diff --git a/fs_mgr/libsnapshot/include/libsnapshot/snapuserd_client.h b/fs_mgr/libsnapshot/include/libsnapshot/snapuserd_client.h
index 2f671c2..aa9ba6e 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapuserd_client.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapuserd_client.h
@@ -70,6 +70,11 @@
     // Wait for snapuserd to disassociate with a dm-user control device. This
     // must ONLY be called if the control device has already been deleted.
     bool WaitForDeviceDelete(const std::string& control_device);
+
+    // Detach snapuserd. This shuts down the listener socket, and will cause
+    // snapuserd to gracefully exit once all handler threads have terminated.
+    // This should only be used on first-stage instances of snapuserd.
+    bool DetachSnapuserd();
 };
 
 }  // namespace snapshot
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/snapuserd_server.h b/fs_mgr/libsnapshot/include/libsnapshot/snapuserd_server.h
index cadfd71..1491aac 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapuserd_server.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapuserd_server.h
@@ -41,6 +41,7 @@
     QUERY,
     STOP,
     DELETE,
+    DETACH,
     INVALID,
 };
 
@@ -106,6 +107,7 @@
     bool IsTerminating() { return terminating_; }
 
     void RunThread(std::shared_ptr<DmUserHandler> handler);
+    void JoinAllThreads();
 
     // Find a DmUserHandler within a lock.
     HandlerList::iterator FindHandler(std::lock_guard<std::mutex>* proof_of_lock,
diff --git a/fs_mgr/libsnapshot/snapuserd_client.cpp b/fs_mgr/libsnapshot/snapuserd_client.cpp
index 9ee13db..7282bff 100644
--- a/fs_mgr/libsnapshot/snapuserd_client.cpp
+++ b/fs_mgr/libsnapshot/snapuserd_client.cpp
@@ -210,5 +210,13 @@
     return num_sectors;
 }
 
+bool SnapuserdClient::DetachSnapuserd() {
+    if (!Sendmsg("detach")) {
+        LOG(ERROR) << "Failed to detach snapuserd.";
+        return false;
+    }
+    return true;
+}
+
 }  // namespace snapshot
 }  // namespace android
diff --git a/fs_mgr/libsnapshot/snapuserd_server.cpp b/fs_mgr/libsnapshot/snapuserd_server.cpp
index 9d57ab0..7a5cead 100644
--- a/fs_mgr/libsnapshot/snapuserd_server.cpp
+++ b/fs_mgr/libsnapshot/snapuserd_server.cpp
@@ -38,6 +38,7 @@
     if (input == "stop") return DaemonOperations::STOP;
     if (input == "query") return DaemonOperations::QUERY;
     if (input == "delete") return DaemonOperations::DELETE;
+    if (input == "detach") return DaemonOperations::DETACH;
 
     return DaemonOperations::INVALID;
 }
@@ -72,19 +73,7 @@
 
 void SnapuserdServer::ShutdownThreads() {
     StopThreads();
-
-    // Acquire the thread list within the lock.
-    std::vector<std::shared_ptr<DmUserHandler>> dm_users;
-    {
-        std::lock_guard<std::mutex> guard(lock_);
-        dm_users = std::move(dm_users_);
-    }
-
-    for (auto& client : dm_users) {
-        auto& th = client->thread();
-
-        if (th.joinable()) th.join();
-    }
+    JoinAllThreads();
 }
 
 const std::string& DmUserHandler::GetMiscName() const {
@@ -214,6 +203,10 @@
             }
             return Sendmsg(fd, "success");
         }
+        case DaemonOperations::DETACH: {
+            terminating_ = true;
+            return Sendmsg(fd, "success");
+        }
         default: {
             LOG(ERROR) << "Received unknown message type from client";
             Sendmsg(fd, "fail");
@@ -234,7 +227,7 @@
 
     LOG(INFO) << "Exiting thread for handler: " << handler->GetMiscName();
 
-    // If the main thread called /emoveHandler, the handler was already removed
+    // If the main thread called RemoveHandler, the handler was already removed
     // from within the lock, and calling RemoveHandler again has no effect.
     RemoveHandler(handler->GetMiscName(), false);
 }
@@ -286,9 +279,26 @@
             }
         }
     }
+
+    JoinAllThreads();
     return true;
 }
 
+void SnapuserdServer::JoinAllThreads() {
+    // Acquire the thread list within the lock.
+    std::vector<std::shared_ptr<DmUserHandler>> dm_users;
+    {
+        std::lock_guard<std::mutex> guard(lock_);
+        dm_users = std::move(dm_users_);
+    }
+
+    for (auto& client : dm_users) {
+        auto& th = client->thread();
+
+        if (th.joinable()) th.join();
+    }
+}
+
 void SnapuserdServer::AddWatchedFd(android::base::borrowed_fd fd) {
     struct pollfd p = {};
     p.fd = fd.get();