1 files changed, 30 insertions, 14 deletions

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index e905d5f53051..ce5f3fc25d6d 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -149,7 +149,8 @@ struct ports_device {
         spinlock_t ports_lock;
 
         /* To protect the vq operations for the control channel */
-        spinlock_t cvq_lock;
+        spinlock_t c_ivq_lock;
+        spinlock_t c_ovq_lock;
 
         /* The current config space is stored here */
         struct virtio_console_config config;
@@ -569,11 +570,14 @@ static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id,
         vq = portdev->c_ovq;
 
         sg_init_one(sg, &cpkt, sizeof(cpkt));
+
+        spin_lock(&portdev->c_ovq_lock);
         if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt, GFP_ATOMIC) == 0) {
                 virtqueue_kick(vq);
                 while (!virtqueue_get_buf(vq, &len))
                         cpu_relax();
         }
+        spin_unlock(&portdev->c_ovq_lock);
         return 0;
 }
 
@@ -1436,7 +1440,7 @@ static int add_port(struct ports_device *portdev, u32 id)
                  * rproc_serial does not want the console port, only
                  * the generic port implementation.
                  */
-                port->host_connected = port->guest_connected = true;
+                port->host_connected = true;
         else if (!use_multiport(port->portdev)) {
                 /*
                  * If we're not using multiport support,
@@ -1709,23 +1713,23 @@ static void control_work_handler(struct work_struct *work)
         portdev = container_of(work, struct ports_device, control_work);
         vq = portdev->c_ivq;
 
-        spin_lock(&portdev->cvq_lock);
+        spin_lock(&portdev->c_ivq_lock);
         while ((buf = virtqueue_get_buf(vq, &len))) {
-                spin_unlock(&portdev->cvq_lock);
+                spin_unlock(&portdev->c_ivq_lock);
 
                 buf->len = len;
                 buf->offset = 0;
 
                 handle_control_message(portdev, buf);
 
-                spin_lock(&portdev->cvq_lock);
+                spin_lock(&portdev->c_ivq_lock);
                 if (add_inbuf(portdev->c_ivq, buf) < 0) {
                         dev_warn(&portdev->vdev->dev,
                                  "Error adding buffer to queue\n");
                         free_buf(buf, false);
                 }
         }
-        spin_unlock(&portdev->cvq_lock);
+        spin_unlock(&portdev->c_ivq_lock);
 }
 
 static void out_intr(struct virtqueue *vq)
@@ -1752,13 +1756,23 @@ static void in_intr(struct virtqueue *vq)
         port->inbuf = get_inbuf(port);
 
         /*
-         * Don't queue up data when port is closed.  This condition
+         * Normally the port should not accept data when the port is
+         * closed. For generic serial ports, the host won't (shouldn't)
+         * send data till the guest is connected. But this condition
          * can be reached when a console port is not yet connected (no
-         * tty is spawned) and the host sends out data to console
-         * ports.  For generic serial ports, the host won't
-         * (shouldn't) send data till the guest is connected.
+         * tty is spawned) and the other side sends out data over the
+         * vring, or when a remote devices start sending data before
+         * the ports are opened.
+         *
+         * A generic serial port will discard data if not connected,
+         * while console ports and rproc-serial ports accepts data at
+         * any time. rproc-serial is initiated with guest_connected to
+         * false because port_fops_open expects this. Console ports are
+         * hooked up with an HVC console and is initialized with
+         * guest_connected to true.
          */
-        if (!port->guest_connected)
+
+        if (!port->guest_connected && !is_rproc_serial(port->portdev->vdev))
                 discard_port_data(port);
 
         spin_unlock_irqrestore(&port->inbuf_lock, flags);
@@ -1986,10 +2000,12 @@ static int virtcons_probe(struct virtio_device *vdev)
         if (multiport) {
                 unsigned int nr_added_bufs;
 
-                spin_lock_init(&portdev->cvq_lock);
+                spin_lock_init(&portdev->c_ivq_lock);
+                spin_lock_init(&portdev->c_ovq_lock);
                 INIT_WORK(&portdev->control_work, &control_work_handler);
 
-                nr_added_bufs = fill_queue(portdev->c_ivq, &portdev->cvq_lock);
+                nr_added_bufs = fill_queue(portdev->c_ivq,
+                                           &portdev->c_ivq_lock);
                 if (!nr_added_bufs) {
                         dev_err(&vdev->dev,
                                 "Error allocating buffers for control queue\n");
@@ -2140,7 +2156,7 @@ static int virtcons_restore(struct virtio_device *vdev)
                 return ret;
 
         if (use_multiport(portdev))
-                fill_queue(portdev->c_ivq, &portdev->cvq_lock);
+                fill_queue(portdev->c_ivq, &portdev->c_ivq_lock);
 
         list_for_each_entry(port, &portdev->ports, list) {
                 port->in_vq = portdev->in_vqs[port->id];