 }
 
+bool host_memory_backend_mr_inited(HostMemoryBackend *backend)
+{
+    /*
+     * NOTE: We forbid zero-length memory backend, so here zero means
+     * "we haven't inited the backend memory region yet".
+     */
+    return memory_region_size(&backend->mr) != 0;
+}
+
 MemoryRegion *
 host_memory_backend_get_memory(HostMemoryBackend *backend, Error **errp)
 {
diff --git a/include/sysemu/hostmem.h b/include/sysemu/hostmem.h
index ecae0cf..ed6a437 100644
--- a/include/sysemu/hostmem.h
+++ b/include/sysemu/hostmem.h
@@ -62,6 +62,7 @@
     MemoryRegion mr;
 };
 
+bool host_memory_backend_mr_inited(HostMemoryBackend *backend);
 MemoryRegion *host_memory_backend_get_memory(HostMemoryBackend *backend,
                                              Error **errp);