virtio: console: Return -EPIPE to hvc_console if we lost the connection

hvc_console handles -EPIPE properly when the connection to the host is
lost.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

1 files changed, 6 insertions, 2 deletions

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index f63bf77a4825..11a9573f901e 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -653,7 +653,7 @@ static int put_chars(u32 vtermno, const char *buf, int count)
 
         port = find_port_by_vtermno(vtermno);
         if (!port)
-                return 0;
+                return -EPIPE;
 
         return send_buf(port, (void *)buf, count);
 }
@@ -669,9 +669,13 @@ static int get_chars(u32 vtermno, char *buf, int count)
 {
         struct port *port;
 
+        /* If we've not set up the port yet, we have no input to give. */
+        if (unlikely(early_put_chars))
+                return 0;
+
         port = find_port_by_vtermno(vtermno);
         if (!port)
-                return 0;
+                return -EPIPE;
 
         /* If we don't have an input queue yet, we can't get input. */
         BUG_ON(!port->in_vq);