diff --git a/include/condy/runtime.hpp b/include/condy/runtime.hpp
index aaf0de31..e2bc84d1 100644
--- a/include/condy/runtime.hpp
+++ b/include/condy/runtime.hpp
@@ -158,10 +158,6 @@ class Runtime {
                 flush_global_queue_();
                 ring_enabled_.store(true, std::memory_order_relaxed);
             }
-
-            if (!disable_register_ring_fd_) {
-                io_uring_register_ring_fd(ring_.ring());
-            }
         } else if (run_thread_id_ == std::this_thread::get_id()) {
             flush_ring_();
         } else {
@@ -169,6 +165,10 @@ class Runtime {
                 "Runtime::run() can only be called from the same thread");
         }
 
+        if (!disable_register_ring_fd_) {
+            io_uring_register_ring_fd(ring_.ring());
+        }
+
         while (true) {
             tick_count_++;
 
@@ -189,6 +189,10 @@ class Runtime {
             flush_ring_wait_();
         }
 
+        if (!disable_register_ring_fd_) {
+            io_uring_unregister_ring_fd(ring_.ring());
+        }
+
         tick_count_ = 0;
         exit_allowed_.store(false, std::memory_order_release);
     }
diff --git a/tests/test_runtime.cpp b/tests/test_runtime.cpp
index 8c61d55a..6aba0a09 100644
--- a/tests/test_runtime.cpp
+++ b/tests/test_runtime.cpp
@@ -1,3 +1,4 @@
+#include "condy/async_operations.hpp"
 #include "condy/coro.hpp"
 #include "condy/detail/async_operations.hpp"
 #include "condy/detail/invoker.hpp"
@@ -6,6 +7,7 @@
 #include "condy/task.hpp"
 #include <atomic>
 #include <doctest.h>
+#include <memory>
 #include <thread>
 
 namespace {
@@ -301,3 +303,24 @@ TEST_CASE("test runtime - cross-thread schedule between runs") {
 
     REQUIRE(invoker.finished);
 }
+
+TEST_CASE("test runtime - runtime destroyed on another runtime") {
+    condy::Runtime runtime_a(options);
+
+    auto func = [&]() -> condy::Coro<void> {
+        {
+            auto runtime_b = std::make_unique<condy::Runtime>(options);
+            std::thread thread_b([&]() {
+                runtime_b->allow_exit();
+                runtime_b->run();
+            });
+            thread_b.join();
+        }
+
+        co_await condy::async_nop();
+    };
+
+    condy::co_spawn(runtime_a, func()).detach();
+    runtime_a.allow_exit();
+    runtime_a.run();
+}