virtio: console: Don't call hvc_remove() on unplugging console ports

hvc_remove() has some bug which freezes other active hvc ports when one
port is removed.

So disable calling of hvc_remove() which deregisters a port with the
hvc_console.

If the hvc_console code calls into our get_chars() routine as a result
of a poll operation, we will return -EPIPE and the hvc_console code will
then do the necessary cleanup.

This call will be restored when the bug in hvc_remove() is found and
fixed.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

drivers/char/virtio_console.c

@@ -869,7 +869,18 @@ static int remove_port(struct port *port)
 		spin_lock_irq(&pdrvdata_lock);
 		list_del(&port->cons.list);
 		spin_unlock_irq(&pdrvdata_lock);
+#if 0
+		/*
+		 * hvc_remove() not called as removing one hvc port
+		 * results in other hvc ports getting frozen.
+		 *
+		 * Once this is resolved in hvc, this functionality
+		 * will be enabled.  Till that is done, the -EPIPE
+		 * return from get_chars() above will help
+		 * hvc_console.c to clean up on ports we remove here.
+		 */
 		hvc_remove(port->cons.hvc);
+#endif
 	}
 	if (port->guest_connected)
 		send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0);