virtio: console: Don't call hvc_remove() on unplugging console ports
authorAmit Shah <amit.shah@redhat.com>
Thu, 20 May 2010 04:15:47 +0000 (22:15 -0600)
committerRusty Russell <rusty@rustcorp.com.au>
Wed, 19 May 2010 12:45:48 +0000 (22:15 +0930)
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

index 11a9573..9a69870 100644 (file)
@@ -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);