diff --git a/tests/sys/fs/fusefs/mockfs.hh b/tests/sys/fs/fusefs/mockfs.hh
--- a/tests/sys/fs/fusefs/mockfs.hh
+++ b/tests/sys/fs/fusefs/mockfs.hh
@@ -388,6 +388,9 @@
 	/* Process FUSE requests endlessly */
 	void loop();
 
+	/* Begin processing requests from the kernel */
+	void start_service();
+
 	/*
 	 * Send an asynchronous notification to invalidate a directory entry.
 	 * Similar to libfuse's fuse_lowlevel_notify_inval_entry
diff --git a/tests/sys/fs/fusefs/mockfs.cc b/tests/sys/fs/fusefs/mockfs.cc
--- a/tests/sys/fs/fusefs/mockfs.cc
+++ b/tests/sys/fs/fusefs/mockfs.cc
@@ -550,9 +550,8 @@
 	if (0 != sigaction(SIGUSR1, &sa, NULL))
 		throw(std::system_error(errno, std::system_category(),
 			"Couldn't handle SIGUSR1"));
-	if (pthread_create(&m_daemon_id, NULL, service, (void*)this))
-		throw(std::system_error(errno, std::system_category(),
-			"Couldn't Couldn't start fuse thread"));
+	if (!no_auto_init)
+		start_service();
 }
 
 MockFS::~MockFS() {
@@ -1018,6 +1017,12 @@
 	ASSERT_TRUE(res == static_cast<ssize_t>(in.header.len) || m_quit);
 }
 
+void MockFS::start_service() {
+	if (pthread_create(&m_daemon_id, NULL, service, (void*)this))
+		throw(std::system_error(errno, std::system_category(),
+			"Couldn't Couldn't start fuse thread"));
+}
+
 void MockFS::write_response(const mockfs_buf_out &out) {
 	fd_set writefds;
 	pollfd fds[1];
diff --git a/tests/sys/fs/fusefs/pre-init.cc b/tests/sys/fs/fusefs/pre-init.cc
--- a/tests/sys/fs/fusefs/pre-init.cc
+++ b/tests/sys/fs/fusefs/pre-init.cc
@@ -102,6 +102,8 @@
 	})));
 	expect_destroy(0);
 
+	m_mock->start_service();
+
 	ASSERT_EQ(0, pthread_create(&th1, NULL, unmount1, NULL));
 	nap();	/* Wait for th1 to block in unmount() */
 	sem_post(&sem0);
@@ -147,6 +149,8 @@
 		sem_wait(&sem0);
 	})));
 
+	m_mock->start_service();
+
 	if ((child = ::fork()) == 0) {
 		/*
 		 * In child.  This will block waiting for FUSE_INIT to complete
@@ -219,6 +223,8 @@
 		out.body.attr.attr_valid = UINT64_MAX;
 	})));
 
+	m_mock->start_service();
+
 	EXPECT_EQ(0, stat("mountpoint", &sb));
 	EXPECT_EQ(nlink, sb.st_nlink);
 }