4047 panic from dbuf_free_range() from dmu_free_object() while doing zfs receive
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>

@@ -18,11 +18,11 @@
  *
  * CDDL HEADER END
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2012 by Delphix. All rights reserved.
+ * Copyright (c) 2013 by Delphix. All rights reserved.
  */
 
 #ifndef _SYS_DNODE_H
 #define _SYS_DNODE_H
 

@@ -186,10 +186,12 @@
         uint16_t dn_next_bonuslen[TXG_SIZE];
         uint32_t dn_next_blksz[TXG_SIZE];       /* next block size in bytes */
 
         /* protected by dn_dbufs_mtx; declared here to fill 32-bit hole */
         uint32_t dn_dbufs_count;        /* count of dn_dbufs */
+        /* There are no level-0 blocks of this blkid or higher in dn_dbufs */
+        uint64_t dn_unlisted_l0_blkid;
 
         /* protected by os_lock: */
         list_node_t dn_dirty_link[TXG_SIZE];    /* next on dataset's dirty */
 
         /* protected by dn_mtx: */