diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c
index e3db6fbeadef..e8ae23e3c06c 100644
--- a/drivers/usb/class/cdc-wdm.c
+++ b/drivers/usb/class/cdc-wdm.c
@@ -151,7 +151,7 @@ static void wdm_out_callback(struct urb *urb)
 	kfree(desc->outbuf);
 	desc->outbuf = NULL;
 	clear_bit(WDM_IN_USE, &desc->flags);
-	wake_up(&desc->wait);
+	wake_up_all(&desc->wait);
 }
 
 static void wdm_in_callback(struct urb *urb)
@@ -426,6 +426,7 @@ static ssize_t wdm_write
 		clear_bit(WDM_IN_USE, &desc->flags);
 		dev_err(&desc->intf->dev, "Tx URB error: %d\n", rv);
 		rv = usb_translate_errors(rv);
+		wake_up_all(&desc->wait);
 		goto out_free_mem_pm;
 	} else {
 		dev_dbg(&desc->intf->dev, "Tx URB has been submitted index=%d\n",
@@ -587,15 +588,13 @@ static int wdm_flush(struct file *file, fl_owner_t id)
 {
 	struct wdm_device *desc = file->private_data;
 
-	wait_event(desc->wait,
-			/*
-			 * needs both flags. We cannot do with one
-			 * because resetting it would cause a race
-			 * with write() yet we need to signal
-			 * a disconnect
-			 */
-			!test_bit(WDM_IN_USE, &desc->flags) ||
-			test_bit(WDM_DISCONNECTING, &desc->flags));
+	pr_err("wdm_flush: file=%px flags=%lx\n", file, desc->flags);
+	while (wait_event_timeout(desc->wait, !test_bit(WDM_IN_USE, &desc->flags) ||
+				  test_bit(WDM_DISCONNECTING, &desc->flags), 30 * HZ) == 0) {
+		pr_err("INFO: task %s:%d blocked for more than 30 seconds.\n",
+		       current->comm, current->pid);
+		pr_err("wdm_flush: file=%px flags=%lx\n", file, desc->flags);
+	}
 
 	/* cannot dereference desc->intf if WDM_DISCONNECTING */
 	if (test_bit(WDM_DISCONNECTING, &desc->flags))