diff --git a/executer/include/uprotocol.h b/executer/include/uprotocol.h
index 9892a0ac..5bd5ddc0 100644
--- a/executer/include/uprotocol.h
+++ b/executer/include/uprotocol.h
@@ -191,6 +191,7 @@ struct syscall_response {
 	long ret;
 	unsigned long fault_address;
 	unsigned long fault_reason;
+	void *private_data;
 };
 
 struct syscall_ret_desc {
diff --git a/executer/kernel/mcctrl/syscall.c b/executer/kernel/mcctrl/syscall.c
index f06ec042..d4d62f1a 100644
--- a/executer/kernel/mcctrl/syscall.c
+++ b/executer/kernel/mcctrl/syscall.c
@@ -2065,6 +2065,17 @@ void __return_syscall(ihk_os_t os, struct ikc_scd_packet *packet,
 	/* Map response structure and notify offloading thread */
 	res->ret = ret;
 	res->stid = stid;
+	res->private_data = 0;
+
+	/* Special case for open() to return private_data */
+	if (packet->req.number == __NR_open && ret > 0) {
+		struct fd f;
+		f = fdget(ret);
+		if (f.file) {
+			res->private_data = f.file->private_data;
+			fdput(f);
+		}
+	}
 
 	if (__notify_syscall_requester(os, packet, res) < 0) {
 		printk("%s: WARNING: failed to notify PID %d\n",
diff --git a/kernel/include/syscall.h b/kernel/include/syscall.h
index c85f5038..eadf7e8d 100644
--- a/kernel/include/syscall.h
+++ b/kernel/include/syscall.h
@@ -294,6 +294,7 @@ struct syscall_response {
 	long ret;
 	unsigned long fault_address;
 	unsigned long fault_reason;
+	void *private_data;
 };
 
 struct syscall_post {
diff --git a/kernel/syscall.c b/kernel/syscall.c
index 11d76411..4142ae40 100644
--- a/kernel/syscall.c
+++ b/kernel/syscall.c
@@ -268,6 +268,7 @@ long do_syscall(struct syscall_request *req, int cpu, int pid)
 	req->rtid = cpu_local_var(current)->tid;
 	req->ttid = 0;
 	res.req_thread_status = IHK_SCD_REQ_THREAD_SPINNING;
+	res.private_data = NULL;
 #ifdef POSTK_DEBUG_TEMP_FIX_26 /* do_syscall arg pid is not targetpid */
 	send_syscall(req, cpu, target_pid, &res);
 #else /* POSTK_DEBUG_TEMP_FIX_26 */
@@ -477,6 +478,13 @@ long do_syscall(struct syscall_request *req, int cpu, int pid)
 	}
 #endif // PROFILE_ENABLE
 
+	if (req->number == __NR_open && rc > 0) {
+		if (res.private_data) {
+			kprintf("%s: open fd: %d, private_data: 0x%lx\n",
+				__FUNCTION__, rc, res.private_data);
+		}
+	}
+
 	monitor->status = mstatus;
 	monitor->counter++;
 	return rc;