svn commit: r273219 - head/sys/dev/vt

[Ed Maste]

Author: emaste
Date: Fri Oct 17 13:55:45 2014
New Revision: 273219
URL: https://svnweb.freebsd.org/changeset/base/273219

Log:
  Do nothing in vt_upgrade if there is no vt driver
  
  Previously, if no drivers attached at boot we would panic with
  "vtbuf_fill_locked begin.tp_row 0 must be < screen height 0".
  
  PR:		192248
  Reviewed by:	ray
  MFC after:	3 days
  Sponsored by:	DARPA, AFRL
  Differential Revision: https://reviews.freebsd.org/D954

Modified:
  head/sys/dev/vt/vt_core.c

Modified: head/sys/dev/vt/vt_core.c
==============================================================================
--- head/sys/dev/vt/vt_core.c	Fri Oct 17 13:50:37 2014	(r273218)
+++ head/sys/dev/vt/vt_core.c	Fri Oct 17 13:55:45 2014	(r273219)
@@ -2498,6 +2498,8 @@ vt_upgrade(struct vt_device *vd)
 
 	if (!vty_enabled(VTY_VT))
 		return;
+	if (main_vd->vd_driver == NULL)
+		return;
 
 	for (i = 0; i < VT_MAXWINDOWS; i++) {
 		vw = vd->vd_windows[i];