935 sv_lyr_open() misses one NULL-pointer check
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Gordon Ross <gwr@nexenta.com>

*** 19,28 ****
--- 19,30 ----
   * CDDL HEADER END
   */
  /*
   * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
+  *
+  * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
   */
  
  /*
   * Storage Volume Character and Block Driver (SV)
   *
*** 1234,1243 ****
--- 1236,1246 ----
                          /*
                           * Re-acquire svp if the driver changed *devp.
                           */
  
                          if (*devp != odev) {
+                                 if (svp != NULL)
                                          rw_exit(&svp->sv_lock);
  
                                  svp = sv_dev_to_sv(*devp, NULL);
  
                                  if (svp) {